CN102495265B - Current sampling circuit of metal oxide semiconductor field effect transistor (MOSFET) switch element - Google Patents
Current sampling circuit of metal oxide semiconductor field effect transistor (MOSFET) switch element Download PDFInfo
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- CN102495265B CN102495265B CN201110391321.5A CN201110391321A CN102495265B CN 102495265 B CN102495265 B CN 102495265B CN 201110391321 A CN201110391321 A CN 201110391321A CN 102495265 B CN102495265 B CN 102495265B
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Abstract
The invention discloses a current sampling circuit of a metal oxide semiconductor field effect transistor (MOSFET) switch element. A first end of the switch element is connected with a first input end of a sampling module and serves as a current input signal end, a second end of the switch element is connected with a second input end of the sampling module and serves as a current output signal end of the MOSFET switch element, and an output end of the sampling module serves as a sampling current output signal end. The sampling module directly samples voltage difference of the first end and the second end of the MOSFET switch element. Maximum voltage difference value allowed between the first input end and the second input end of the sampling module is a withstand voltage value between two input ends of the sampling module. A clamping module included in the sampling module increases the withstand voltage value of the sampling module so that a current path formed between the first input end and the second input end of the sampling module is blocked, and working voltage range of the current sampling circuit of the MOSFET switch element is improved.
Description
Technical field
The present invention relates to the current sample technology in electric power management circuit, more precisely, relate to a kind of technology and current sampling circuit of sampling by the electric current of switch mosfet element conductive resistance.
Background technology
The application of electric power management circuit is very extensive, most electric power management circuits all need built-in or external switch mosfet element, and detect the current value that flows through switch mosfet element, obtain the voltage signal relevant with this current value or current signal, according to unlatching and the shutoff of this voltage signal or current signal control switch mosfet element.
Figure 1A is depicted as the current sampling circuit of typical switch mosfet element, sample streams is crossed the current value of switch mosfet element 1 in this circuit: described on-off element is P channel mosfet on-off element, the first end of switch mosfet element connects the output terminal of sampling element 02 and the second input end of sampling module 03, and the second end of described on-off element is as current output signal end; The input end of described sampling element 02 is connected with the first input end of sampling module 03, and as current input signal end.
The principle of the current sampling circuit of the element of switch mosfet shown in Figure 1A is, approximate think flow through the electric current I of switch mosfet element
oUTwith the electric current I that flows through the sampling element being connected with switch mosfet element
iNequate, by detecting the voltage difference on sampling element, sampling module detects and flows through the size of current of sampling element and export sample rate current signal IO.
The specific implementation of the current sampling circuit of the element of switch mosfet shown in Figure 1A and application as shown in Figure 1B: described switch mosfet element 01 is P raceway groove the first metal-oxide-semiconductor M1; Described sampling element 02 is resistance R 0, the substrate terminal of one end of resistance R 0 and the first metal-oxide-semiconductor M1 and the first input end of described electric current and voltage modular converter 03 are connected, and as current input signal end, the output terminal of resistance R 0 connects the source of the first metal-oxide-semiconductor M1 and the second input end of sampling module 03;
Described sampling module 03 comprises the first resistance R 1, the second resistance R 2, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4, constant current source I03 and constant current source I04 composition, the first resistance R 1 equals the second resistance R 2, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, and the electric current of constant current source I03 equals the electric current of constant current source I04.
One end of one end of the first resistance R 1 and sampling element R0 and the substrate terminal of the first metal-oxide-semiconductor M1 are connected, and as current input signal end, one end of the second resistance R 2 connects the other end of sampling element R0 and the source of the first metal-oxide-semiconductor M1, and the other end of the first resistance R 1 is connected with source, the substrate terminal of the 3rd PMOS pipe M3 and as the current output signal end of the current sampling circuit of switch mosfet element; The sample rate current I05 of current output signal end output is by the signal of more controlled on-off element the first metal-oxide-semiconductor M1 of benchmark in control chip.
Suppose that the electric current I 01 that flows through the first metal-oxide-semiconductor M1 meets I01 > > I03 with the electric current I 02 that flows through the resistance R 0 being connected with the first metal-oxide-semiconductor M1, I02 > > I03, flow through the electric current I 01 and electric current I 02 approximately equal that flows through the resistance R 0 being connected with the first metal-oxide-semiconductor M1 of the first metal-oxide-semiconductor M1, I01 ≈ I02, the voltage V0=R0 × I01 on sampling element R0;
I03=I04, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, so the source voltage terminal of the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 meets Vs3=Vs4;
Voltage VR1=(I03+I05) × R1 in the first resistance R 1, voltage VR2=I04 × R2 in the second resistance R 2, VR1-VR2=I02 × R0 (being the voltage in resistance R 0), so (I03+I05) × R1-I04 × R2=I02 × R0, I03=I04, R1=R2, I01 ≈ I02 again, so I05 × R1=I02 × R0, I05=I01 × R0/R1.By the current sampling circuit output of switch mosfet element and the corresponding current signal I05 of electric current I 01 of on-off element the first metal-oxide-semiconductor M1, the sample rate current I05 of output is by the signal of more controlled on-off element the first metal-oxide-semiconductor M1 of benchmark in control chip.
