CN103078635A - Embedded oscillation circuit - Google Patents
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- CN103078635A CN103078635A CN2012105926144A CN201210592614A CN103078635A CN 103078635 A CN103078635 A CN 103078635A CN 2012105926144 A CN2012105926144 A CN 2012105926144A CN 201210592614 A CN201210592614 A CN 201210592614A CN 103078635 A CN103078635 A CN 103078635A
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Abstract
The invention provides an embedded oscillation circuit. According to the embedded oscillation circuit, a negative feedback closed-loop form is adopted, the embedded oscillation circuit can be fully integrated in a chip by adopting a frequency-current conversion way, and a crystal oscillator which is required to be arranged additionally outside is eliminated, so that the process cost is saved; and moreover, an oscillation frequency generated by an annular oscillator is converted into direct current and is compared with current generated by a basic current generating circuit, a comparison result is fed back to the control end of the annular oscillator, and the frequency of the annular oscillator is changed, so that the deviation of a frequency signal is compensated, a working frequency with low temperature drift is output stably through a loop, and a high-accuracy frequency signal is generated.
Description
Technical field
The present invention relates to oscillating circuit equipment, relate in particular to a kind of built-in oscillating circuit.
Background technology
Making rapid progress of science and technology so that the developing trend low-power consumption of various device, area is little and low-cost, accurately clock generating circuit also trend towards on the full sheet integrated, high accuracy, high-frequency future development.Pierce circuit is generally used for providing clock signal to various integrated circuit (IC) chip.It is following several generally to provide the pierce circuit of clock signal to have for various circuit chips:
A kind of generation circuit that is based on ring oscillator.Ring oscillator generation circuit uses comparatively extensive, but in CMOS technique, owing to have the unsteadiness of temperature, technique and supply voltage, so that the output frequency stability of described Embedded clock circuit is relatively poor.
Another is lax (Relaxation) oscillator of RC, because its frequency accuracy is higher, present development is comparatively rapid, but because the operating frequency of RC relaxation oscillator is lower, the clock signal that therefore is not suitable for upper frequency is used.
Another kind also is that comparatively commonly clock signal is to adopt quartz crystal (Crystal) oscillator electricity as clock reference.
At present for consumer electronics product, such as 27/49M, the radio-frequency (RF) emission system of 315/433M frequency range, as the general employing of the pierce circuit that produces clock reference all is the third structure, Fig. 1 is the structural representation of clock signal generating circuit in the prior art, as shown in Figure 1, crystal oscillator produces signal by oscillator, and locks to obtain clock signal by PLL/DLL.Need to obtain suitable clock signal with phase-locked loop (PLL) or delay locked loop (DLL) at chip internal (being on the sheet).This pierce circuit can be realized very high precision (1~100ppm), but this scheme needs the extra external crystal-controlled oscillation that increases, not only greatly improved the cost of product, and need to take larger chip area and power consumption, and reduced the competitiveness of whole chip, therefore impact at some to the application in the consumer product of cost compare sensitivity, such as toy remote control product, controlled in wireless product and infrared remote control product etc.
Summary of the invention
The objective of the invention is to solve the deficiencies in the prior art, a kind of novel built-in oscillating circuit be provided, solve because the frequency shift (FS) that the variation of technique, supply voltage and temperature produces, and with low cost, frequency range larger built-in oscillating circuit.
For addressing the above problem, the invention provides a kind of built-in oscillating circuit, comprise that basic current produces circuit, ring oscillator, frequency-electric current conversion circuit and current comparator;
Described basic current produces circuit and comprises the first operational amplifier, the first amplifier tube, trimming resistors and mirror image circuit, described the first operational amplifier receives an input voltage, export an intermediate current by the first amplifier tube after described trimming resistors trims, described intermediate current is exported an output current through described mirror image circuit;
Described ring oscillator produces frequency signal;
Described frequency-electric current conversion circuit comprises the second operational amplifier, the second amplifier tube, some switches, charges and discharge electric capacity and electric current output module, described the second operational amplifier receives described input voltage and exports the first end of described the second amplifier tube to, described two switches are controlled respectively the described electric capacity that charges and discharge and are discharged and recharged the formation equivalent resistance module between the second end of described the second amplifier tube and ground, the 3rd end of described the second amplifier tube via described electric current output module after the described feedback current of output;
Output control voltage behind the more described feedback current of described current comparator and the described output current, described control voltage carries out feedback correction to the frequency signal that described ring oscillator produces, until the stable output of described frequency signal.
Further, during the stable output of the frequency signal of described ring oscillator, the value of described frequency signal is relevant with the capacitance that charges and discharge electric capacity with the resistance value that trims resistance.
Further, the output frequency of described built-in oscillator is:
Wherein, fout is the output frequency of described ring oscillator, and Cc is the described capacitance that charges and discharge electric capacity, (Rp+Rn) is the resistance value of described trimming resistors, and K is proportionality coefficient.
Further, produce in the circuit at described basic current, two inputs of described the first operational amplifier connect respectively the first link of described reference voltage and the first amplifier tube, the control end of described the first amplifier tube of output termination; The first link of described trimming resistors one end ground connection, described the first amplifier tube of another termination, the second link, the output of described first amplifier tube of input termination of described mirror image circuit are exported described reference current.
Further, described mirror image circuit comprises first mirror as efferent duct, described first mirror as the control end of described first amplifier tube of control termination of efferent duct, described first mirror as the first link of efferent duct export described reference current, described first mirror connects the described supply voltage of termination as second of efferent duct.
Further, described mirror image circuit comprises that first mirror is as input pipe, the second mirror image input pipe, first mirror is as efferent duct and the second mirror image efferent duct, described first mirror is as the second link of described first amplifier tube of control termination of input pipe, described first mirror connects the second link of described the second mirror image input pipe of termination as first of input pipe, described first mirror connects termination one supply voltage as second of input pipe, second of described the second mirror image input pipe connects the second link of described the first amplifier tube of termination, described first mirror is as the described first mirror of control termination of the efferent duct control end as input, described first mirror connects the second link of described the second mirror image efferent duct of termination as first of efferent duct, described first mirror connects the described supply voltage of termination as second of efferent duct, the control end of the described second mirror image input pipe of control termination of described the second mirror image efferent duct, the first link of described the second mirror image efferent duct is exported described reference current, the second link of described the second mirror image efferent duct is connected with first link of a first mirror as efferent duct.
Further, described mirror image circuit is the overriding mirror image circuit of multichannel, described trimming resistors is realized the adjusting of low level frequency departure to described reference current, and the overriding mirror image circuit of described multichannel realizes that high-order low bit frequency is selected and described reference current is realized high-order frequency departure adjusting.
Further, described overriding mirror image circuit is the common-source common-gate current mirror structure.
