Utility model content
The utility model embodiment provides a kind of power amplifier of adaptive supply voltage, to overcome the little problem of power amplifier power supply voltage usable range of the prior art.
The utility model first aspect provides a kind of power amplifier of adaptive supply voltage, comprising:
Voltage comparison module, for receiving the first supply voltage, comparing each reference voltage in described first supply voltage and multiple reference voltage respectively, obtaining multiple comparative result, and export described multiple comparative result to current settings module respectively;
Described current settings module, for receiving described multiple comparative result that described voltage comparison module exports, determining the output current value of described current settings module, and exporting described output current value to linear transconductance circuit module according to described multiple comparative result;
Described linear transconductance circuit module, for receiving the described output current value that described current settings module exports, according to the input voltage value of described output current value determination output level module, and exports described input voltage value to described output level module;
Described output level module, exports corresponding static working current value for the described input voltage value determined according to described linear transconductance circuit module;
Operation transconductance amplifier, the input of described operation transconductance amplifier connects signal to be amplified, and the output of described operation transconductance amplifier connects the input of described output level module.
In the first possible implementation of first aspect, described voltage comparison module comprises multiple hysteresis voltage comparator;
Multiple described hysteresis voltage comparator is connected in parallel, and the negative input end of each described hysteresis voltage comparator connects a reference voltage in described multiple reference voltage respectively, and the positive input terminal of each described hysteresis voltage comparator connects described first supply voltage.
In conjunction with the first possible implementation of first aspect, in the implementation that the second of first aspect is possible, described current settings module comprises switch element and sum unit;
Described switch element, for receiving the comparative result that each described hysteresis voltage comparator exports, and exports corresponding current value according to each described comparative result to described sum unit;
Described sum unit, the current value for the correspondence exported each described switch element is sued for peace, and obtains output current value.
In conjunction with the implementation that the second of first aspect is possible, in the third possible implementation of first aspect, described switch element comprises multiple switch, the input of each described switch is connected with the output of a hysteresis voltage comparator, the input of each described switch also connects an input current, and the output of each described switch is connected with described sum unit;
If the described comparative result that described hysteresis voltage comparator exports is 0, then described switch disconnects;
If the described comparative result that described hysteresis voltage comparator exports is 1, then described switch closes, to export the input current value of answering with described Switch Controller to described sum unit.
In the 4th kind of possible implementation of first aspect, described output level module comprises P-channel enhancement type metal oxide semiconductor field effect tube MOSFET and N channel enhancement MOSFET, and the drain electrode of described P-channel enhancement type MOSFET is connected with the drain electrode of described N channel enhancement MOSFET;
Described linear transconductance circuit module specifically for:
According to the described output current value that described current settings module is determined, determine the primary grid voltage that described P-channel enhancement type MOSFET is corresponding and second grid voltage corresponding to described N channel enhancement MOSFET;
The source electrode of described P-channel enhancement type MOSFET connects the second source voltage of setting, and described P-channel enhancement type MOSFET is connected with the drain electrode of described N channel enhancement MOSFET, the source ground of described N channel enhancement MOSFET.
In conjunction with the 4th kind of possible implementation of first aspect, in the 5th kind of possible implementation of first aspect, the output of described operation transconductance amplifier is connected with the grid of described P-channel enhancement type MOSFET and described N channel enhancement MOSFET.
In conjunction with the 5th kind of possible implementation of first aspect, in the 6th kind of possible implementation of first aspect, also comprise: output stage overcurrent protection module, for carrying out overcurrent protection to described P-channel enhancement type MOSFET and described N channel enhancement MOSFET;
The input of described output stage overcurrent protection module is connected with the drain electrode of described P-channel enhancement type MOSFET and described N channel enhancement MOSFET;
The output of described output stage overcurrent protection module is connected with the grid of described P-channel enhancement type MOSFET and described N channel enhancement MOSFET respectively.
In conjunction with in the 4th kind of possible implementation of first aspect, in the 7th kind of possible implementation of first aspect, described linear transconductance circuit module comprises:
First current source, the second current source, the first bias voltage generation module, the second bias voltage generation module, the first floating voltage module, the second floating voltage module, the first power supply and the second power supply;
The input of described first current source connects power supply, the output of described first current source connects the first bias voltage generation module and the first floating voltage module, the output of described first floating voltage module connects the grid of described P-channel enhancement type MOSFET, described first bias voltage generation module and described first floating voltage wired in parallel;
The input of described second current source connects power supply, the output of described second current source connects the second bias voltage generation module and the second floating voltage module, the output of described second floating voltage module connects the grid of described N channel enhancement MOSFET, described second bias voltage generation module and described second floating voltage wired in parallel.