The current sampling circuit of above-mentioned switch mosfet element, be applied to when external switch mosfet element is carried out to current sample, peripheral circuit need to increase extra sampling element, be generally resistance, take Figure 1B as example, because the electric current I 01 that flows through the first metal-oxide-semiconductor M1 has caused voltage loss on sampling element R0, the voltage in resistance R 0 is I02 × R0, and its power attenuation is Pdis=I02 × R0 × I02=(I01)
2× R0; Conventionally the value of the electric current I 01 of inflow on-off element the first metal-oxide-semiconductor M1 is larger, thereby has increased extra power attenuation.And be applied to when built-in switch mosfet element is carried out to current sample, conventionally adopt aluminum strip connection resistances as sampling element, although need not increase extra element.But built-in switch mosfet element is subject to process technology limit, and the conducting resistance of switch mosfet element is large, and efficiency is low, and majority can only be used for miniwatt product.The driving control chip and the switch mosfet element that adopt at present are in addition often discrete device, close the method that is encapsulated in a packaging body by encapsulation, and switch mosfet element adopts high performance MOSFET on-off element, therefore can improve the efficiency of whole integrated circuit.But close encapsulation method due to the restriction being encapsulated, be not suitable for increasing sampling element, therefore cannot adopt the current sampling circuit of above-mentioned switch mosfet element.
Summary of the invention
The present invention will solve the deficiencies in the prior art, and a kind of clamper module switch mosfet element current Sampling techniques are provided, and utilizes the conducting resistance of switch mosfet element to detect the size of current flowing through wherein; And by increasing clamper module, improve the maximum admissible voltage difference of sampling module first input end and the second input end, improve the operating voltage range of the current sampling circuit of switch mosfet element.
The conducting resistance Ron itself existing when the present invention utilizes on-off element switch mosfet element conductive is as sampling element, in the time of switch mosfet element conductive, the electric current that flows through switch mosfet element can produce voltage difference by conducting resistance Ron between the first end of switch mosfet element and the second end.
A current sampling circuit for switch mosfet element, comprises switch mosfet element and sampling module:
Described switch mosfet element is P channel mosfet on-off element, the first end of described on-off element is connected with the first input end of sampling module, and as current input signal end, the second end of described on-off element and the second input end of sampling module are connected, and as switch mosfet element current output signal end, the output terminal of described sampling module is as the sample rate current output signal end of the current sampling circuit of switch mosfet element, the first end of described sampling module Direct Sampling switch mosfet element and the voltage difference of the second end, between the first input end of described sampling module and the second input end, admissible maximum voltage difference is the withstand voltage between two input ends of sampling module,
Described sampling module comprises clamper module, described clamper module increases the withstand voltage between sampling module first input end and the second input end, blocking-up forms current path from the first input end end of sampling module to the second input end, improves the operating voltage range of the current sampling circuit of switch mosfet element.
Described MOSFET current sampling circuit, a kind of specific implementation is:
Described switch mosfet element is P raceway groove the first metal-oxide-semiconductor M1, the first end of switch mosfet element 11 is source, the second end of switch mosfet element is drain terminal, the source of the first metal-oxide-semiconductor M1 is connected the first input end of sampling module with substrate, and as current input signal end, the drain terminal of the first metal-oxide-semiconductor M1 connects the second input end of sampling module and as switch mosfet element current output signal end, the grid end of the first metal-oxide-semiconductor M1 is inputted grid control signal;
Described sampling module comprises clamper module, the first resistance R 1, the second resistance R 2, the three PMOS pipe M3, the 4th PMOS pipe M4, the first constant current source I13, the second constant current source I14 of the second diode D2 composition of the first diode D1, N series connection of N series connection;
The forward end of the first diode D1 and the source of the first metal-oxide-semiconductor M1 of N series connection are connected with substrate, and as current input signal end, the forward end of the second diode D2 of N series connection is connected with the drain terminal of the first metal-oxide-semiconductor M1, and as switch mosfet element current output signal end, the backward end of the first diode D1 of N series connection is connected with one end of the first resistance R 1, the backward end of the second diode D2 of N series connection is connected with one end of the second resistance R 2, the other end of the first resistance R 1 is connected with substrate with the source of the 3rd PMOS pipe M3 and as sample rate current output signal end, the other end of the second resistance R 2 is connected with source, the substrate terminal of the 4th PMOS pipe M4, the grid of the drain terminal of the 3rd metal-oxide-semiconductor M3, the grid of the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 is connected with the first constant current source I13, and the drain terminal of the 4th metal-oxide-semiconductor M4 is connected with the second constant current source I14.