Further, the overriding mirror image circuit of described multichannel comprises that first mirror is as input pipe, the second mirror image input pipe, a plurality of first mirrors are as efferent duct and a plurality of the second mirror image efferent duct, described first mirror is as the second link of described first amplifier tube of control termination of input pipe, described first mirror connects the second link of described the second mirror image input pipe of termination as first of input pipe, described first mirror connects termination one supply voltage as second of input pipe, second of described the second mirror image input pipe connects the second link of described the first amplifier tube of termination, each described first mirror all connects described first mirror as the control end of input pipe as the control end of efferent duct, each described first mirror connects the described supply voltage of termination as second of efferent duct, the control end of each described the second mirror image efferent duct all connects the control end of described the second mirror image input pipe, the described reference current of rear output that links to each other of described the second mirror image efferent duct, the second link of each described the second mirror image efferent duct is connected with first link of a first mirror as efferent duct.
Further, described basic current produces circuit and receives a multidigit control signal, described multidigit control signal comprises frequency selection position, mirror image circuit adjusting position and resistance adjustment position, described frequency selects control some first mirrors in position to select to realize frequency range as the ratio value of input pipe as efferent duct and described first mirror, described mirror image circuit regulate all the other first mirrors of position control as efferent duct and described first mirror as the ratio value of input pipe to realize coarse adjustment in the frequency range, the resistance value of described trimming resistors is controlled with accurate adjustment in the realization frequency range in described resistance adjustment position.
Further, described frequency-electric current conversion circuit also comprises filter capacitor, the described high-frequency noise that charges and discharge the electric capacity generation of described filter capacitor filtering, described switch comprises first switch and second switch, the electric current output module comprises the first efferent duct and the second efferent duct, two inputs of described the second operational amplifier connect respectively the first link of described input voltage and described the second amplifier tube, an and end of filter capacitor and first switch, the control end of output termination second amplifier tube of described the second operational amplifier, the described end that charges and discharge electric capacity and second switch of another termination of described first switch, described second switch, filter capacitor and the equal ground connection of the other end that charges and discharge electric capacity, second of described the second amplifier tube connects the first link of termination the second efferent duct and the control end of the first efferent duct, the second link of described the second efferent duct links to each other with the first link of the first efferent duct, second of the first efferent duct connects termination one supply voltage, the control end of described the first efferent duct is exported described feedback current, and described first switch and second switch are respectively by two-phase non-overlapping clock signal controlling.
Further, described current comparator comprises the first mirror image tube, the second mirror image pipe, limit electric capacity and a mirror image module, the described feedback current of control termination of described first mirror image tube and the control end of described the first efferent duct, first of described first mirror image tube connects the second link of described the second mirror image pipe of termination, second of described first mirror image tube connects termination one supply voltage, the control end of described second efferent duct of control termination of described the second mirror image pipe, first of described the second mirror image pipe connects termination one output node, the described output node of first mirror picture input termination of described mirror image module, the described output current of the second mirror image input termination of described mirror image module, described output node is exported described feedback voltage.
Further, described frequency-electric current conversion circuit also comprises filter capacitor, the described high-frequency noise that charges and discharge the electric capacity generation of described filter capacitor filtering, described switch comprises first switch and second switch, the electric current output module comprises the first efferent duct, two inputs of described the second operational amplifier connect respectively the first link of described input voltage and described the second amplifier tube, an and end of filter capacitor and first switch, the control end of output termination second amplifier tube of described the second operational amplifier, the described end that charges and discharge electric capacity and second switch of another termination of described first switch, described second switch, filter capacitor and the equal ground connection of the other end that charges and discharge electric capacity, second of described the second amplifier tube connects the first link and the control end of termination the first efferent duct, second of the first efferent duct connects termination one supply voltage, the control end of described the first efferent duct is exported described feedback current, and described first switch and second switch are respectively by two-phase non-overlapping clock signal controlling.
Further, described current comparator comprises first mirror image tube, limit electric capacity and a mirror image module, the described feedback current of control termination of described first mirror image tube be connected the control end, first of the first efferent duct and connect termination one output node, second and connect termination one supply voltage, the described output node of one termination of described electric capacity, another termination supply voltage, the first mirror picture input termination output node of described mirror image module, the described output current of the second mirror image input termination, described output node is exported described feedback voltage.
Further, described built-in oscillating circuit also comprises many times of frequency dividers, described many times of frequency dividers are arranged between described ring oscillator and the described frequency-electric current conversion circuit, after described many times of frequency dividers carry out frequency division to described frequency signal, export described frequency-electric current conversion circuit to, so that described frequency-voltage conversion circuit steady operation receives described frequency signal.
Built-in oscillating circuit as claimed in claim 15 is characterized in that, when the stable output of described frequency signal, described frequency signal is:
Wherein, M is the frequency division multiple of described asynchronous frequency divider, and fout is the output frequency of described built-in oscillator, and Cc first charges and discharge the capacitance of electric capacity, (Rp+Rn) produces the resistance value of the trimming resistors of circuit for basic current, and K is proportionality coefficient.
Further, described many times of frequency dividers comprise the twice frequency divider of a plurality of cascades.
Further, described built-in oscillating circuit comprises that also one stablizes electric capacity, and described stable electric capacity one end is connected between described electric current comparison amplifier and the ring oscillator another termination supply voltage.
Further, described built-in oscillating circuit is arranged at frequency range at the toy remote control equipment of 27MHZ~49MHZ.
Further, the wireless control apparatus of frequency range 315MHz or 433MHZ.
Further, frequency range is in the infrared remote control equipment of 38KHz.
In sum, built-in oscillating circuit of the present invention adopts negative feedback closed loop road form, utilize frequency-electric current transform mode, make the built-in oscillating circuit can be all integrated in chip, having omitted needs the outside extra crystal oscillator that arranges, saved process costs, and be converted into direct current by the frequency of oscillation that ring oscillator is produced, and produce the electric current that circuit produces with described basic current and compare, then comparative result is fed back to the control end of ring oscillator, change the frequency of ring oscillator, thereby compensate by the deviation to frequency signal, thereby make the operating frequency of loop stability output Low Drift Temperature, produce high-precision frequency signal.
Further, in the described built-in oscillating circuit, described basic current produces circuit and selects by the low level fine tuning of six trimming resistors and high position control and the high-order low bit frequency of the overriding current mirror of multichannel, thereby can be by trimming a modification method to the process deviation of frequency signal, reach 0.1% frequency and trim precision, and can cover the whole scope that trims, not disconnected joint.
Described built-in oscillating circuit has higher stability not only in technique in the situation of temperature deviation and supply voltage deviation, export a stable clock signal, and its frequency signal scope is wide.
Description of drawings
Fig. 1 is the structural representation that crystal oscillator produces circuit in the prior art.
Fig. 2 .1~2.2 are the schematic diagram of built-in oscillating circuit among the several embodiment of the present invention.
