CN112684238A - Switching power tube load current real-time monitoring circuit and monitoring system - Google Patents
Switching power tube load current real-time monitoring circuit and monitoring system Download PDFInfo
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Abstract
The invention discloses a real-time monitoring circuit and a monitoring system for load current of a switching power tube. The system comprises a digital power amplifier driving circuit, a half-bridge MOSFET circuit and a sampling output circuit, wherein the digital power amplifier driving circuit is connected with an audio signal and modulates the input audio signal; the half-bridge MOSFET circuit converts a small-signal pulse square wave signal into a high-voltage pulse square wave signal with low output impedance to realize high-power output; the high-voltage pulse square wave signal is reduced into a high-voltage audio signal through a low-pass filter so as to realize high-power sound amplification; the sampling output circuit adopts the monitoring circuit. The invention has reasonable structure and low cost, and monitors the working current of the switching power tube in real time.
Description
Technical Field
The invention relates to the technical field of audio power amplifier electronics, in particular to a switching power tube load current real-time monitoring circuit and a monitoring system.
Background
Due to the uncertainty of the digital power amplifier load, in order to protect the digital power amplifier in a safe working range, the working current of the digital power amplifier needs to be detected and protected when the digital power amplifier is in overcurrent. The protection mode is various, and the mute power amplifier, the disconnection output, the power supply shutdown and the like can play a good role. But the premise is to establish accurate, rapid current sensing.
The detection means currently being used by designers include a resistance sampling method, a current transformer method, and the like. The resistance sampling method needs to connect sampling resistors in series to an output circuit, power consumption can be generated as long as signals are output, and when the current is too large, heat accumulation is also a potential safety hazard point in a product; if too small a resistance is used, the accuracy of the later stage is reduced, and the contradiction and the response problem of the later stage sampling circuit are often pain points of designers. The current mutual inductance method measures current by using electromagnetic inductance, only can measure line alternating current, the rear end can reach a directly usable signal only through special processing, and the current transformer is large in size and high in cost. In addition, the current value of the final output signal is detected in the above modes, and the current flowing through the switching power tube in real time is not directly reflected. When the digital power amplifier does not output signals, the current of the switching power tube is not zero, but linear current related to power supply voltage and filter inductance is generated, so that the current of the switching power tube is not directly monitored and protected in the above mode, and once the saturation inductance of the inductance is rapidly reduced, the current of the switching power tube rapidly rises, and overcurrent cannot be monitored and protected. And the direct connection fault risk of the digital power amplifier switch power tube cannot be guaranteed.
In summary, the existing load current detection methods (resistance sampling method, current mutual inductance method, etc.) of the switching power tube have high cost, large volume and poor precision, and cannot directly reflect the real-time working current of the power tube.
Disclosure of Invention
The invention aims to solve the technical problems that the existing load current detection modes (a resistance sampling method, a current mutual inductance method and the like) of a switching power tube have high cost, large volume and poor precision, and can not directly reflect the real-time working current of the switching power tube, and aims to provide a real-time load current monitoring circuit and a monitoring system of the switching power tube.
The invention is realized by the following technical scheme:
the monitoring circuit comprises a sampling bias circuit and a signal output circuit, wherein the sampling bias circuit is connected with the signal output circuit, and the monitoring circuit is used as the sampling output circuit of the switching power tube to realize the real-time detection of the load current of the switching power tube.
At present, in the existing switching power load current detection mode (a resistance sampling method, a current mutual inductance method and the like), a sampling resistor needs to be connected in series to an output loop in the resistance sampling method, power consumption can be generated as long as a signal is output, and when the current is too large, heat accumulation is also a potential safety hazard point in a product; if too small a resistance is used, the accuracy of the later stage is reduced, and the contradiction and the response problem of the later stage sampling circuit are often pain points of designers. The current mutual inductance method measures current by using electromagnetic inductance, only can measure line alternating current, the rear end can reach a directly usable signal only through special processing, and the current transformer is large in size and high in cost. In addition, the current value of the final output signal is detected in the above modes, and the current flowing through the switching power tube in real time is not directly reflected. When the digital power amplifier does not output signals, the current of the switching power tube is not zero, but linear current related to power supply voltage and filter inductance is generated, so that the current of the switching power tube is not directly monitored and protected in the above mode, and once the saturation inductance of the inductance is rapidly reduced, the current of the switching power tube rapidly rises, and overcurrent cannot be monitored and protected. And the direct connection fault risk of the digital power amplifier switch power tube cannot be guaranteed. In summary, the existing detection methods (resistance sampling method, current mutual inductance method, etc.) for the current of the switching power load have high cost, large volume and poor precision, and cannot directly represent the real-time working current of the power tube.