The power amplifier of the adaptive supply voltage in the utility model, comprise: voltage comparison module, for receiving the first supply voltage, each reference voltage in described first supply voltage and multiple reference voltage is compared respectively, obtain multiple comparative result, and export described multiple comparative result to current settings module respectively; Described current settings module, for receiving described multiple comparative result that described voltage comparison module exports, determining the output current value of described current settings module, and exporting described output current value to linear transconductance circuit module according to described multiple comparative result; Described linear transconductance circuit module, for receiving the described output current value that described current settings module exports, determining the input voltage value of described output level module, and exporting described input voltage value to output level module according to described output current value; Described output level module, exports corresponding static working current value for the described input voltage value determined according to described linear transconductance circuit module; Operation transconductance amplifier, the input of described operation transconductance amplifier connects signal to be amplified, and the output of described operation transconductance amplifier connects the input of described output level module.
Wherein, voltage comparison module can obtain different comparative results according to the different value of input supply voltage, thus make current settings module can obtain different current values, finally make linear transconductance circuit module can determine the different grid voltages of output stage according to different current values, thus make output stage export different static working current values, the scope of the supply voltage of the power amplifier of effective expansion, further expands the range of application of power amplifier.
Embodiment
For making the object of the utility model embodiment, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in the utility model embodiment, technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.
The structural representation of the power amplifier of the adaptive supply voltage that Fig. 1 provides for the utility model embodiment, as shown in Figure 1, the power amplifier 100 of described adaptive supply voltage can comprise:
Voltage comparison module 101, for receiving the first supply voltage, each reference voltage in described first supply voltage and multiple reference voltage is compared respectively, obtains multiple comparative result, and export described multiple comparative result to current settings module 102 respectively.
Optionally, as shown in Figure 2, voltage comparison module 101 can comprise multiple hysteresis voltage comparator 1011, and multiple hysteresis voltage comparator 1011 is connected in parallel, according to the difference of practical application scene, multiple different reference voltage can be set, and the negative input end of each described hysteresis voltage comparator 1011 connects a reference voltage in multiple reference voltage respectively, concrete, first supply voltage can carry out dividing potential drop through resistance R1 and resistance R2, also be, the magnitude of voltage that what the positive input terminal of each described hysteresis voltage comparator 1011 connected is after the dividing potential drop of the first supply voltage, wherein, value after first source voltage of the positive input terminal connection of hysteresis voltage comparator 1011
wherein, V
init is the magnitude of voltage of the first supply voltage.
Wherein, arrange the object with sluggish comparator in voltage comparison module 101 be impact in order to avoid the voltage dithering on power line and noise and cause power tube switching back and forth between different states.
It should be noted that the difference of the reference voltage that the negative input end of adjacent two hysteresis voltage comparators 1011 connects should be greater than the hysteresis voltage value of hysteresis voltage comparator 1011.
Optionally, for each in multiple hysteresis voltage comparator 1011, when negative input end connect reference voltage be greater than positive input terminal connect dividing potential drop after the first supply voltage, the output output low level of described hysteresis voltage comparator 1011, also be, the output of hysteresis voltage comparator 1011 exports " 0 ", when negative input end connect reference voltage be less than positive input terminal connect dividing potential drop after the first supply voltage, the output of described hysteresis voltage comparator 1011 exports high level, also namely, the output of hysteresis voltage comparator 1011 exports " 1 ".
Described current settings module 102, for receiving described multiple comparative result that described voltage comparison module 101 exports, determine the output current value of described current settings module 102 according to described multiple comparative result, and export described output current value to linear transconductance circuit module 103.
Optionally, as shown in Figure 3, described current settings module 102 can comprise switch element 1021 and sum unit 1022, described switch element 1021, comprise multiple switch, for receiving the comparative result that each described hysteresis voltage comparator 1011 exports, and export corresponding current value according to each described comparative result to described sum unit 1022;
Described sum unit 1022, for suing for peace to the current value of the correspondence exported each described switch element 1021, obtains output current value.