Fig. 3 .1~3.3 produce the schematic diagram of circuit for basic current in the built-in oscillating circuit among the several embodiment of the present invention.
Fig. 4 .1~4.2 are the schematic diagram of built-in oscillating circuit medium frequency-electric current conversion circuit and electric current comparison amplifier in one embodiment of the invention.
Fig. 5 is the schematic diagram of ring oscillator in the built-in oscillating circuit in one embodiment of the invention.
Fig. 6 is the schematic diagram of many times of frequency dividers in the built-in oscillating circuit in one embodiment of the invention.
Embodiment
For making content of the present invention more clear understandable, below in conjunction with Figure of description, content of the present invention is described further.Certainly the present invention is not limited to this specific embodiment, and the known general replacement of those skilled in the art also is encompassed in protection scope of the present invention.
Secondly, the present invention utilizes schematic diagram to carry out detailed statement, and when example of the present invention was described in detail in detail, for convenience of explanation, schematic diagram did not amplify according to general ratio is local, should be with this as limitation of the invention.
Fig. 2 .1 is the schematic diagram of built-in oscillating circuit in one embodiment of the invention.Shown in Fig. 2 .1, built-in oscillating circuit of the present invention utilizes closed-loop structure, realizes stable output frequency by FEEDBACK CONTROL.Described built-in oscillating circuit comprises that basic current produces circuit 11 and ring oscillator 13, frequency-electric current conversion circuit 15 and differential amplifier circuit 12.Wherein ring oscillator 13, frequency-voltage conversion circuit 15 and current comparator 12 consist of a negative feedback cor-rection loop.
For the frequency signal of stabilized oscillator, reduce cost, the present invention adopts the closed loop circuit structure, and is integrated on the full sheet, and these deviations of frequency signal are compensated, and produces high-precision frequency signal.In the course of work of built-in oscillating circuit, the frequency signal of ring oscillator 13 be subject to temperature, the impact of the environment such as process deviation and supply voltage, for example when variations in temperature, when assumed temperature rises, control voltage Vctr moment does not change, then the frequency signal of ring oscillator 13 descends, so the output current Iout of frequency-electric current conversion circuit 15 begins to reduce, and output current Ib remains unchanged, so the control voltage Vctr of electric current comparison amplifier 12 reduces, then the frequency signal fout of ring oscillator 13 increases with the minimizing of control voltage Vctr, the output current Iout of frequency-electric current conversion circuit 15 is with increase, then negative feedback is regulated and is carried out always, until output current Iout and basic current Ib are equal, till namely the loop of built-in oscillating circuit is stablized again; Equally, when drop in temperature, identical negative feedback adjustment process occurs also, until the loop of built-in oscillating circuit again stable till.
Fig. 2 .2 is the schematic diagram of built-in oscillating circuit in another embodiment of the present invention, shown in Fig. 2 .2, described built-in oscillating circuit can also comprise voltage stabilizing generator 16 and many times of frequency dividers 14, described voltage stabilizing generator 16 receives an external power source VDD, and VDD is converted into VDDA and the input voltage Vb of stable output, described supply voltage VDDA produces circuit 11 for basic current in the described built-in oscillating circuit and the negative feedback cor-rection loop provides stable supply voltage, thereby guarantees the steady operation of built-in oscillating circuit.Described many times of frequency dividers 14 are arranged between described ring oscillator 13 and the frequency-electric current conversion circuit 15, after 13 couples of described frequency signal fout of described many times of frequency dividers carry out frequency division formation fractional frequency signal fb, export described frequency-electric current conversion circuit 15 to, so that described frequency-voltage conversion circuit steady operation receives described frequency signal, increase and described many times of frequency dividers 14 to be set to make described frequency-voltage conversion circuit 15 can steady operation.
In addition, described built-in oscillating circuit also comprises capacitor C 0, between one termination power voltage VDDA of capacitor C 0, the described current comparator 12 of another termination and the described ring oscillator 13, the Main Function of described capacitor C 0 is to produce a limit, to stablize the loop of whole built-in oscillating circuit, wherein, the described supply voltage VDDA of a termination of described capacitor C 0 can further reduce the phase noise of built-in oscillating circuit.
Fig. 3 .1 be in one embodiment of the invention in the built-in oscillating circuit basic current produce the schematic diagram of circuit.In preferred embodiment, the overriding mirror image circuit of multichannel can adopt the common-source common-gate current mirror structure, thereby has further reduced the temperature coefficient of image current, so that the output of reference current Iref is proportional to electric current I 1, and temperature independent.
Shown in Fig. 3 .1, described mirror image circuit is the overriding mirror image circuit of multichannel, described basic current produces circuit 11 and comprises the first operational amplifier A 1, the first amplifier tube M1 (the first amplifier tube is the NMOS pipe), trimming resistors (Rp+Rn) and mirror image circuit, the input of described the first operational amplifier A 1 connects respectively the first link of input voltage Vref and the first amplifier tube M1, the control end of the described first amplifier tube M1 of output termination of described the first operational amplifier A 1, the first link of described trimming resistors (Rp+Rn) two ends difference ground connection and described the first amplifier tube M1, second of described the first amplifier tube M1 connects the described burning voltage VDDA of termination, described mirror image circuit comprises first mirror as efferent duct, and described first mirror is as the control end of the described first amplifier tube M1 of control termination of efferent duct.Wherein said the first operational amplifier A 1 receives an input voltage Vb, exports an intermediate current I1 by the first amplifier tube A1 after described trimming resistors (Rp+Rn) trims, and described intermediate current I1 is through described mirror image circuit output reference current Iref.
Fig. 3 .2 be in another embodiment of the present invention in the built-in oscillating circuit basic current produce the schematic diagram of circuit.Shown in Fig. 3 .2, described basic current produces circuit 11 and comprises the first operational amplifier A 1, the first amplifier tube M1, trimming resistors (Rp+Rn) and mirror image circuit, mirror image circuit comprises that first mirror is as input pipe M3 in an embodiment, the second mirror image input pipe M2, first mirror is as efferent duct Mn1 and the second mirror image efferent duct Mp1, described first mirror is as the second link of described the first amplifier tube M1 of the control termination of input pipe M3, described first mirror connects the second link of described the second mirror image input pipe M2 of termination as first of input pipe M3, described first mirror connects termination one supply voltage VDDA as second of input pipe M3, second of described the second mirror image input pipe M2 connects the second link of described the first amplifier tube M1 of termination, described first mirror is as the described first mirror of control termination of the efferent duct Mn1 control end as input M3, described first mirror connects the second link of described the second mirror image efferent duct Mp1 of termination as first of efferent duct Mn1, described first mirror connects the described supply voltage VDDA of termination as second of efferent duct Mn1, the control end of described the second mirror image input pipe M2 of the control termination of described the second mirror image efferent duct Mp1, the first link of described the second mirror image efferent duct Mp1 is exported described reference current Ib, and the second link of described the second mirror image efferent duct Mp1 is connected with first link of a first mirror as efferent duct Mn1.