The invention designs a switching power tube load current real-time monitoring circuit, which comprises a sampling bias circuit and a signal output circuit, wherein the sampling bias circuit is connected with the signal output circuit, and the monitoring circuit is used as a sampling output circuit of a switching power tube to realize the real-time detection of the load current of the switching power tube; the invention has simple and reasonable structure, low cost, simplicity and clarity, monitors the working current of the switching power tube in real time, and can obtain the actual output current after the processing of the filter.
As a further preferable scheme, the sampling bias circuit comprises a bias pull-up resistor R1 and a bias unidirectional diode D1, and the signal output circuit comprises an amplifying transistor Q5, a base resistor Rb, a collector resistor Rc and an emitter resistor Re, wherein:
the positive electrode of the bias unidirectional diode D1 is connected with a base resistor Rb, the base resistor Rb is connected with the base electrode of the amplifying triode Q5, the collector electrode of the amplifying triode Q5 is connected with a collector resistor Rc, and the emitter electrode of the amplifying triode Q5 is connected with an emitter resistor Re; the negative electrode of the bias unidirectional diode D1 is connected with a switching power tube circuit; the collector resistance Rc is grounded;
one end of the bias pull-up resistor R1 is connected with the common end of the bias unidirectional diode D1 and the base resistor Rb, and the other end is connected with the switch power tube circuit.
Preferably, the amplifying transistor Q5 is an NPN transistor.
Preferably, the voltage on the collector resistor Rc is used as the output voltage of the monitoring circuit, so as to obtain a voltage output of-5V to 0V for the subsequent sampling of the switching power tube.
On the other hand, the invention also provides a real-time monitoring system for the load current of the switching power tube, which comprises a digital power amplifier driving circuit, a half-bridge MOSFET circuit and a sampling output circuit, wherein the digital power amplifier driving circuit is connected with the half-bridge MOSFET circuit;
the digital power amplifier driving circuit is connected with an audio signal and transmits the signal after modulation processing to the half-bridge MOSFET circuit; the half-bridge MOSFET circuit converts a small-signal pulse square wave signal into a high-voltage pulse square wave signal with low output impedance to realize high-power output; the high-voltage pulse square wave signal is reduced into a high-voltage audio signal through a low-pass filter so as to realize high-power sound amplification;
the sampling output circuit adopts the switching power tube load current real-time monitoring circuit.
As a further preferable scheme, the digital power amplifier driving circuit comprises a PWM modulator and a triode totem circuit, the PWM modulator is connected with the triode totem circuit, the PWM modulator is connected with an audio signal, modulates the connected audio signal into pulse square wave signals with different duty ratios, and outputs the pulse square wave signals through push-pull of the triode totem circuit.
As a further preferable scheme, the triode totem circuit comprises a complementary triode Q1 and a triode Q2, wherein the base of the triode Q1 is connected with the base of the triode Q2, the collector of the triode Q1 is connected with the positive electrode (VDD) of the driving power supply voltage, the emitter of the triode Q1 is connected with the emitter of the triode Q2, and the collector of the triode Q2 is connected with the negative electrode (VEE) of the driving power supply voltage; the emitter of the transistor Q1 and the common terminal of the emitter of the transistor Q2 are connected to the half-bridge MOSFET circuit.
As a further preferable scheme, the half-bridge MOSFET circuit includes a MOS transistor Q3 and a MOS transistor Q4, a drain of the transistor Q1 is connected to a positive electrode (VCC) of a supply voltage, a source of the transistor Q1 is connected to a source of the transistor Q2, a drain of the transistor Q2 is connected to a negative electrode (VEE) of the supply voltage, and a gate of the transistor Q2 is connected to an output terminal of the digital power amplifier driving circuit through a resistor R2;
the source of the transistor Q1 and the common terminal of the source of the transistor Q2 are connected to the real-time monitoring circuit of the load current of the switching power tube (i.e. the common terminal of the source of the transistor Q1 and the source of the transistor Q2 is connected to the negative terminal of the biased unidirectional diode D1).
As a further preferable scheme, the low-pass filter LC further comprises an inductor L1 and a capacitor C1; one end of the inductor L1 is connected with the common end of the MOS tube Q3 and the MOS tube Q4, and the other end of the inductor L1 is connected with a voltage output end; the common end of the inductor L1 and the voltage output end is connected with one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
Preferably, the MOS transistors Q3 and Q4 both use N-channel MOSFETs.