Between the first input end of described sampling module and the second input end, maximum admissible voltage difference is V
dSMAX2:
V
dSMAX2=V
mAX1+ (I13+I15) × R1+I14 × R2+N × VF1+N × VD2=V
mAX1+ 2 × I13 × R1+I15 × R1+N × VF1+N × VD1 is wherein:
V
mAX1leak in the source that is the 3rd metal-oxide-semiconductor M3, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage;
I13 is the first constant current source;
I14 is the second constant current source;
I15 is sample rate current;
R1 is the first resistance;
R2 is the second resistance;
VF1 is the first diode D1 forward voltage drop;
VD1 is the first diode D1 breakdown reverse voltage;
The breakdown reverse voltage of VD2 the second diode D2;
N is equal to, or greater than 1 positive integer.
Above-mentioned MOSFET current sampling circuit, described N is 1 or 3.
Another specific implementation of MOSFET current sampling circuit is:
Described switch mosfet element is P raceway groove the first metal-oxide-semiconductor M1, the first end of switch mosfet element is source, the second end of switch mosfet element is drain terminal, the source of the first metal-oxide-semiconductor M1 is connected the first input end of sampling module with substrate terminal, and as current input signal end, the drain terminal of the first metal-oxide-semiconductor M1 connects the second input end of sampling module and as switch mosfet element current output signal end, the grid end of the first metal-oxide-semiconductor M1 is inputted grid control signal;
Described sampling module comprises clamper module, the first resistance R 1, second resistance R 2 of the second diode D2 composition of the first diode D1, N series connection of N series connection, the 3rd PMOS pipe M3, the 4th PMOS pipe M4, the first constant current source I13, the second constant current source I14, the first resistance R 1 equals the second resistance R 2, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, and the first constant current source I13 equals the second constant current source I14;
The source of one end of the first resistance R 1 and the first metal-oxide-semiconductor M1 is connected with substrate terminal, and as current input signal end, one end of the second resistance R 2 is connected with the drain terminal of the first metal-oxide-semiconductor M1 and as switch mosfet element current output signal end, the other end of the first resistance R 1 is connected with the forward end of the first diode D1 of N series connection and as the sample rate current output signal end of the current sampling circuit of switch mosfet element, the other end of the second resistance R 2 is connected with the forward end of the second diode D2 of N series connection, the backward end of the first diode D1 of N series connection is connected with substrate with the source of PMOS pipe the 3rd metal-oxide-semiconductor M3, the backward end of the second diode D2 of N series connection is connected with substrate with the source of the 4th PMOS pipe M4, the drain terminal of the 3rd metal-oxide-semiconductor M3, the 3rd metal-oxide-semiconductor M3, the grid of the 4th metal-oxide-semiconductor M4 is connected with the first constant current source I13, the drain terminal of the 4th metal-oxide-semiconductor M4 is connected with the second constant current source I14.
Above-mentioned MOSFET current sampling circuit, between the first input end of described sampling module and the second input end, maximum admissible voltage difference is V
dSMAX2:
V
dSMAX2=V
mAX1+ (I13+I15) × R1+I14 × R2+N × VF1+N × VD2=V
mAX1+ 2 × I13 × R1+I15 × R1+N × VF1+N × VD1 is wherein:
V
mAX1leak in the source that is the 3rd metal-oxide-semiconductor M3, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage;
I13 is the first constant current source;
I14 is the second constant current source;
I15 is sample rate current;
R1 is the first resistance;
R2 is the second resistance;
VF1 is the first diode D1 forward voltage drop;
VD1 is the first diode D1 breakdown reverse voltage;
The breakdown reverse voltage of VD2 the second diode D2;
N is equal to, or greater than 1 positive integer.
Described N is 1 or 3
Sampling techniques provided by the invention, can Direct Sampling switch mosfet element first end and the voltage difference of the second end, and the conversion output current signal corresponding with the electric current of on-off element.Without sampling element, also remove the power attenuation on sampling element compared to existing technology, particularly can be applied to and drive control chip and switch mosfet element to close the integrated circuit of envelope simultaneously.
Switch mosfet element current Sampling techniques provided by the invention, the voltage difference of current sample module Direct Sampling switch mosfet element input end and output terminal.Between the first input end of sampling module and the second input end, admissible maximum voltage difference is the withstand voltage between two input ends of sampling module.In the time of high-pressure work, due to the switch mosfet element being operated under switching mode, under off state, the voltage difference of input end and output terminal is very high, can exceed the withstand voltage between two input ends of sampling module, sampling module first input end forms electric leakage path to meeting between the second input end, thereby the operating voltage range of the current sampling circuit of switch mosfet element is restricted.Therefore in current sample module, increase clamper module, utilize the clamper function of the reverse voltage of diode to increase the withstand voltage between two input ends of sampling module, blocking-up is from sampling module first input end to forming electric leakage path the second input end, thus the operating voltage range of the current sampling circuit of raising switch mosfet element.