Fig. 3 .3 be in another embodiment of the present invention in the built-in oscillating circuit basic current produce the schematic diagram of circuit.Shown in Fig. 3 .3, in preferred embodiment, described mirror image circuit is the overriding mirror image circuit of multichannel, described basic current produces circuit 11 and comprises the first operational amplifier A 1, the first amplifier tube M1 (the first amplifier tube is the NMOS pipe), trimming resistors (Rp+Rn) and mirror image circuit, mirror image circuit adopts the overriding mirror image circuit of multichannel in an embodiment, comprise that first mirror is as input pipe M3, the second mirror image input pipe M2, a plurality of first mirrors are as efferent duct Mn1~Mnn and a plurality of second mirror image efferent duct Mp1~Mpn, described first mirror is as the second link of described the first amplifier tube M1 of the control termination of input pipe M3, described first mirror connects the second link of described the second mirror image input pipe M2 of termination as first of input pipe M3, described first mirror connects termination one supply voltage VDDA as second of input pipe M3, second of described the second mirror image input pipe M2 connects the second link of described the first amplifier tube M1 of termination, each described first mirror all connects described first mirror as the control end of input pipe M3 as the control end of efferent duct Mn1~Mnn, each described first mirror connects the described supply voltage VDDA of termination as second of efferent duct Mn1~Mnn, the control end of each described second mirror image efferent duct Mp1~Mpn all connects the control end of described the second mirror image input pipe M2, the described reference current Ib of rear output that links to each other of described the second mirror image efferent duct, the second link of each described second mirror image efferent duct Mp1~Mpn is connected with first link of a first mirror as efferent duct Mn1~Mnn.Described basic current circuit for generating 11 selects 6 trimming resistors, 6 road overriding image current modules and two-way high frequency low frequency to select the image current module to trim, and can trim the frequency shift (FS) that process deviation brings, and reaches the output frequency permissible accuracy.
Particularly, in the actual process production process, the temperature deviation of the output frequency fout of described built-in pierce circuit is got the main certainly temperature characterisitic of resistance and electric capacity after loop-locking.The temperature coefficient of electric capacity is at every degree centigrade 10 in actual process
-6Inferior magnitude, and the temperature coefficient of single resistance is 10
-3Inferior magnitude is so temperature coefficient is mainly determined by resistance-temperature characteristic.In order to reach-20 ℃~85 ℃ scopes 1% with interior deviation, need to compensate temperature coefficient of resistance, so trimming resistors selects the resistance R p of positive temperature coefficient and the resistance R n series complementary of negative temperature coefficient, so that trimming resistors is not subjected to the impact of temperature.
Produce circuit below in conjunction with the basic current shown in Fig. 3 .3 and be elaborated, because there are certain process deviation in resistance and electric capacity, so in order to reach our needed frequency, need to trim process deviation.The process deviation of described built-in oscillating circuit output frequency can be revised by trimming the position, realizes 0.1% the precision that trims.Trim precision for reaching 0.1% frequency, the frequency deviation brought of covering process voltage temperature deviation supposes that frequency deviation is ± 50% again, then needs at least log
2 (1000)=10bit control bit adds and (for example: 27M, 40M or 49M or 315M selects frequency range, 433M), for both can cover the scope of trimming, need to increase again 2bit and guarantee the adjacent fine tuning scope disconnected joint that overlaps each other, therefore need to require at least the control bit of 12bit.If single control adjustable resistance R or single control current mirror ratio, then chip area will be quite large all; If single employing control adjustable resistance needs 2 so
101024 pairs resistance, chip area equally can be quite large, for electric current too.Therefore, built-in oscillating circuit of the present invention adopts the method for the high-order control of current mirror and adjustable resistance low level fine tuning combination to save chip area, only needs adjustable resistance 2
6=64 pairs, image current 2
6=64 pairs, total area is much smaller than 1024 couple of single regulative mode.
Shown in Fig. 2 .2, described basic current produces circuit and receives a multidigit control signal, described multidigit control signal comprises frequency selection position, mirror image circuit is regulated position and resistance adjustment position, described frequency selects control some first mirrors in position to select to realize frequency range as the ratio value of input pipe M3 as efferent duct (Mn1 and Mn2) and described first mirror, described mirror image circuit is regulated all the other first mirrors of position control, and (to realize coarse adjustment in the frequency range, the resistance value of described trimming resistors (Rp+Rn) is controlled to realize accurate adjustment in the frequency range in described resistance adjustment position as the ratio value of input pipe M3 for Mn3~Mnn) and described first mirror as efferent duct.One encoder 18 produces the control signal D that circuit produces 14<13:0 to described basic current 〉, D<13:12 wherein〉select (00,01,10,11) for frequency; D<11:6〉be that mirror image circuit regulates the position; D<5:0〉be the resistance adjustment position; After the frequency of determining to export, select D<13:12〉value, for the frequency deviation of wanting covering process voltage temperature deviation to bring (suppose ± 50%), reach again 0.1% frequency and trim precision.Described circuitous resistance is realized 0.1% the precision that trims, and reaches in the coarse adjustment of image current place realization frequency to be about 0.64% precision.Suppose to realize frequency output fout, the resistance value of multichannel trimming resistors (Rp+Rn) is R so, and then the adjustable range of (Rp+Rn) is
Resistance adjustment position D<5:0 〉=000000---111111, the scope that frequency can reduce is 0.1%-6.4%, realizes accurate adjustment.Want the frequency deviation that covering process voltage temperature deviation brings (suppose ± 50%), the precision of image current is for being less than 6.4%, 100%/6.4%=15.6<24 so, can know needs 4 overriding positions at least, adopts 6 overriding circuit to make frequency coverage enough large here.Suppose base image electric current I ref=K*I1, add the size of coarse adjustment electric current, then image current Iref is:
Mirror image circuit is regulated a position D<11:6 〉=100000 o'clock frequencies are the centre frequency that requires, then D<11:6 〉=111111 be greatly and the frequency of centre frequency 50%, D<11:6 〉=000000 be the frequency less than centre frequency 50%.So just can cover total process deviation, can realize frequency output through trimming.
Frequency selects position (D<13:12 〉) control ratio to realize large electric current output, realizes the larger frequency shift of range.Want the frequency deviation that covering process voltage temperature deviation brings (suppose ± 50%), so total frequency deviation 100%/212=0.024% trims precision much smaller than 0.1% frequency.So just can cover total process deviation, can realize frequency output through trimming.