Compared with the prior art, the invention has the following advantages and beneficial effects:
1. the invention utilizes the driving voltage to detect the current in real time, and the detection circuit can output an effective voltage value only when the power switch tube is conducted.
2. The invention utilizes the self-on resistance characteristic of the MOSFET to obtain the current value passing through the MOSFET in real time.
3. The current detected by the invention is not only the current on the digital power amplifier load, but also the current actually flowing through the power switch tube at any time when the power switch tube is switched on (including the current flowing through the switch tube when the digital power amplifier is in idle load).
4. The invention designs a real-time monitoring circuit for the load current of a switching power tube, which comprises a sampling bias circuit and a signal output circuit, wherein the sampling bias circuit is connected with the signal output circuit, and the monitoring circuit is used as the sampling output circuit of the switching power tube to realize the real-time detection of the load current of the switching power tube; the invention has simple and reasonable structure, low cost, simplicity and clarity, monitors the working current of the switching power tube in real time, and can obtain the actual output current after the processing of the filter.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:
fig. 1 is a circuit diagram of a switching power transistor load current real-time monitoring circuit and a monitoring system according to the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that: it is not necessary to employ these specific details to practice the present invention. In other instances, well-known structures, circuits, materials, or methods have not been described in detail so as not to obscure the present invention.
Throughout the specification, reference to "one embodiment," "an embodiment," "one example," or "an example" means: the particular features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment of the invention. Thus, the appearances of the phrases "one embodiment," "an embodiment," "one example" or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combination and/or sub-combination in one or more embodiments or examples. Further, those of ordinary skill in the art will appreciate that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
In the description of the present invention, the terms "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "upper", "lower", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore, should not be construed as limiting the scope of the present invention.
Examples
As shown in fig. 1, the monitoring circuit for the load current of the switching power tube in real time according to the present invention includes a sampling bias circuit and a signal output circuit, the sampling bias circuit is connected to the signal output circuit, and the monitoring circuit is used as the sampling output circuit of the switching power tube to achieve real-time detection of the load current of the switching power tube.
The invention relates to a real-time monitoring circuit for load current of a switching power tube, which is a circuit for determining the magnitude of the current passing through a power switching tube MOSFET through the characteristics of the power switching tube MOSFET.
Specifically, the sampling bias circuit comprises a bias pull-up resistor R1 and a bias unidirectional diode D1, and the signal output circuit comprises an amplifying triode Q5, a base resistor Rb, a collector resistor Rc and an emitter resistor Re, wherein:
the positive electrode of the bias unidirectional diode D1 is connected with a base resistor Rb, the base resistor Rb is connected with the base electrode of the amplifying triode Q5, the collector electrode of the amplifying triode Q5 is connected with a collector resistor Rc, and the emitter electrode of the amplifying triode Q5 is connected with an emitter resistor Re; the negative electrode of the bias unidirectional diode D1 is connected with a switching power tube circuit; the collector resistance Rc is grounded;
one end of the bias pull-up resistor R1 is connected with the common end of the bias unidirectional diode D1 and the base resistor Rb, and the other end is connected with the switch power tube circuit.
Specifically, the amplifying transistor Q5 is an NPN-type transistor.
Specifically, the voltage on the collector resistor Rc is used as the output voltage of the monitoring circuit, and a voltage output of-5V to 0V is obtained for the later stage sampling of the switching power tube.
The invention designs a switching power tube load current real-time monitoring circuit, which comprises a sampling bias circuit and a signal output circuit, wherein the sampling bias circuit is connected with the signal output circuit, and the monitoring circuit is used as a sampling output circuit of a switching power tube to realize the real-time detection of the load current of the switching power tube; the invention has simple and reasonable structure, low cost, simplicity and clarity, monitors the working current of the switching power tube in real time, and can obtain the actual output current after the processing of the filter.