Concrete, described switch element 1021 comprises multiple switch, the input of each described switch is connected with the output of a hysteresis voltage comparator 1021, and the input of each described switch also connects an input current, and the output of each described switch is connected with described sum unit 1022; Wherein, input 1, input 2 ... input N is respectively the Output rusults of corresponding hysteresis voltage comparator 1011, electric current 1, electric current 2 ... electric current N is respectively the current value that should export sum unit 1022 after corresponding switch closes to.
If the described comparative result that described hysteresis voltage comparator 1011 exports is 1, then described switch closes; If described comparative result is 0, then described switch disconnects, and the corresponding current value of circuit that each Switch Controller is answered, after switch is closed, the input current value that this way switch is corresponding exports sum unit 1022 to, to make described sum unit 1022 according to described current value, try to achieve the current value that current settings module 102 should export.
In the attainable mode of one of the present utility model, the producing method of the input current of the input connection of each switch can be as shown in Figure 4, wherein, bias current can be produced by current biasing circuit, electric current 1, electric current 2 ... electric current N is the current value obtained according to certain scaled mirror by bias current by current mirror, the ratio of its mirror image can regulate according to practical application scene, the utility model is not limited it, further, the utility model is not limited the producing method of the input current that the input of each switch connects.
Such as, 3 hysteresis voltage comparators are had in voltage comparison module, be respectively CMP1, CMP2 and CMP3, then there are three switches in current settings module, be respectively S1, S2 and S3, wherein, the input of S1 is connected with the output of CMP1, the input of S2 is connected with the output of CMP2, the input of S3 is connected with the output of CMP3, S1, the output of S2 and S3 is all connected to sum unit, suppose S1, after S2 and S3 is closed, the current value that place circuit correspondence flows through is 1 μ A, and the output of CMP1 is low level 0, the output of CMP2 is high level 1, the output of CMP3 is high level 1, then according to CMP1, the Output rusults of CMP2 and CMP3 is known, S1 disconnects, S2 and S3 closes, circuit communication corresponding to S2 and S3, electric current flow to sum unit, sum unit now determines that the output current of current settings module is the current value sum flowed through that S2 and S3 place circuit is corresponding, also be 2 μ A.
It should be noted that in actual applications, after each switch is closed, the current value that circuit correspondence in each switch place flows through can be different, and after the utility model is not closed to each switch, the size of the current value flowed through is limited.
Described linear transconductance circuit module 103, for receiving the described output current value that described current settings module 102 exports, determine the input voltage value of described output level module 104 according to described output current value, and export described input voltage value to output level module 104.
Described output level module 104, exports corresponding static working current value for the described input voltage value determined according to described linear transconductance circuit module 103.
Optionally, as shown in Figure 2, described output level module 104 comprise P-channel enhancement type metal oxide semiconductor field effect tube (Metal-Oxide-Semiconductor Field-Effect Transistor, referred to as: MOSFET), hereinafter referred to as MP; N channel enhancement MOSFET, hereinafter referred to as MN.The drain electrode of described MP is connected with the drain electrode of described MN.
Optionally, described linear transconductance circuit module 103, specifically for the described output current value determined according to described current settings module 102, determines the primary grid voltage that described MP is corresponding and second grid voltage corresponding to described MN;
The source electrode of described MP connects the second source voltage of setting, and described MP is connected with the drain electrode of described MN, the source ground of described MN.
Concrete, according to above-mentioned description, when the output of power amplifier does not connect load, the electric current of MP flows into the drain electrode of MN by the drain electrode of MP, then the source electrode through MN flows into ground, and also, current value is now the static working current value of power amplifier.
Further, as shown in Figure 5, described linear transconductance circuit module 103 can comprise:
First bias voltage generation module 1031a, the second bias voltage generation module 1031b, the first floating voltage module 1032a, the second floating voltage module 1032b, the first current source 1033a, the second current source 1033b, linear transconductance circuit module power supply 1034;
The input connecting linear conduction-cross circuit module power supply 1034 of described first bias voltage generation module 1031a, the input of described first current source 1033a connects the output of the first bias voltage generation module 1031a and the input of the first floating voltage module 1032a, the output head grounding of described first current source 1033a, the output of described first floating voltage module 1032a connects the grid of the MP of output level module 104;
The input connecting linear conduction-cross circuit module power supply 1034 of described second current source 1033b, the output of described second current source 1033b connects the input of the second bias voltage generation module 1031b and the input of the second floating voltage module 1032b, and the output of described second floating voltage module 1032b connects the grid of the MN of output level module 104.