Wherein, the resistance of trimming resistors (Rp+Rn) expression positive temperature coefficient and the resistance addition of negative temperature coefficient, in the suitable situation of design, temperature coefficient is cancelled out each other.The first operational amplifier A 1 produces corresponding electric current I 1 according to input voltage Vb, the voltage Vbp of the control end of the second mirror image input pipe M2 is operated in the saturation region in order to guarantee the second mirror image input pipe M2 and first mirror as input pipe M3, the first operational amplifier A 1, the first amplifier tube M1 form negative feedback, in order to guarantee that the voltage that P is ordered among Fig. 3 .3 is input voltage Vb, the secondth mirror image input pipe M2 and first mirror are mirror as input pipe M3 and a plurality of first mirror as efferent duct Mn1~Mnn and a plurality of second mirror image efferent duct Mp1~Mpn.
The intermediate current I1 that can be got 11 generations of basic current generation circuit by upper analysis is: I1=Vb/ (Rp+Rn);
Can be got by mirror image circuit: Iref=K*I1;
Wherein, Vb represents described input voltage, (Rp+Rn) is the resistance value of trimming resistors, wherein Rp is the resistance of the positive temperature coefficient of trimming resistors, Rn represents the resistance of the negative temperature coefficient of trimming resistors, and the value of reference current Iref is directly proportional with I1, and K is proportionality coefficient; Then described basic current produces the reference current formula (1) that circuit 11 produces:
Iref=K*Vb/(Rp+Rn)------(1)
Fig. 4 .1~4.2 are the schematic diagram of built-in oscillating circuit medium frequency-electric current conversion circuit and electric current comparison amplifier in one embodiment of the invention.
Described frequency-electric current conversion circuit 15 comprises second operational amplifier A 2, the second amplifier tube M4, some switches, one charges and discharge electric capacity Cc, filter capacitor Cb and electric current output module, in the present embodiment, described switch comprises first K switch 1, second K switch 2.Described the second operational amplifier A 2 receives described input voltage Vb and exports the first end of described the second amplifier tube M4 to, described two K switch 1, K2 control respectively the described electric capacity Cc that charges and discharge and discharge and recharge the formation equivalent resistance module between the second end of described the second amplifier tube M4 and ground, the 3rd end of described the second amplifier tube M4 via described electric current output module after the described feedback current Iout of output, described filter capacitor Cb is used for that filtering is described to charge and discharge the high-frequency noise that electric capacity Cc produces.
Particularly, shown in Fig. 4 .1, in one embodiment, the electric current output module comprises the first efferent duct M6 and the second efferent duct M5, the electrode input end of described the second operational amplifier A 2 meets input voltage Vb, negative input connects the grid of the output termination second amplifier tube M4 of the source electrode P1 of the second amplifier tube M4 and filter capacitor Cb and first K switch 1, the second operational amplifier A 2.Another termination capacitor C c of first K switch 1 and second K switch 2, first K switch 1, second K switch 2 and charge and discharge the other end ground connection of electric capacity Cc, the other end of filter capacitor Cb is ground connection also.The drain electrode of the second amplifier tube M4 connects the drain electrode of source electrode and the first efferent duct M6 of the second efferent duct M5, and the drain electrode of the second efferent duct M5 links to each other with the source electrode of the first efferent duct M6, and the drain electrode of the first efferent duct M6 connects power supply.The grid of the second efferent duct M5 meets voltage Vp1, guarantees that the second efferent duct M5 and the first efferent duct M6 are operated in the saturation region.The second operational amplifier A 2 and the second amplifier tube M4 form negative feedback, the operating voltage that P1 is ordered among the assurance figure is Vb, first K switch 1 is by signal CLK1 control in the two-phase non-overlapping clock signal, K switch 2 is by another signal CLK2 control in the two-phase non-overlapping clock signal, during first K switch 1 conducting, second K switch 2 closed, wherein, described first K switch 1 and second K switch 2 are respectively by two-phase non-overlapping clock signal controlling, two-phase non-overlapping clock signal CLK1, CLK2 is two anti-phase not overlapped signals, two-phase non-overlapping clock signal CLK1, the frequency of CLK2 is identical with frequency signal fb behind the frequency division, thus conducting when preventing in frequency-electric current conversion circuit 15 two switches.
Accordingly, described current comparator comprises first mirror image tube M7, the second mirror image pipe M8, limit capacitor C 10 and a mirror image module, the control end of the described feedback current Iout of the control termination of described first mirror image tube M7 and described the first efferent duct, first of described first mirror image tube M7 connects the second link of described the second mirror image pipe M8 of termination, second of described first mirror image tube M7 connects termination one supply voltage VDDA, the control end of described the second efferent duct M5 of control termination of described the second mirror image pipe M8, first of described the second mirror image pipe M8 connects termination one output node, the described output node of first mirror picture input termination of described mirror image module, the described output current Ib of the second mirror image input termination, described capacitor C 10 two ends connect respectively described supply voltage and output node, and described output node is exported described feedback voltage V ctr.
Such as Fig. 4 .2, in another embodiment, the electric current output module comprises the first efferent duct M6, two inputs of described the second operational amplifier A 2 connect respectively the first link of described input voltage Vb and described the second amplifier tube M4, an and end of filter capacitor Cb and first K switch 1, the control end of the output termination second amplifier tube M4 of described the second operational amplifier A 2, the described end that charges and discharge electric capacity Cc and second K switch 2 of another termination of described first K switch 1, described second K switch 2, filter capacitor Cb and the equal ground connection of the other end that charges and discharge electric capacity Cc, second of described the second amplifier tube M4 connects the first link and the control end of termination the first efferent duct M6, second of the first efferent duct M6 connects termination one supply voltage VDDA, and the control end of described the first efferent duct M6 is exported described feedback current Iout.
Accordingly, described current comparator comprises first mirror image tube M7, limit capacitor C 10 and a mirror image module, the control end of the described feedback current Iout of the control termination of described first mirror image tube M7 and described the first efferent duct M6, first of described first mirror image tube M7 connects termination one supply voltage VDDA, second of described first mirror image tube M7 connects the described supply voltage of termination, the described output node of first mirror picture input termination of described mirror image module, the described output current Ib of the second mirror image input termination, described capacitor C 10 two ends connect respectively described supply voltage and output node, and described output node is exported described feedback voltage V ctr.