Example 2
As shown in fig. 1, the present embodiment is different from embodiment 1 in that the present embodiment provides a real-time monitoring system for load current of a switching power tube, and the system includes a digital power amplifier driving circuit, a half-bridge MOSFET circuit, and a sampling output circuit, where the digital power amplifier driving circuit is connected to the half-bridge MOSFET circuit, the half-bridge MOSFET circuit is connected to the sampling output circuit, and the sampling output circuit is further connected to a common terminal of the digital power amplifier driving circuit and the half-bridge MOSFET circuit;
the digital power amplifier driving circuit is connected with an audio signal and transmits the signal after modulation processing to the half-bridge MOSFET circuit; the half-bridge MOSFET circuit converts a small-signal pulse square wave signal into a high-voltage pulse square wave signal with low output impedance to realize high-power output; the high-voltage pulse square wave signal is reduced into a high-voltage audio signal through a low-pass filter so as to realize high-power sound amplification;
the sampling output circuit adopts the switching power tube load current real-time monitoring circuit.
Specifically, the digital power amplifier driving circuit comprises a PWM modulator and a triode totem circuit, wherein the PWM modulator is connected with the triode totem circuit, and is connected with an audio signal, modulates the connected audio signal into pulse square signals with different duty ratios, and outputs the pulse square signals in a push-pull mode through the triode totem circuit.
Specifically, the triode totem circuit comprises a triode Q1 and a triode Q2 which are complementary, wherein the base electrode of the triode Q1 is connected with the base electrode of the triode Q2, the collector electrode of the triode Q1 is connected with the positive electrode (VDD) of the driving power supply voltage, the emitter electrode of the triode Q1 is connected with the emitter electrode of the triode Q2, and the collector electrode of the triode Q2 is connected with the negative electrode (VEE) of the driving power supply voltage; the emitter of the transistor Q1 and the common terminal of the emitter of the transistor Q2 are connected to the half-bridge MOSFET circuit.
Specifically, the half-bridge MOSFET circuit comprises a MOS transistor Q3 and a MOS transistor Q4, a drain of the triode Q1 is connected to a positive electrode (VCC) of a power supply voltage, a source of the triode Q1 is connected to a source of the triode Q2, a drain of the triode Q2 is connected to a negative electrode (VEE) of the power supply voltage, and a gate of the triode Q2 is connected to an output end of the digital power amplifier driving circuit through a resistor R2;
the source of the transistor Q1 and the common terminal of the source of the transistor Q2 are connected to the real-time monitoring circuit of the load current of the switching power tube (i.e. the common terminal of the source of the transistor Q1 and the source of the transistor Q2 is connected to the negative terminal of the biased unidirectional diode D1).
In particular, a low-pass filter LC is also included, which comprises an inductance L1 and a capacitance C1; one end of the inductor L1 is connected with the common end of the MOS tube Q3 and the MOS tube Q4, and the other end of the inductor L1 is connected with a voltage output end; the common end of the inductor L1 and the voltage output end is connected with one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
Specifically, the MOS transistor Q3 and the MOS transistor Q4 both use N-channel MOSFETs.
When in implementation: as shown in fig. 1, the whole system comprises a digital power amplifier driving circuit, a half-bridge MOSFET circuit and a sampling output circuit; the digital power amplifier driving circuit modulates an audio signal into pulse square wave signals (a PWM (pulse-width modulation) modulator in figure 1) with different duty ratios, and then outputs the pulse square wave signals in a push-pull mode by using a triode totem circuit (Q1 and Q2 complementary triodes in figure 1); the half-bridge MOSFET circuit converts small-signal pulse square wave signals (Q3 and Q4N channel MOSFET half bridges in figure 1) into high-voltage pulse square wave signals with low output impedance so as to realize high-power output; finally, the high-voltage pulse square wave signal is restored into a high-voltage audio signal through an LC low-pass filter, so that high-power sound amplification is realized.
The invention relates to a real-time monitoring circuit for load current of a switching power tube, which consists of a sampling output circuit in a dotted line frame in figure 1; the sampling output circuit comprises a sampling bias circuit and a signal output circuit;
the sampling bias circuit comprises a bias pull-up resistor R1 and a bias unidirectional diode D1, wherein the bias pull-up resistor R1, the bias unidirectional diode D1 and a MOS transistor Q4 (namely a power switch transistor Q4) jointly form a sampling loop, namely a resistor Rds (on) when R1, D1 and Q4 are switched on, the loop can work only when the driving circuit outputs a high level (is switched off when the driving circuit outputs a low level), namely the MOS transistor Q4 (namely the power switch transistor Q4) can work when the driving circuit is switched on, and the real-time performance and the stability of the sampling bias circuit are further embodied. When the driving signal drives the output high driving Q4, the sampling loop A-B-C-D is formed, the on-resistance tube voltage drop of MOS transistor Q4 and the biasing diode D1 clamp the voltage at point B in FIG. 1, and the voltage VB at point B varies with the current Id flowing through MOS transistor Q4 (i.e., power switch Q4).