The invention has the beneficial effects as follows: the not only output current signal corresponding with the electric current of on-off element, without sampling element, also remove the power attenuation on sampling element simultaneously; And by clamper module, improved the maximum admissible voltage difference of sampling module first input end and the second input end, improve the operating voltage range of the current sampling circuit of switch mosfet element.Particularly can solve the current sample problem that drives control chip and switch mosfet element to close the switch mosfet element of the integrated circuit of envelope.
Accompanying drawing explanation:
Below in conjunction with drawings and Examples, the present invention is further described.
Figure 1A is the structural drawing of the current sampling circuit of conventional MOS FET on-off element.
Figure 1B is specific implementation and the application drawing of the current sampling circuit of conventional MOS FET on-off element.
Fig. 2 A is the structural drawing that increases the current sampling circuit of the modified switch mosfet element of clamper module.
Fig. 2 B is the circuit diagram that increases the first embodiment of the current sampling circuit of the modified switch mosfet element of clamper module.
Fig. 2 C is the circuit diagram that increases the second embodiment of the current sampling circuit of the modified switch mosfet element of clamper module.
Fig. 2 D is the circuit diagram of the 3rd embodiment of the current sampling circuit of the modified switch mosfet element of clamper module.
Fig. 2 E is the circuit diagram that increases the 4th embodiment of the current sampling circuit of the modified switch mosfet element of clamper module.
Embodiment
Below in conjunction with accompanying drawing, content of the present invention is further illustrated.
The problem and the conventional MOS FET on-off element current detection circuit that increase for the current detection circuit power attenuation of solution conventional MOS FET on-off element cannot be applied to the problem that drives control chip and switch mosfet element to close the integrated circuit of envelope; The invention provides the current sampling circuit of modified switch mosfet element, the first end of Direct Sampling switch mosfet element and the voltage difference of the second end, between the first input end of sampling module and the second input end, admissible maximum voltage difference is the withstand voltage between two input ends of sampling module.In the time of high-pressure work, due to the switch mosfet element being operated under switching mode, under switch mosfet element off state, the voltage difference of the first end of switch mosfet element and the second end is very high, can exceed the withstand voltage between sampling module first input end and the second input end, cause sampling module first input end to forming current path between the second input end, thereby the operating voltage range of the current sampling circuit of switch mosfet element is restricted.The present invention increases clamper module in current sample module, utilize the clamper function of the reverse voltage of the diode in clamper module to increase the withstand voltage between sampling module first input end and the second input end, the first input end of blocking-up sampling module forms current path between the second input end, thereby improves the operating voltage range of the current sampling circuit of switch mosfet element.
Simultaneously, the conducting resistance Ron itself existing when on-off element switch mosfet element conductive is as sampling element, in the time of switch mosfet element conductive, the electric current that flows through switch mosfet element can produce voltage difference by conducting resistance Ron between the first end of switch mosfet element and the second end.And Sampling techniques provided by the invention, can Direct Sampling switch mosfet element first end and the voltage difference of the second end, and the conversion output current signal corresponding with the electric current of switch mosfet element.Without sampling element, also remove the power attenuation on sampling element compared to existing technology, particularly can be applied to and drive control chip and switch mosfet element to close the integrated circuit of envelope simultaneously.
As shown in Figure 2 A, the current sampling circuit of switch mosfet element, comprises switch mosfet element 11 and sampling module 13,
Described switch mosfet element 11 is P channel mosfet on-off element, the first end of described on-off element is connected with the first input end of sampling module, and as current input signal end, the second end of described on-off element and the second input end of sampling module are connected, and as switch mosfet element current output signal end, the output terminal of described sampling module is as the sample rate current output signal end of the current sampling circuit of switch mosfet element, and described sampling module comprises clamper module; The first end of described sampling module Direct Sampling switch mosfet element and the voltage difference of the second end, between the first input end of described sampling module and the second input end, admissible maximum voltage difference is the withstand voltage between two input ends of sampling module, described clamper module increases the withstand voltage between sampling module first input end and the second input end, blocking-up forms current path from the first input end end of sampling module to the second input end, improves the operating voltage range of the current sampling circuit of switch mosfet element.