The principle of described frequency-electric current conversion circuit 15 is similar with the principle that Basic Flow produces circuit, and its resistance is realized in the mode of switching capacity resistance.Switching capacity resistance charges and discharge electric capacity Cc by one, two K switch 1, and K2 forms.Two K switch 1, K2 is subjected to two-phase non-overlapping clock signal CLK1, CLK2 control, when CLK1 was forward signal, CLK2 was reverse signal, then K1 conducting, K2 closes, and electric current charges to capacitor C c; When CLK1 was reverse signal, CLK2 was forward signal K2 conducting, and K1 closes, and the electric weight that P2 is ordered discharges over the ground by capacitor C c.The recharge discharge charges and discharge electric capacity Cc and produces the resistance that is equivalent to 1/ (fb*Cc).The effect of filter capacitor Cb is to filter the high-frequency noise that produces by charging and discharging electric capacity Cc.Can be known by the operating characteristic that charges and discharge electric capacity Cc, charge and discharge electric capacity Cc and be equivalent to resistance 1/fb*Cc, then described frequency-electric current conversion circuit with frequency translation be electric current shown in formula (2):
Iout=Vb*fb*Cc ------(2)
By the image current relation as can be known, Iout=I2, and I3=Ib.Wherein fb is the operating frequency of two-phase non-overlapping clock signal CLK1 and CLK2, and Vb is described input voltage, and Cc is the capacitance that charges and discharge electric capacity.When loop stability, Iout=Ib, output Vctr is stable, and frequency signal is stable.
With reference to figure 4.1, described electric current comparison amplifier 12, for the size that compares electric current I 2 and I3, by the image current relation as can be known, namely relatively feedback current Iout and output current Ib are big or small, and the control voltage Vctr of generation, with the frequency of adjusting ring oscillator.In the described electric current comparison amplifier, the mirror image module comprises the 9th metal-oxide-semiconductor M9 to the 12 metal-oxide-semiconductor M12, described first mirror image tube M7 and the second mirror image pipe M8 and the second efferent duct M5 and the first efferent duct M5 form the image current structure, the grid of described first mirror image tube M7 is connected with the grid of the first efferent duct M5, drain electrode connects supply voltage, source electrode connects the drain electrode of described the second mirror image pipe M8, the grid of described the second mirror image pipe M8 connects the grid of the second efferent duct M5, source electrode connects the drain electrode of described limit capacitor C 10 and the 9th metal-oxide-semiconductor M9 and connects described input voltage, the source electrode of described the 9th metal-oxide-semiconductor M9 connects the drain electrode of described the tenth metal-oxide-semiconductor M19, grid connects grid and the described output current of described the 12 metal-oxide-semiconductor M12, the source ground of described the tenth metal-oxide-semiconductor M10, grid connects the grid of described the 11 metal-oxide-semiconductor M11 and the source electrode of the 12 metal-oxide-semiconductor M12, the grounded drain of described the 11 metal-oxide-semiconductor M11, the drain electrode of described the 12 metal-oxide-semiconductor M12 connects described output current.Wherein limit capacitor C 10 produces a limit at control voltage Vctr output, thereby stablizes whole built-in oscillating circuit.When open-loop gain is enough large, during loop stability, Ib=Iout can be got by formula (1) (2),
Fout=M*fb again, then frequency signal is:
This shows that the variation of frequency signal fout and supply voltage VDD is irrelevant, temperature voltage technique (PVT) characteristic of frequency signal fout is determined by the temperature voltage operational characteristic of trimming resistors (Rp+Pn) and capacitor C c.Therefore, if overriding adjustable (Rp+Rn) and electric capacity (Cc) have less temperature coefficient, then the output signal frequency of voltage controlled oscillator also will have less temperature coefficient.
The temperature coefficient of electric capacity is at every degree centigrade 10 in actual process
-6Inferior magnitude, and the temperature coefficient of single resistance is 10
-3Inferior magnitude is so temperature coefficient is mainly determined by resistance-temperature characteristic.In order to reach-20 ℃~85 ℃ scopes 1% with interior deviation, temperature coefficient to the overriding adjustable resistance of multidigit compensates, select the resistance R p of positive temperature coefficient and the resistance R n series complementary of negative temperature coefficient, thereby further reduce the impact that trimming resistors is not subjected to temperature.
Fig. 5 is the schematic diagram of ring oscillator in the built-in oscillating circuit in one embodiment of the invention.As shown in Figure 5, described ring oscillator comprises multistage voltage controlled oscillator (VCO), form the difference channel of cascade, in the present embodiment, comprise that 4 grades of voltage controlled oscillators form 4 grades of cascade difference channels, 4 voltage controlled oscillators of described control voltage Vctr control are controlled the frequency signal fout of whole ring oscillator.Ring oscillator 13 of the present invention is to be convenient to integrated ring oscillator, and the controlled voltage Vctr control of its frequency signal fout is along with the minimizing frequency increase of control voltage Vctr.Thereby by selection ring oscillator structure with by suitable parameter designing, ring oscillator 13 has possibility and is operated in identical frequency under different temperatures.Wherein, the time of delay that the delay unit of ring oscillator 13 adopts positive feedback technique to come the control lag unit, thereby the frequency signal of change circuit.
Fig. 6 is the schematic diagram of many times of frequency dividers in the built-in oscillating circuit in one embodiment of the invention.As shown in Figure 6, described many times of frequency dividers 14 carry out frequency division with the frequency signal fout of ring oscillator 13, and to produce duty ratio be frequency signal fb behind 50% the output frequency division.Under specific technique, obtain higher frequency signal, the circuit performance that charges and discharge capacitor charge and discharge in frequency-electric current conversion circuit 15 can be affected, so by in the negative feedback cor-rection loop, increasing many times of frequency dividers 14, so that the switch frequency that charges and discharge electric capacity in frequency-electric current conversion circuit 15 is operated in after the frequency signal fb behind the frequency division, thereby guarantee the performance of frequency-electric current conversion circuit 15.In the present embodiment, many times of frequency dividers 14 comprise the twice frequency divider of a plurality of cascades, for example comprise n 2 frequency divider, then M=2
n, wherein M is the frequency division multiple of many times of frequency dividers 14.Wherein, described twice frequency divider can be by a d type flip flop and an inverter.
Table one is that clock signal generating circuit and novel built-in pierce circuit result compare schematic table, as shown in Table 1, clock signal generating circuit of the prior art need to arrange crystal oscillator outside sheet, and utilize crystal oscillator to produce vibration, therefore cost is higher, although and the frequency accuracy that the crystal oscillator of prior art produces circuit can reach 1ppm~100ppm, its frequency range can only be at 1KHz~100MHz.Than prior art, built-in oscillator of the present invention can all be arranged on the sheet, adopt ring oscillator control to produce frequency, therefore it has saved cost greatly, and by being set, many times of frequency dividers can greatly improve frequency range, reach 10KHz-450MHz and for example be widely used in various products, frequency range is at the toy remote control equipment of 27MHZ~49MHZ, and the wireless control apparatus of frequency range 315MHz or 433MHZ and frequency range are in the equipment such as infrared remote control equipment of 38KHz.