The signal output circuit is a common emitter triode amplifying circuit and comprises an amplifying triode Q5, a base resistor Rb, a collector resistor Rc and an emitter resistor Re; in fig. 1, a sampling voltage VB at a point B is based on a VEE power rail, and a digital power amplifier generally has VEE up to-100V or even higher absolute value voltage and is difficult to be used by a post-stage circuit, so that the amplifying circuit not only has the functions of amplifying voltage and current, but also has the function of level reference lifting; in fig. 1, the triode Q5 realizes the function of current amplification, and under the action of the base resistor Rb and the emitter resistor Re, the base current IRb output to the triode Q5 by the sampling bias circuit can be as small as possible, so that the influence on the driving of the power switch tube is reduced; the collector resistance Rc converts the current amplified by the triode Q5 into voltage, one end of the collector resistance Rc is grounded (0V), so the voltage on the collector resistance Rc is the final output voltage of the invention, namely the load current I-OUT is converted into the output value of the voltage, the voltage is a negative voltage taking the level of 0V as the reference, and the voltage can be set to obtain the voltage output of-5V to 0V through strict value taking, thereby being convenient for later-stage sampling.
Analyzing the working principle:
a sampling bias circuit: setting the driving power supply voltage as VDD; biasing the forward voltage of the unidirectional diode D1 to Vd;
when the triode Q1 (as a driving tube) is conducted, the voltage of the point A is VDD, the MOS tube Q4 (namely the power switch tube Q4) normally works, and the sampling bias circuit works; the voltage at point a applies source energy to the bias sampling loop through the bias pull-up resistor R1, making the loop conduct in the forward direction. The point B will generate a voltage related to the on-resistance rds (on) of the MOS transistor Q4 (i.e., the power switch Q4) and the load current.
Neglecting the influence of the base current IRb of the signal output circuit transistor Q5 on the sampling loop, wherein the voltage VB at the point B is rds (on) Id + Vd;
a signal output circuit: setting the direct-current amplification factor of the triode Q5 as beta and the starting voltage of a B-E pole as Vbe;
at this time, the voltage at the point B is directly output by the transistor Q5 and obtained by the common emitter amplifying circuit,
a transistor Q5 is input into the loop,
VB＝IRb*Rb+Vbe+(β+1)*IRb*Re；
the voltage is output at the collector of transistor Q5,
VP＝-β*IRb*Rc；
finally, an output voltage related to the load current is obtained,
therefore, an expression of VP and Id is shown, the real-time load current Id required by the invention is shown through VP, and the circuit is simple and reliable.
The invention utilizes the driving voltage to detect the current in real time, and the detection circuit can output an effective voltage value only when the power switch tube is conducted; the invention obtains the current value passing through the MOSFET in real time by utilizing the self-on resistance characteristic of the MOSFET; the current detected by the invention is not only the current on the digital power amplifier load, but also the current actually flowing through the power switch tube at any time when the power switch tube is turned on (including the current flowing through the switch tube when the digital power amplifier is in idle load).
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. The monitoring circuit is characterized by comprising a sampling bias circuit and a signal output circuit, wherein the sampling bias circuit is connected with the signal output circuit, and the monitoring circuit is used as the sampling output circuit of the switching power tube to realize the real-time detection of the load current of the switching power tube.
2. The real-time load current monitoring circuit of the switching power tube as claimed in claim 1, wherein the sampling bias circuit comprises a bias pull-up resistor R1 and a bias unidirectional diode D1, and the signal output circuit comprises an amplifying transistor Q5, a base resistor Rb, a collector resistor Rc and an emitter resistor Re, wherein:
the positive electrode of the bias unidirectional diode D1 is connected with a base resistor Rb, the base resistor Rb is connected with the base electrode of the amplifying triode Q5, the collector electrode of the amplifying triode Q5 is connected with a collector resistor Rc, and the emitter electrode of the amplifying triode Q5 is connected with an emitter resistor Re; the negative electrode of the bias unidirectional diode D1 is connected with a switching power tube circuit; the collector resistance Rc is grounded;
one end of the bias pull-up resistor R1 is connected with the common end of the bias unidirectional diode D1 and the base resistor Rb, and the other end is connected with the switch power tube circuit.
3. The circuit for real-time monitoring of the load current of the switching power tube as claimed in claim 2, wherein the amplifying transistor Q5 is an NPN transistor.