Wherein, the current value that the first current source 1033a and the second current source 1033b sets is the output current value that current settings module 102 is determined.
Such as, when the output current value of current settings module setting is 2 μ A, then now the current value of 2 μ A flows into linear conduction-cross circuit module, the bias voltage V that the first bias voltage generation module in linear conduction-cross circuit module in the corresponding linear transconductance circuit module of the current value of 2 μ A and the second bias voltage generation module produce
bIAS1and V
bIAS2be 2V, the voltage VF1 of the first floating voltage module is the voltage of 1.4V and the second floating voltage module be VF2 is 0.5V, and voltage VDD1 and VDD2 of linear transconductance circuit module power supply is respectively 12V, then the grid voltage that MN is corresponding is V
bIAS1the magnitude of voltage that the grid that-VF1=0.6V, MP are corresponding is corresponding is VDD-V
bIAS2+ VF2=10.5V.
It should be noted that, the circuit structure of the structural representation of modules involved in the utility model embodiment, the circuit components that can change circuit components wherein according to the demand of reality or increase wherein, as long as it can reach the Output rusults in this utility model embodiment required for modules.
Operation transconductance amplifier 105, the input of described operation transconductance amplifier 105 connects signal to be amplified, and the output of described operation transconductance amplifier 106 connects the input of described output level module 104.
Optionally, the output of described operation transconductance amplifier 105 is connected with the grid of described MP and described MN.
In the application of reality, the input of the operation transconductance amplifier 105 of output level module 104 front portion can connect signal to be amplified, makes the signal to be amplified after the output output processing of output level module 104, also, exports the signal after amplifying.
Concrete, described operation transconductance amplifier 105 and output level module 104 form the power amplifier with secondary enlarging function, first the signal to be amplified of input can be carried out anti-phase amplification by operation transconductance amplifier 105, then the signal after anti-phase amplification is inputed to output level module 104 and carry out secondary amplification, output level module 104 carries out anti-phase amplification again to the signal after amplification, now just can export the signal after the amplification identical with signal phase to be amplified.
Further, as shown in Figure 1, the merit power amplifier 100 of described adaptive supply voltage also comprises: output stage overcurrent protection module 106, for carrying out overcurrent protection to described MP and described MN.
Concrete, the input of described output stage overcurrent protection module 106 is connected with the drain electrode of described MP and described MN, and the output of described output stage overcurrent protection module 106 is connected with the grid of described MP and described MN respectively.
Further; as shown in Figure 6; described output stage overcurrent protection module 106 specifically comprises: power tube current sample rate current 1061, power tube maximum current initialization circuit 1062 and control circuit 1063; wherein the sample mode of the actual output current of power tube sample circuit 1061 pairs of power tubes can be: sampled by the voltage drained to power tube, just can learn the actual output current value I of power tube
actual, and power tube maximum current initialization circuit 1062 is for determining power tube exportable lowest high-current value I in normal operation
max, control circuit 1063 is for comparing I
actualwith I
maxmagnitude relationship, and control the working method of grid of power tube according to magnitude relationship, work as I
actualbe greater than I
maxtime, control circuit 1063 will switch-off power pipe, also, the grid voltage of MN pipe is pulled to low level, the grid voltage of MP pipe is pulled to high level, and works as I
actualbe less than I
maxtime, control circuit 1063 does not do any process to power tube.