Table one
Crystal oscillator produces circuit | Built-in oscillator | |
Implementation method | Outside the sheet | On the sheet |
Oscillator | Crystal oscillator | Ring oscillator |
Frequency range | 1KHz-100MHz | 10KHz-450MHz |
Frequency accuracy | 1ppm-100ppm | 30ppm-100ppm |
Size of current | 10uA-100mA | 10uA-100mA |
Cost | High | Low |
In sum, built-in oscillating circuit of the present invention adopts negative feedback closed loop road form, utilize frequency-electric current transform mode, make the built-in oscillating circuit can be all integrated in chip, having omitted needs the outside extra crystal oscillator that arranges, saved process costs, and be converted into direct current by the frequency of oscillation that ring oscillator is produced, and produce the electric current that circuit produces with described basic current and compare, then comparative result is fed back to the control end of ring oscillator, change the frequency of ring oscillator, thereby compensate by the deviation to frequency signal, thereby make the operating frequency of loop stability output Low Drift Temperature, produce high-precision frequency signal.
Further, in the described built-in oscillating circuit, described basic current produces circuit and selects by the low level fine tuning of six trimming resistors and high position control and the high-order low bit frequency of the overriding current mirror of multichannel, thereby can be by trimming a modification method to the process deviation of frequency signal, reach 0.1% frequency and trim precision, and can cover the whole scope that trims, not disconnected joint.
Described built-in oscillating circuit has higher stability not only in technique in the situation of temperature deviation and supply voltage deviation, export a stable clock signal, and its frequency signal scope is wide.
Although the present invention discloses as above with preferred embodiment; so it is not to limit the present invention; have in the technical field under any and usually know the knowledgeable; without departing from the spirit and scope of the present invention; when can doing a little change and retouching, so protection scope of the present invention is as the criterion when looking claims person of defining.
Claims (21)
1. a built-in oscillating circuit is characterized in that, comprises that basic current produces circuit, ring oscillator, frequency-electric current conversion circuit and current comparator;
Described basic current produces circuit and comprises the first operational amplifier, the first amplifier tube, trimming resistors and mirror image circuit, described the first operational amplifier receives an input voltage, export an intermediate current by the first amplifier tube after described trimming resistors trims, described intermediate current is exported an output current through described mirror image circuit;
Described ring oscillator produces frequency signal;
Described frequency-electric current conversion circuit comprises the second operational amplifier, the second amplifier tube, some switches, charges and discharge electric capacity and electric current output module, described the second operational amplifier receives described input voltage and exports the first end of described the second amplifier tube to, described two switches are controlled respectively the described electric capacity that charges and discharge and are discharged and recharged the formation equivalent resistance module between the second end of described the second amplifier tube and ground, the 3rd end of described the second amplifier tube via described electric current output module after the described feedback current of output;
Output control voltage behind the more described feedback current of described current comparator and the described output current, described control voltage carries out feedback correction to the frequency signal that described ring oscillator produces, until the stable output of described frequency signal.
2. built-in oscillating circuit as claimed in claim 1 is characterized in that, during the stable output of the frequency signal of described ring oscillator, the value of described frequency signal is relevant with the capacitance that charges and discharge electric capacity with the resistance value that trims resistance.
3. built-in oscillating circuit as claimed in claim 2 is characterized in that, the output frequency of described built-in oscillator is:
Wherein, fout is the output frequency of described ring oscillator, and Cc is the described capacitance that charges and discharge electric capacity, (Rp+Rn) is the resistance value of described trimming resistors, and K is proportionality coefficient.
4. built-in oscillating circuit as claimed in claim 1, it is characterized in that, produce in the circuit at described basic current, two inputs of described the first operational amplifier connect respectively the first link of described reference voltage and the first amplifier tube, the control end of described the first amplifier tube of output termination; The first link of described trimming resistors one end ground connection, described the first amplifier tube of another termination, the second link, the output of described first amplifier tube of input termination of described mirror image circuit are exported described reference current.
5. built-in oscillating circuit as claimed in claim 4, it is characterized in that, described mirror image circuit comprises first mirror as efferent duct, described first mirror as the control end of described first amplifier tube of control termination of efferent duct, described first mirror as the first link of efferent duct export described reference current, described first mirror connects the described supply voltage of termination as second of efferent duct.
6. built-in oscillating circuit as claimed in claim 4, it is characterized in that, described mirror image circuit comprises that first mirror is as input pipe, the second mirror image input pipe, first mirror is as efferent duct and the second mirror image efferent duct, described first mirror is as the second link of described first amplifier tube of control termination of input pipe, described first mirror connects the second link of described the second mirror image input pipe of termination as first of input pipe, described first mirror connects termination one supply voltage as second of input pipe, second of described the second mirror image input pipe connects the second link of described the first amplifier tube of termination, described first mirror is as the described first mirror of control termination of the efferent duct control end as input, described first mirror connects the second link of described the second mirror image efferent duct of termination as first of efferent duct, described first mirror connects the described supply voltage of termination as second of efferent duct, the control end of the described second mirror image input pipe of control termination of described the second mirror image efferent duct, the first link of described the second mirror image efferent duct is exported described reference current, the second link of described the second mirror image efferent duct is connected with first link of a first mirror as efferent duct.
7. built-in oscillating circuit as claimed in claim 4, it is characterized in that, described mirror image circuit is the overriding mirror image circuit of multichannel, described trimming resistors is realized the adjusting of low level frequency departure to described reference current, and the overriding mirror image circuit of described multichannel realizes that high-order low bit frequency is selected and described reference current is realized high-order frequency departure adjusting.
8. built-in oscillating circuit as claimed in claim 7 is characterized in that, described overriding mirror image circuit is the common-source common-gate current mirror structure.
9. built-in oscillating circuit as claimed in claim 8, it is characterized in that, the overriding mirror image circuit of described multichannel comprises that first mirror is as input pipe, the second mirror image input pipe, a plurality of first mirrors are as efferent duct and a plurality of the second mirror image efferent duct, described first mirror is as the second link of described first amplifier tube of control termination of input pipe, described first mirror connects the second link of described the second mirror image input pipe of termination as first of input pipe, described first mirror connects termination one supply voltage as second of input pipe, second of described the second mirror image input pipe connects the second link of described the first amplifier tube of termination, each described first mirror all connects described first mirror as the control end of input pipe as the control end of efferent duct, each described first mirror connects the described supply voltage of termination as second of efferent duct, the control end of each described the second mirror image efferent duct all connects the control end of described the second mirror image input pipe, the described reference current of rear output that links to each other of described the second mirror image efferent duct, the second link of each described the second mirror image efferent duct is connected with first link of a first mirror as efferent duct.
10. built-in oscillating circuit as claimed in claim 1, it is characterized in that, described basic current produces circuit and receives a multidigit control signal, described multidigit control signal comprises frequency selection position, mirror image circuit is regulated position and resistance adjustment position, described frequency selects control some first mirrors in position to select to realize frequency range as the ratio value of input pipe as efferent duct and described first mirror, described mirror image circuit regulate all the other first mirrors of position control as efferent duct and described first mirror as the ratio value of input pipe to realize coarse adjustment in the frequency range, the resistance value of described trimming resistors is controlled with accurate adjustment in the realization frequency range in described resistance adjustment position.