Fig. 2 B is as a kind of circuit diagram of the first embodiment of current sampling circuit of modified switch mosfet element that increases clamper module shown in Fig. 2 A:
Described switch mosfet element 11 is P raceway groove the first metal-oxide-semiconductor M1, the first end of switch mosfet element 11 is source, the second end of switch mosfet element 11 is drain terminal, the source of the first metal-oxide-semiconductor M1 is connected the first input end of sampling module 13 with substrate, and as current input signal end, the drain terminal of the first metal-oxide-semiconductor M1 connects the second input end of sampling module 13 and as switch mosfet element current output signal end, the grid end of the first metal-oxide-semiconductor M1 is inputted grid control signal;
Described sampling module 13 comprises clamper module, the first resistance R 1, second resistance R 2 of the first diode D1, the second diode D2 composition, the 3rd PMOS pipe M3, the 4th PMOS pipe M4, the first constant current source I13, the second constant current source I14, the first resistance R 1 equals the second resistance R 2, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, and the first constant current source I13 equals the second constant current source I14;
The source of the forward end of the first diode D1 and the first metal-oxide-semiconductor M1 is connected with substrate, and as current input signal end, the forward end of the second diode D2 is connected with the drain terminal of the first metal-oxide-semiconductor M1, and as switch mosfet element current output signal end, the backward end of the first diode D1 is connected with one end of the first resistance R 1, the backward end of the second diode D2 is connected with one end of the second resistance R 2, and the other end of the first resistance R 1 is connected with substrate with the source of the 3rd PMOS pipe M3 and as sample rate current output signal end; The other end of the second resistance R 2 is connected with source, the substrate terminal of the 4th PMOS pipe M4, the grid of the drain terminal of the 3rd metal-oxide-semiconductor M3, the grid of the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 is connected with the first constant current source I13, and the drain terminal of the 4th metal-oxide-semiconductor M4 is connected with the second constant current source I14.The grid control signal of the controlled switch mosfet element of sample rate current I15 of exporting by sample rate current output signal end.
Suppose to flow through the electric current I 12 of the first metal-oxide-semiconductor M1 and electric current I 11 approximately equals of current input signal end input, I12 ≈ I11, when the first metal-oxide-semiconductor M1 conducting, its conducting resistance is Ron, both end voltage Vds=Ron × I12=Ron × I11 is leaked in the first metal-oxide-semiconductor M1 source when conducting, when the first metal-oxide-semiconductor M1 conducting:
I13=I14, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, so the source voltage terminal Vs4 of the source voltage terminal Vs3 of the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 meets Vs3=Vs4;
The forward current that flows through the first diode D1, the second diode D2 is respectively the first constant current source I13, the second constant current source I14, establishes its forward voltage drop VF1=VF2;
Voltage VR1=(I13+I15) × R1 in the first resistance R 1, voltage VR2=I14 × R2 in the second resistance R 2, (VR1+VF1) (VR2+VF2)=Vds=Ron × I11 (both end voltage is leaked in the first metal-oxide-semiconductor M1 source), [so (I13+I15) × R1+VF1]-[I14 × R2+VF2]=Ron × I11, I13=I14, R1=R2, VF1=VF2 again, so I15 × R1=I11 × Ron, I15=I11 × Ron/R1.
For Fig. 2 B, suppose that leak in the source of the 3rd metal-oxide-semiconductor M3 in sampling module, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage be V
mAX1the first resistance R 1 and the second resistance R 2 are not subject to withstand voltage impact, the first diode D1 in clamper module and the forward voltage drop VF1=VF2 of the second diode D2, suppose its breakdown reverse voltage VD1=VD2, between the first input end of described sampling module and the second input end, maximum admissible voltage difference is:
V
DSMAX2＝V
MAX1+(I13+I15)×R1+I14×R2+VF1+VD2＝V
MAX1+2×I13×R1+I15×R1+VF1+VD1
According to the requirement of the operating voltage range of current sampling circuit, clamper module can be N the first identical diode D1 second diode D2 composition identical with N, and between the first input end of described sampling module and the second input end, maximum admissible voltage difference is:
V
dSMAX2=V
mAX1+ (I13+I15) × R1+I14 × R2+N × VF1+N × VD2=V
mAX1+ 2 × I13 × R1+I15 × R1+N × VF1+N × VD1 wherein N is equal to, or greater than 1 positive integer.
Fig. 2 C is as a kind of circuit diagram increasing shown in Fig. 2 A in second embodiment of current sampling circuit of modified switch mosfet element of clamper module, for increasing a kind of Transformation Graphs of schematic diagram of current sampling circuit of modified switch mosfet element of clamper module shown in Fig. 2 B, further formed by 3 the first identical diode D1 second diode D2 identical with 3 by clamper module, further improve the withstand voltage between two input ends of sampling module, further improved the operating voltage range of current sampling circuit.
Leak in the source of supposing the 3rd metal-oxide-semiconductor M3 in sampling module, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage be V
mAX1the first resistance R 1 and the second resistance R 2 are not subject to withstand voltage impact, the first diode D1 of clamper module and the forward voltage drop VF1=VF2 of the second diode D2, suppose its breakdown reverse voltage VD1=VD2, between the first input end of described sampling module and the second input end, maximum admissible voltage difference is:
V
DSMAX2＝V
MAX1+(I13+I15)×R1+I14×R2+3×VF1+3×VD2＝V
MAX1+2×I13×R1+I15×R1+3×VF1+3×VD1
Compare with Fig. 2 B, the withstand voltage between two input ends of sampling module has increased V
dSMAX2-V
dSMAX2=2 × VF1+2 × VD1.