4. The real-time load current monitoring circuit of a switching power tube according to claim 2, wherein the voltage at the collector resistance Rc is used as the output voltage of the monitoring circuit, and a voltage output of-5V to 0V is obtained for the subsequent sampling of the switching power tube.
5. A real-time monitoring system for load current of a switching power tube is characterized by comprising a digital power amplifier driving circuit, a half-bridge MOSFET circuit and a sampling output circuit, wherein the digital power amplifier driving circuit is connected with the half-bridge MOSFET circuit;
the digital power amplifier driving circuit is connected with an audio signal and transmits the signal after modulation processing to the half-bridge MOSFET circuit; the half-bridge MOSFET circuit converts a small-signal pulse square wave signal into a high-voltage pulse square wave signal with low output impedance to realize high-power output; the high-voltage pulse square wave signal is reduced into a high-voltage audio signal through a low-pass filter so as to realize high-power sound amplification;
the sampling output circuit adopts a switching power tube load current real-time monitoring circuit as claimed in any one of claims 1 to 4.
6. The system according to claim 5, wherein the digital power amplifier driving circuit comprises a PWM modulator and a triode totem circuit, the PWM modulator is connected with the triode totem circuit, the PWM modulator is connected with an audio signal, modulates the connected audio signal into pulse square signals with different duty ratios, and outputs the pulse square signals through push-pull of the triode totem circuit.
7. The switching power transistor load current real-time monitoring system according to claim 6, wherein the transistor totem circuit comprises a complementary transistor Q1 and a transistor Q2, a base of the transistor Q1 is connected to a base of the transistor Q2, a collector of the transistor Q1 is connected to a positive pole of the driving power voltage, an emitter of the transistor Q1 is connected to an emitter of the transistor Q2, and a collector of the transistor Q2 is connected to a negative pole of the driving power voltage; the emitter of the transistor Q1 and the common terminal of the emitter of the transistor Q2 are connected to the half-bridge MOSFET circuit.
8. The switching power tube load current real-time monitoring system according to claim 5, wherein the half-bridge MOSFET circuit comprises a MOS tube Q3 and a MOS tube Q4, a drain of the transistor Q1 is connected to a positive pole of a supply voltage, a source of the transistor Q1 is connected to a source of a transistor Q2, a drain of the transistor Q2 is connected to a negative pole of the supply voltage, and a gate of the transistor Q2 is connected to the output terminal of the digital power amplifier driving circuit through a resistor R2;
the source electrode of the triode Q1 and the common end of the source electrode of the triode Q2 are connected with the sampling output circuit.
9. The switching power tube load current real-time monitoring system according to claim 8, further comprising a low-pass filter LC, wherein the low-pass filter LC comprises an inductor L1 and a capacitor C1; one end of the inductor L1 is connected with the common end of the MOS tube Q3 and the MOS tube Q4, and the other end of the inductor L1 is connected with a voltage output end; the common end of the inductor L1 and the voltage output end is connected with one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
10. The system according to claim 8, wherein each of the MOS transistors Q3 and Q4 is an N-channel MOSFET.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113791266A (en) * | 2021-10-09 | 2021-12-14 | 富芯微电子有限公司 | MOSFET current detection device |
| CN113984244A (en) * | 2021-10-22 | 2022-01-28 | 臻驱科技（上海）有限公司 | Protection circuit of motor temperature sampling interface, motor temperature sampling module and electric vehicle |