11. built-in oscillating circuit as claimed in claim 1, it is characterized in that, described frequency-electric current conversion circuit also comprises filter capacitor, the described high-frequency noise that charges and discharge the electric capacity generation of described filter capacitor filtering, described switch comprises first switch and second switch, the electric current output module comprises the first efferent duct and the second efferent duct, two inputs of described the second operational amplifier connect respectively the first link of described input voltage and described the second amplifier tube, an and end of filter capacitor and first switch, the control end of output termination second amplifier tube of described the second operational amplifier, the described end that charges and discharge electric capacity and second switch of another termination of described first switch, described second switch, filter capacitor and the equal ground connection of the other end that charges and discharge electric capacity, second of described the second amplifier tube connects the first link of termination the second efferent duct and the control end of the first efferent duct, the second link of described the second efferent duct links to each other with the first link of the first efferent duct, second of the first efferent duct connects termination one supply voltage, the control end of described the first efferent duct is exported described feedback current, and described first switch and second switch are respectively by two-phase non-overlapping clock signal controlling.
12. built-in oscillating circuit as claimed in claim 11, it is characterized in that, described current comparator comprises the first mirror image tube, the second mirror image pipe, limit electric capacity and a mirror image module, the described feedback current of control termination of described first mirror image tube and the control end of described the first efferent duct, first of described first mirror image tube connects the second link of described the second mirror image pipe of termination, second of described first mirror image tube connects termination one supply voltage, the control end of described second efferent duct of control termination of described the second mirror image pipe, first of described the second mirror image pipe connects termination one output node, the described output node of first mirror picture input termination of described mirror image module, the described output current of the second mirror image input termination of described mirror image module, described output node is exported described feedback voltage.
13. built-in oscillating circuit as claimed in claim 1, it is characterized in that, described frequency-electric current conversion circuit also comprises filter capacitor, the described high-frequency noise that charges and discharge the electric capacity generation of described filter capacitor filtering, described switch comprises first switch and second switch, the electric current output module comprises the first efferent duct, two inputs of described the second operational amplifier connect respectively the first link of described input voltage and described the second amplifier tube, an and end of filter capacitor and first switch, the control end of output termination second amplifier tube of described the second operational amplifier, the described end that charges and discharge electric capacity and second switch of another termination of described first switch, described second switch, filter capacitor and the equal ground connection of the other end that charges and discharge electric capacity, second of described the second amplifier tube connects the first link and the control end of termination the first efferent duct, second of the first efferent duct connects termination one supply voltage, the control end of described the first efferent duct is exported described feedback current, and described first switch and second switch are respectively by two-phase non-overlapping clock signal controlling.
14. built-in oscillating circuit as claimed in claim 13, it is characterized in that, described current comparator comprises the first mirror image tube, limit electric capacity and a mirror image module, the described feedback current of control termination of described first mirror image tube and the control end of described the first efferent duct, first connects termination one output node, second connects termination one supply voltage, the described output node of one termination of described electric capacity, another termination supply voltage, the first mirror picture input termination output node of described mirror image module, the described output current of the second mirror image input termination, described output node is exported described feedback voltage.
15. built-in oscillating circuit as claimed in claim 1, it is characterized in that, described built-in oscillating circuit also comprises many times of frequency dividers, described many times of frequency dividers are arranged between described ring oscillator and the described frequency-electric current conversion circuit, after described many times of frequency dividers carry out frequency division to described frequency signal, export described frequency-electric current conversion circuit to, so that described frequency-voltage conversion circuit steady operation receives described frequency signal.
16. built-in oscillating circuit as claimed in claim 15 is characterized in that, when the stable output of described frequency signal, described frequency signal is:
Wherein, M is the frequency division multiple of described asynchronous frequency divider, and fout is the output frequency of described built-in oscillator, and Cc first charges and discharge the capacitance of electric capacity, (Rp+Rn) produces the resistance value of the trimming resistors of circuit for basic current, and K is proportionality coefficient.
17. built-in oscillating circuit as claimed in claim 15 is characterized in that, described many times of frequency dividers comprise the twice frequency divider of a plurality of cascades.
18. built-in oscillating circuit as claimed in claim 1 is characterized in that, described built-in oscillating circuit comprises that also one stablizes electric capacity, and described stable electric capacity one end is connected between described electric current comparison amplifier and the ring oscillator another termination supply voltage.
19., it is characterized in that described built-in oscillating circuit is arranged at frequency range at the toy remote control equipment of 27MHZ~49MHZ such as the described built-in oscillating circuit of any one in the claim 1 to 18.
20. such as the described built-in oscillating circuit of any one in the claim 1 to 18, it is characterized in that the wireless control apparatus of frequency range 315MHz or 433MHZ.
21., it is characterized in that frequency range is in the infrared remote control equipment of 38KHz such as the described built-in oscillating circuit of any one in the claim 1 to 18.
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4278947A (en) * | 1978-09-08 | 1981-07-14 | Bell Telephone Laboratories, Incorporated | Precision frequency source using integrated circuit elements |
CN201233548Y (en) * | 2008-07-25 | 2009-05-06 | 深圳市远望谷信息技术股份有限公司 | Voltage-current conversion circuit |
CN202363080U (en) * | 2011-11-08 | 2012-08-01 | 南京微盟电子有限公司 | Constant current LED drive circuit |
CN102783029A (en) * | 2009-12-30 | 2012-11-14 | 桑迪士克科技股份有限公司 | Temperature-stable oscillator circuit having frequency-to-current feedback |
CN202998064U (en) * | 2012-12-28 | 2013-06-12 | 杭州士兰微电子股份有限公司 | An internally-disposed oscillation circuit |
-
2012
- 2012-12-28 CN CN2012105926144A patent/CN103078635A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4278947A (en) * | 1978-09-08 | 1981-07-14 | Bell Telephone Laboratories, Incorporated | Precision frequency source using integrated circuit elements |
CN201233548Y (en) * | 2008-07-25 | 2009-05-06 | 深圳市远望谷信息技术股份有限公司 | Voltage-current conversion circuit |
CN102783029A (en) * | 2009-12-30 | 2012-11-14 | 桑迪士克科技股份有限公司 | Temperature-stable oscillator circuit having frequency-to-current feedback |
CN202363080U (en) * | 2011-11-08 | 2012-08-01 | 南京微盟电子有限公司 | Constant current LED drive circuit |
CN202998064U (en) * | 2012-12-28 | 2013-06-12 | 杭州士兰微电子股份有限公司 | An internally-disposed oscillation circuit |
Cited By (21)
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