Fig. 2 D is as a kind of circuit diagram increasing shown in Fig. 2 A in the 3rd embodiment of current sampling circuit of modified switch mosfet element of clamper module, for increasing a kind of Transformation Graphs of schematic diagram of current sampling circuit of modified switch mosfet element of clamper module shown in Fig. 2 B, change the position that clamper module connects:
Described switch mosfet element 11 is P raceway groove the first metal-oxide-semiconductor M1, the first end of switch mosfet element 11 is source, the second end of switch mosfet element 11 is drain terminal, the source of the first metal-oxide-semiconductor M1 is connected the first input end of sampling module 13 with substrate terminal, and as current input signal end, the drain terminal of the first metal-oxide-semiconductor M1 connects the second input end of sampling module 13 and as switch mosfet element current output signal end I12, the grid end of the first metal-oxide-semiconductor M1 is inputted grid control signal;
Described sampling module 13 comprises clamper module, the first resistance R 1, second resistance R 2 of the first diode D1, the second diode D2 composition, the 3rd PMOS pipe M3, the 4th PMOS pipe M4, the first constant current source I13, the second constant current source I14, the first resistance R 1 equals the second resistance R 2, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, and the first constant current source I13 equals the second constant current source I14;
The source of one end of the first resistance R 1 and the first metal-oxide-semiconductor M1 is connected with substrate terminal, and as current input signal end, one end of the second resistance R 2 is connected with the drain terminal of the first metal-oxide-semiconductor M1 and as switch mosfet element current output signal end, the other end of the first resistance R 1 is connected with the forward end of the first diode D1 and as the sample rate current output signal end of the current sampling circuit of switch mosfet element, the other end of the second resistance R 2 is connected with the forward end of the second diode D2, the backward end of the first diode D1 is connected with substrate with the source of PMOS pipe the 3rd metal-oxide-semiconductor M3, the backward end of the second diode D2 is connected with substrate with the source of the 4th PMOS pipe M4, the drain terminal of the 3rd metal-oxide-semiconductor M3, the 3rd metal-oxide-semiconductor M3, the grid of the 4th metal-oxide-semiconductor M4 is connected with the first constant current source I13, the drain terminal of the 4th metal-oxide-semiconductor M4 is connected with the second constant current source I14.The grid control signal of the controlled switch mosfet element of sample rate current I15 of exporting by sample rate current output signal end.
Fig. 2 E is as a kind of circuit diagram increasing shown in Fig. 2 A in the 4th embodiment of current sampling circuit of modified switch mosfet element of clamper module, for increasing a kind of Transformation Graphs of schematic diagram of current sampling circuit of modified switch mosfet element of clamper module shown in Fig. 2 D, further formed by 3 the first identical diode D1 second diode D2 identical with 3 by clamper module, further improved the operating voltage range of current sampling circuit.
As possibility, described clamper modular structure is further made up of N the first identical diode D1 and N identical the second diode D2, and wherein N is equal to, or greater than 1 positive integer, and the numerical value of its N is determined according to the requirement of circuit design.
In this case, between the first input end of described sampling module and the second input end, maximum admissible voltage difference is V
dSMAX2:
V
dSMAX2=V
mAX1+ (I13+I15) × R1+I14 × R2+N × VF1+N × VD2=V
mAX1+ 2 × I13 × R1+I15 × R1+N × VF1+N × VD1 is wherein:
V
mAX1leak in the source that is the 3rd metal-oxide-semiconductor M3, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage;
I13 is the first constant current source;
I14 is the second constant current source;
I15 is sample rate current;
R1 is the first resistance;
R2 is the second resistance;
VF1 is the first diode D1 forward voltage drop;
VD1 is the first diode D1 breakdown reverse voltage;
The breakdown reverse voltage of VD2 the second diode D2;
N is equal to, or greater than 1 positive integer.
The invention discloses a kind of current sampling circuit of switch mosfet element, and describe the specific embodiment of the present invention and effect with reference to the accompanying drawings.What should be understood that is; above-described embodiment is just to explanation of the present invention; rather than limitation of the present invention; any innovation and creation that do not exceed within the scope of connotation of the present invention; include but not limited to the structure to clamper module samples module; the modification of the connected mode of diode, the change of local structure to circuit and replacement or the modification etc. of other unsubstantialities, within all falling into protection domain of the present invention.