| CN114487554A (en) * | 2022-01-28 | 2022-05-13 | 西北核技术研究所 | IV measuring method of pulse power amplifier |
Citations (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5054047A (en) * | 1988-01-06 | 1991-10-01 | Jupiter Toy Company | Circuits responsive to and controlling charged particles |
| JPH0946145A (en) * | 1995-07-28 | 1997-02-14 | Matsushita Electric Ind Co Ltd | Class d power amplifier |
| US6313690B1 (en) * | 1999-02-14 | 2001-11-06 | Yazaki Corporation | Semiconductor switching device with leakage current detecting junction |
| JP2003110378A (en) * | 2001-09-28 | 2003-04-11 | Sharp Corp | Constant-current circuit and constant-voltage circuit using the same |
| AU2006324377A1 (en) * | 2005-12-12 | 2007-06-21 | Clipsal Australia Pty Ltd | Load detector for a dimmer |
| CN201312286Y (en) * | 2008-11-27 | 2009-09-16 | 比亚迪股份有限公司 | D-type audio-frequency power amplifier and overcurrent output protecting circuit thereof |
| US20100026390A1 (en) * | 2008-08-01 | 2010-02-04 | Haruhiko Koizumi | Detector circuit and system for a wireless communication |
| CN101821852A (en) * | 2007-08-08 | 2010-09-01 | 先进模拟科技公司 | The cascode current sensor that is used for discrete power semiconductor devices |
| CN102594263A (en) * | 2012-02-13 | 2012-07-18 | 金海辉 | Simple and high-efficiency super class-A power amplifier |
| CN102684652A (en) * | 2012-06-04 | 2012-09-19 | 浙江榆阳电子有限公司 | Synchronous pulse control circuit for preventing faults of microprogrammed control unit (MCU) or driving integrated circuit (IC) |
| CN203278779U (en) * | 2013-05-14 | 2013-11-06 | 美的集团股份有限公司 | Drive circuit of switching element |
| CN203406774U (en) * | 2013-04-25 | 2014-01-22 | 薛涛 | Large-power MOSFET negative-voltage drive circuit |
| CN103560716A (en) * | 2013-11-15 | 2014-02-05 | 科博达技术有限公司 | Auxiliary fuel pump electric control system and method for achieving soft starting of system |
| CN104639056A (en) * | 2015-01-12 | 2015-05-20 | 宁波明科机电有限公司 | Rapid protecting circuit for power amplifier |
| CN104764924A (en) * | 2015-03-26 | 2015-07-08 | 深圳市英特源电子有限公司 | High-voltage MOSFET current sampling circuit |
| CN106950414A (en) * | 2017-02-24 | 2017-07-14 | 深圳陆巡科技有限公司 | Metal-oxide-semiconductor current sampling circuit and push-pull circuit |
| CN107124148A (en) * | 2017-06-08 | 2017-09-01 | 尚睿微电子（上海）有限公司 | One kind control circuit, biasing circuit and control method |
| CN207442434U (en) * | 2017-10-13 | 2018-06-01 | 高创传动科技开发（深圳）有限公司 | Overcurrent detection circuit and AGV motor driver |
| WO2018126555A1 (en) * | 2017-01-04 | 2018-07-12 | 广东百事泰电子商务股份有限公司 | Smart sine wave voltage conversion circuit based on pfc, full bridge and half bridge |
| JP2018163497A (en) * | 2017-03-24 | 2018-10-18 | エイブリック株式会社 | Semiconductor circuit |
| CN110995168A (en) * | 2019-11-22 | 2020-04-10 | 珠海格力电器股份有限公司 | Envelope modulator and method applied to power amplifier |
| CN210641059U (en) * | 2019-10-22 | 2020-05-29 | 四川湖山电器股份有限公司 | Power-down mute circuit for audio power amplifier |
| CN111431395A (en) * | 2020-03-13 | 2020-07-17 | 大连理工大学 | Switch ringing suppression circuit based on gate driver and control method thereof |
| CN211063592U (en) * | 2020-02-10 | 2020-07-21 | 四川华讯新科科技有限公司 | Radio frequency switch biasing circuit for SoC chip |
| CN111435144A (en) * | 2018-12-26 | 2020-07-21 | 株式会社东芝 | Current detection circuit |
| CN111614281A (en) * | 2020-05-09 | 2020-09-01 | 上海紫通信息科技有限公司 | Novel low-voltage high-frequency band inverter circuit |
| CN111864713A (en) * | 2020-08-18 | 2020-10-30 | 四川湖山电器股份有限公司 | Overvoltage protection device for high pitch loudspeaker |
-
2021
- 2021-01-08 CN CN202110023132.6A patent/CN112684238B/en active Active
Patent Citations (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5054047A (en) * | 1988-01-06 | 1991-10-01 | Jupiter Toy Company | Circuits responsive to and controlling charged particles |
| JPH0946145A (en) * | 1995-07-28 | 1997-02-14 | Matsushita Electric Ind Co Ltd | Class d power amplifier |