Concrete, suppose in the prior art, when the magnitude of voltage after source voltage is less than 1.154V, power amplifier output-stage automatically shuts down; When the magnitude of voltage after source voltage is greater than 1.154V+Vsys, power amplifier output-stage conducting (wherein Vsys is hysteresis voltage).For above-mentioned power amplifier of the prior art, the utility model embodiment provides a kind of concrete execution mode, for expanding the scope of application of the supply voltage of above-mentioned prior art intermediate power amplifier, 4 hysteresis voltage comparators are set in the present embodiment, be respectively CMP1, CMP2, CMP3 and CMP4, and 4 different reference voltages are set, represent below with reference to voltage Vref, concrete, 4 reference voltages arranged in the present embodiment are respectively Vref1, Vref2, Vref3 and Vref4, the negative input end of CMP1 connects Vref1, the negative input end of CMP2 connects Vref2, the negative input end of CMP3 connects Vref3, the negative input end of CMP4 connects Vref4, suppose that the hysteresis voltage of hysteresis voltage comparator is 20mV, and the difference of the reference voltage that adjacent two hysteresis voltage comparator negative input ends connect is 64mV, i.e. Vref1=0.962V, Vref2=1.026V, Vref3=1.090V, Vref4=1.154V, value after the source voltage that the positive input terminal of hysteresis voltage comparator connects is 1.054V, value 1.054V now after source voltage is less than 1.154V, will direct switch-off power amplifier output stage in prior art, power amplifier quits work, and the power amplifier of the adaptive supply voltage that the utility model provides, when the value after source voltage is 1.054V, power amplifier still works, and do not turn off, be specially:
For CMP1, the reference voltage level that negative input end connects is 0.962V, value after the source voltage that positive input terminal connects is 1.054V, and negative input end connect reference voltage level 0.962V be less than positive input terminal connect source voltage after value 1.054V, then the output of CMP1 exports high level, also namely exports " 1 ", for CMP2, the reference voltage level that negative input end connects is 1.026V, value after the source voltage that positive input terminal connects is 1.054V, and negative input end connect reference voltage level 1.026V be less than positive input terminal connect source voltage after value 1.054V, then the output of CMP2 exports high level, also namely " 1 " is exported, the comparing class of CMP3 and CMP4 and CMP1 and CMP2 seemingly, do not repeat one by one herein, then, the output output low level of CMP3, also namely " 0 " is exported, the output output low level of CMP4, also namely " 0 " is exported, switch corresponding with CMP1 in current settings module closes, the switch corresponding with CMP2 closes, the switch corresponding with CMP3 disconnects, the switch corresponding with CMP4 disconnects, after supposing that switch that CMP1 is corresponding is closed, the current value that this switch place circuit passes through is I
1after the switch that=10 μ A, CMP2 are corresponding is closed, the current value that this switch place circuit passes through is I
2=10 μ A, then the output current value of current settings module is I
1and I
2sum, i.e. 20 μ A, then this current value is inputed to linear transconductance circuit module, the input voltage value that linear transconductance circuit module is corresponding according to the grid of MP and MN in the current value determination output level module of input is 10.5V and 0.6V, and now the static working current value of output level module is 50 μ A.According to above-mentioned analysis, when the supply voltage being divided to described power amplifier is less than 1.154V, the power amplifier that the utility model provides still can normally use, and the current value just now exported is less than the current value when the supply voltage being divided to described power amplifier is 1.154V.
The utility model embodiment provides a kind of power amplifier of adaptive supply voltage, comprise: voltage comparison module, for receiving the first supply voltage, each reference voltage in described first supply voltage and multiple reference voltage is compared respectively, obtain multiple comparative result, and export described multiple comparative result to current settings module respectively; Described current settings module, for receiving described multiple comparative result that described voltage comparison module exports, determining the output current value of described current settings module, and exporting described output current value to linear transconductance circuit module according to described multiple comparative result; Described linear transconductance circuit module, for receiving the described output current value that described current settings module exports, determining the input voltage value of described output level module, and exporting described input voltage value to output level module according to described output current value; Described output level module, exports corresponding static working current value for the described input voltage value determined according to described linear transconductance circuit module; Operation transconductance amplifier, the input of described operation transconductance amplifier connects signal to be amplified, and the output of described operation transconductance amplifier connects the input of described output level module.
Wherein, voltage comparison module can obtain different comparative results according to the different value of input supply voltage, thus make current settings module can obtain different current values, finally make linear transconductance circuit module can determine the different grid voltages of output stage according to different current values, thus make output stage export different static working current values, the scope of the supply voltage of the power amplifier of effective expansion, further expands the range of application of power amplifier.
Last it is noted that above each embodiment is only in order to illustrate the technical solution of the utility model, be not intended to limit; Although be described in detail the utility model with reference to foregoing embodiments, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein some or all of technical characteristic; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of each embodiment technical scheme of the utility model.