Claims (9)
1. a current sampling circuit for switch mosfet element, is characterized in that, comprises switch mosfet element and sampling module:
Described switch mosfet element is P channel mosfet on-off element, the first end of described on-off element is connected with the first input end of sampling module, and as current input signal end, the second end of described on-off element and the second input end of sampling module are connected, and as switch mosfet element current output signal end, the output terminal of described sampling module is as the sample rate current output signal end of the current sampling circuit of switch mosfet element, the first end of described sampling module Direct Sampling switch mosfet element and the voltage difference of the second end, between the first input end of described sampling module and the second input end, admissible maximum voltage difference is the withstand voltage between two input ends of sampling module,
Described sampling module comprises clamper module, described clamper module increases the withstand voltage between sampling module first input end and the second input end, blocking-up forms current path from the first input end end of sampling module to the second input end, improves the operating voltage range of the current sampling circuit of switch mosfet element.
2. the current sampling circuit of switch mosfet element as claimed in claim 1, is characterized in that,
Described switch mosfet element is P raceway groove the first metal-oxide-semiconductor M1, the first end of switch mosfet element (11) is source, the second end of switch mosfet element is drain terminal, the source of the first metal-oxide-semiconductor M1 is connected the first input end of sampling module with substrate, and as current input signal end, the drain terminal of the first metal-oxide-semiconductor M1 connects the second input end of sampling module and as switch mosfet element current output signal end, the grid end of the first metal-oxide-semiconductor M1 is inputted grid control signal;
Described sampling module comprises clamper module, the first resistance R 1, the second resistance R 2, the three PMOS pipe M3, the 4th PMOS pipe M4, the first constant current source I13, the second constant current source I14 of the second diode D2 composition of the first diode D1, N series connection of N series connection;
The forward end of the first diode D1 and the source of the first metal-oxide-semiconductor M1 of N series connection are connected with substrate, and as current input signal end, the forward end of the second diode D2 of N series connection is connected with the drain terminal of the first metal-oxide-semiconductor M1, and as switch mosfet element current output signal end, the backward end of the first diode D1 of N series connection is connected with one end of the first resistance R 1, the backward end of the second diode D2 of N series connection is connected with one end of the second resistance R 2, the other end of the first resistance R 1 is connected with substrate with the source of the 3rd PMOS pipe M3 and as sample rate current output signal end, the other end of the second resistance R 2 is connected with source, the substrate terminal of the 4th PMOS pipe M4, the grid of the drain terminal of the 3rd metal-oxide-semiconductor M3, the grid of the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 is connected with the first constant current source I13, and the drain terminal of the 4th metal-oxide-semiconductor M4 is connected with the second constant current source I14.
3. the current sampling circuit of switch mosfet element as claimed in claim 2, is characterized in that, between the first input end of described sampling module and the second input end, maximum admissible voltage difference is V
dSMAX2:
V
dSMAX2=V
mAX1+ (I13+I15) × R1+I14 × R2+N × VF1+N × VD2=VMAX1+2 × I13 × R1+I15 × R1+N × VF1+N × VD1 is wherein:
V
mAX1leak in the source that is the 3rd metal-oxide-semiconductor M3, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage;
I13 is the first constant current source;
I14 is the second constant current source;
I15 is sample rate current;
R1 is the first resistance;
R2 is the second resistance;
VF1 is the first diode D1 forward voltage drop;
VD1 is the first diode D1 breakdown reverse voltage;
The breakdown reverse voltage of VD2 the second diode D2;
N is equal to, or greater than 1 positive integer.
4. the current sampling circuit of switch mosfet element as claimed in claim 2 or claim 3, is characterized in that, described N is 1.
5. the current sampling circuit of switch mosfet element as claimed in claim 2 or claim 3, is characterized in that, described N is 3.
6. the current sampling circuit of switch mosfet element as claimed in claim 1, it is characterized in that, described switch mosfet element is P raceway groove the first metal-oxide-semiconductor M1, the first end of switch mosfet element is source, the second end of switch mosfet element is drain terminal, the source of the first metal-oxide-semiconductor M1 is connected the first input end of sampling module with substrate terminal, and as current input signal end, the drain terminal of the first metal-oxide-semiconductor M1 connects the second input end of sampling module and as switch mosfet element current output signal end, the grid end of the first metal-oxide-semiconductor M1 is inputted grid control signal;
Described sampling module comprises clamper module, the first resistance R 1, second resistance R 2 of the second diode D2 composition of the first diode D1, N series connection of N series connection, the 3rd PMOS pipe M3, the 4th PMOS pipe M4, the first constant current source I13, the second constant current source I14, the first resistance R 1 equals the second resistance R 2, the 3rd metal-oxide-semiconductor M3, the 4th metal-oxide-semiconductor M4 are the coupling pipe that breadth length ratio is identical, and the first constant current source I13 equals the second constant current source I14;
The source of one end of the first resistance R 1 and the first metal-oxide-semiconductor M1 is connected with substrate terminal, and as current input signal end, one end of the second resistance R 2 is connected with the drain terminal of the first metal-oxide-semiconductor M1 and as switch mosfet element current output signal end, the other end of the first resistance R 1 is connected with the forward end of the first diode D1 of N series connection and as the sample rate current output signal end of the current sampling circuit of switch mosfet element, the other end of the second resistance R 2 is connected with the forward end of the second diode D2 of N series connection, the backward end of the first diode D1 of N series connection is connected with substrate with the source of PMOS pipe the 3rd metal-oxide-semiconductor M3, the backward end of the second diode D2 of N series connection is connected with substrate with the source of the 4th PMOS pipe M4, the drain terminal of the 3rd metal-oxide-semiconductor M3, the 3rd metal-oxide-semiconductor M3, the grid of the 4th metal-oxide-semiconductor M4 is connected with the first constant current source I13, the drain terminal of the 4th metal-oxide-semiconductor M4 is connected with the second constant current source I14.