| US6313690B1 (en) * | 1999-02-14 | 2001-11-06 | Yazaki Corporation | Semiconductor switching device with leakage current detecting junction |
| JP2003110378A (en) * | 2001-09-28 | 2003-04-11 | Sharp Corp | Constant-current circuit and constant-voltage circuit using the same |
| AU2006324377A1 (en) * | 2005-12-12 | 2007-06-21 | Clipsal Australia Pty Ltd | Load detector for a dimmer |
| CN101821852A (en) * | 2007-08-08 | 2010-09-01 | 先进模拟科技公司 | The cascode current sensor that is used for discrete power semiconductor devices |
| US20100026390A1 (en) * | 2008-08-01 | 2010-02-04 | Haruhiko Koizumi | Detector circuit and system for a wireless communication |
| CN201312286Y (en) * | 2008-11-27 | 2009-09-16 | 比亚迪股份有限公司 | D-type audio-frequency power amplifier and overcurrent output protecting circuit thereof |
| CN102594263A (en) * | 2012-02-13 | 2012-07-18 | 金海辉 | Simple and high-efficiency super class-A power amplifier |
| CN102684652A (en) * | 2012-06-04 | 2012-09-19 | 浙江榆阳电子有限公司 | Synchronous pulse control circuit for preventing faults of microprogrammed control unit (MCU) or driving integrated circuit (IC) |
| CN203406774U (en) * | 2013-04-25 | 2014-01-22 | 薛涛 | Large-power MOSFET negative-voltage drive circuit |
| CN203278779U (en) * | 2013-05-14 | 2013-11-06 | 美的集团股份有限公司 | Drive circuit of switching element |
| CN103560716A (en) * | 2013-11-15 | 2014-02-05 | 科博达技术有限公司 | Auxiliary fuel pump electric control system and method for achieving soft starting of system |
| CN104639056A (en) * | 2015-01-12 | 2015-05-20 | 宁波明科机电有限公司 | Rapid protecting circuit for power amplifier |
| CN104764924A (en) * | 2015-03-26 | 2015-07-08 | 深圳市英特源电子有限公司 | High-voltage MOSFET current sampling circuit |
| WO2018126555A1 (en) * | 2017-01-04 | 2018-07-12 | 广东百事泰电子商务股份有限公司 | Smart sine wave voltage conversion circuit based on pfc, full bridge and half bridge |
| CN106950414A (en) * | 2017-02-24 | 2017-07-14 | 深圳陆巡科技有限公司 | Metal-oxide-semiconductor current sampling circuit and push-pull circuit |
| JP2018163497A (en) * | 2017-03-24 | 2018-10-18 | エイブリック株式会社 | Semiconductor circuit |
| CN107124148A (en) * | 2017-06-08 | 2017-09-01 | 尚睿微电子（上海）有限公司 | One kind control circuit, biasing circuit and control method |
| CN207442434U (en) * | 2017-10-13 | 2018-06-01 | 高创传动科技开发（深圳）有限公司 | Overcurrent detection circuit and AGV motor driver |
| CN111435144A (en) * | 2018-12-26 | 2020-07-21 | 株式会社东芝 | Current detection circuit |
| CN210641059U (en) * | 2019-10-22 | 2020-05-29 | 四川湖山电器股份有限公司 | Power-down mute circuit for audio power amplifier |
| CN110995168A (en) * | 2019-11-22 | 2020-04-10 | 珠海格力电器股份有限公司 | Envelope modulator and method applied to power amplifier |
| CN211063592U (en) * | 2020-02-10 | 2020-07-21 | 四川华讯新科科技有限公司 | Radio frequency switch biasing circuit for SoC chip |
| CN111431395A (en) * | 2020-03-13 | 2020-07-17 | 大连理工大学 | Switch ringing suppression circuit based on gate driver and control method thereof |
| CN111614281A (en) * | 2020-05-09 | 2020-09-01 | 上海紫通信息科技有限公司 | Novel low-voltage high-frequency band inverter circuit |
| CN111864713A (en) * | 2020-08-18 | 2020-10-30 | 四川湖山电器股份有限公司 | Overvoltage protection device for high pitch loudspeaker |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113791266A (en) * | 2021-10-09 | 2021-12-14 | 富芯微电子有限公司 | MOSFET current detection device |
| CN113984244A (en) * | 2021-10-22 | 2022-01-28 | 臻驱科技（上海）有限公司 | Protection circuit of motor temperature sampling interface, motor temperature sampling module and electric vehicle |
| CN113984244B (en) * | 2021-10-22 | 2023-10-20 | 臻驱科技（上海）有限公司 | Protection circuit of motor temperature sampling interface, motor temperature sampling module and electric vehicle |
| CN114487554A (en) * | 2022-01-28 | 2022-05-13 | 西北核技术研究所 | IV measuring method of pulse power amplifier |
| CN114487554B (en) * | 2022-01-28 | 2024-05-14 | 西北核技术研究所 | IV measuring method of pulse power amplifier |
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