7. the current sampling circuit of switch mosfet element as claimed in claim 6, is characterized in that, between the first input end of described sampling module and the second input end, maximum admissible voltage difference is V
dSMAX2:
V
dSMAX2=V
mAX1+ (I13+I15) × R1+I14 × R2+N × VF1+N × VD2=V
mAX1+ 2 × I13 × R1+I15 × R1+N × VF1+N × VD1 is wherein:
V
mAX1leak in the source that is the 3rd metal-oxide-semiconductor M3, substrate terminal, and the source of the 4th metal-oxide-semiconductor M4 leak, can bear between substrate terminal withstand voltage;
I13 is the first constant current source;
I14 is the second constant current source;
I15 is sample rate current;
R1 is the first resistance;
R2 is the second resistance;
VF1 is the first diode D1 forward voltage drop;
VD1 is the first diode D1 breakdown reverse voltage;
The breakdown reverse voltage of VD2 the second diode D2;
N is equal to, or greater than 1 positive integer.
8. the current sampling circuit of the switch mosfet element as described in claim 6 or 7, is characterized in that, described N is 1.
9. the current sampling circuit of the switch mosfet element as described in claim 6 or 7, is characterized in that, described N is 3.
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| CN104155498A (en) * | 2013-05-13 | 2014-11-19 | 苏州工业园区新宏博通讯科技有限公司 | High-voltage hot-swap sampling circuit |
| CN104218929A (en) * | 2013-05-30 | 2014-12-17 | 快捷半导体(苏州)有限公司 | True reverse current blocking circuit, true reverse current blocking method, load switch and portable device |
| CN104764924B (en) * | 2015-03-26 | 2018-01-09 | 深圳市英特源电子有限公司 | High-voltage MOSFET current sampling circuit |
| CN106443128B (en) * | 2016-09-23 | 2019-06-18 | 中国电子科技集团公司第四十一研究所 | A kind of femto-ampere grade low current signal measuring circuit |
| CN106950414B (en) * | 2017-02-24 | 2020-11-17 | 深圳陆巡科技有限公司 | MOS tube current sampling circuit and push-pull circuit |
| CN111426928B (en) * | 2018-12-24 | 2021-08-20 | 东南大学 | Dynamic resistance test circuit for gallium nitride device |
| CN109696578B (en) * | 2019-01-22 | 2020-10-27 | 东莞市长工微电子有限公司 | Current detection circuit and method |
| CN110244095B (en) * | 2019-07-19 | 2021-03-19 | 电子科技大学 | High-speed current sampling circuit with ultralow power consumption |
| CN112782635B (en) * | 2021-01-07 | 2023-05-26 | 广东省肇庆市质量计量监督检测所 | Winding wire breakdown voltage tester calibrating device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101629973A (en) * | 2009-06-09 | 2010-01-20 | 中国人民解放军国防科学技术大学 | High-precision current sampling circuit without operational amplifier for low voltage power supply |
| CN102156211A (en) * | 2010-12-21 | 2011-08-17 | 成都成电硅海科技股份有限公司 | Full-CMOS (complementary metal-oxide-semiconductor transistor) accurate current sampling circuit |
| CN202383186U (en) * | 2011-11-30 | 2012-08-15 | 杭州士兰微电子股份有限公司 | Current sampling circuit of MOSFET switch component |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4247973B2 (en) * | 2003-07-11 | 2009-04-02 | 株式会社ミツトヨ | Current measurement circuit |
-
2011
- 2011-11-30 CN CN201110391321.5A patent/CN102495265B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101629973A (en) * | 2009-06-09 | 2010-01-20 | 中国人民解放军国防科学技术大学 | High-precision current sampling circuit without operational amplifier for low voltage power supply |
| CN102156211A (en) * | 2010-12-21 | 2011-08-17 | 成都成电硅海科技股份有限公司 | Full-CMOS (complementary metal-oxide-semiconductor transistor) accurate current sampling circuit |
| CN202383186U (en) * | 2011-11-30 | 2012-08-15 | 杭州士兰微电子股份有限公司 | Current sampling circuit of MOSFET switch component |
Non-Patent Citations (1)
| Title |
|---|
| JP特开2005-31032A 2005.02.03 |
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