Power amplifier device with fault composite detection function

Abstract

The utility model discloses a power amplifier device with a fault composite detection function, and relates to the technical field of electronics, in particular to the power amplifier device with the fault composite detection function, which comprises a power supply module, a processing module, a power amplifier module and a display module, the power supply module comprises a main power supply circuit used for outputting working voltage and supplying power to the power amplifier module and the display module. The working voltage comprises a first working voltage and a second working voltage; the processing module comprises a signal conversion circuit and an MCU, and the MCU is connected with the signal conversion circuit; a first access end of the signal conversion circuit is connected with a first working voltage; the power amplifier module comprises a power output end and a power amplifier chip, and the power amplifier chip comprises a current detection pin and a first feedback signal output pin; a second working voltage is connected to the current detection pin; a second access end of the signal conversion circuit is connected with the first feedback signal output pin; a user can intuitively judge the fault type of the equipment through the display module connected with the MCU.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, in particular to a power amplifier device with composite fault detection. Background Art

[0002] In the prior art power amplifier devices, although simple current or temperature protection is provided, the protection method is often to directly cut off the power supply. Therefore, when the device fails to work normally, the user cannot intuitively judge the fault type of the device, and cannot directly take corresponding troubleshooting measures. Utility Model Content

[0003] The purpose of the utility model is to avoid the deficiencies in the prior art and to provide a technology capable of performing composite detection on overvoltage, undervoltage, overcurrent and high temperature faults of a power amplifier.

[0004] The purpose of the utility model is achieved through the following technical solutions:

[0005] A power amplifier device with fault composite detection comprises: a power module, a processing module, a power amplifier module and a display module; the power module comprises a main power supply circuit for outputting a working voltage to supply power to the power amplifier module and the display module respectively; the working voltage comprises a first working voltage and a second working voltage; the processing module comprises a signal conversion circuit and an MCU, the MCU is connected to the signal conversion circuit; the first access end of the signal conversion circuit is connected to the first working voltage; the power amplifier module comprises a power output end and a power amplifier chip, the power amplifier chip comprises a current detection pin and a first feedback signal output pin; the current detection pin is connected to the second working voltage; the second access end of the signal conversion circuit is connected to the first feedback signal output pin; the display module is connected to the MCU, and is used to display the detection result.

[0006] Specifically, the signal conversion circuit also includes a first voltage-dividing resistor and a second voltage-dividing resistor; one end of the first voltage-dividing resistor is connected to the first working voltage through the first access end, and the other end is connected to the first detection pin of the MCU and one end of the second voltage-dividing resistor, and the other end of the second voltage-dividing resistor is grounded.

[0007] More specifically, the operating voltage also includes a reference operating voltage; the signal conversion circuit also includes a first transistor; the collector of the first transistor is connected to the first feedback signal output pin through the second access terminal, the emitter is connected to the reference operating voltage, and the base is connected to the second detection pin of the MCU.

[0008] More specifically, the signal conversion circuit further includes a first diode and a second diode; one end of the first diode and the second diode is grounded, and the other end is separately connected to the corresponding first detection pin and the second detection pin respectively.

[0009] In another specific embodiment, the power amplifier module also includes a first MOS tube and a second MOS tube; the gates of the first MOS tube and the second MOS tube are separately connected to the control pins corresponding to the power amplifier chip; the drain of the first MOS tube is connected to the first working voltage, and the source is connected to the power output end; the source of the second MOS tube is connected to the second working voltage, and the drain is connected to the power output end.

[0010] More specifically, the power amplifier module is further provided with a heat sink; the first MOS tube and the second MOS tube are fixedly mounted on the heat sink.

[0011] More specifically, it also includes a temperature detection module, which is connected to the MCU; the temperature detection module includes a thermistor, which is arranged on the radiator.

[0012] More specifically, the temperature detection module also includes a first voltage regulating resistor, a second voltage regulating resistor and a comparator; the reference working voltage is connected to the reverse input terminal of the comparator through the first voltage regulating resistor; the reference working voltage is connected to the positive input terminal of the comparator through the thermistor and the second voltage regulating resistor in turn; the output terminal of the comparator is connected to the third detection pin of the MCU.

[0013] More specifically, the thermistor is a thermistor with a negative temperature coefficient.

[0014] In the above, the power supply module also includes an auxiliary power supply circuit. The main power supply circuit is connected to the input end of the auxiliary power supply circuit to power the auxiliary power supply circuit; the output end of the auxiliary power supply circuit is connected to the MCU to provide a third operating voltage for the MCU.

[0015] The beneficial effects achieved by the utility model are as follows: a power amplifier device with composite fault detection comprises: a power module, a processing module, a power amplifier module and a display module; the power module comprises a main power supply circuit for outputting a working voltage, respectively supplying power to the power amplifier module and the display module; the working voltage comprises a first working voltage and a second working voltage; the processing module comprises a signal conversion circuit and an MCU, and the MCU is connected to the signal conversion circuit; the first access end of the signal conversion circuit is connected to the first working voltage; the power amplifier module comprises a power output end and a power amplifier chip, and the power amplifier chip comprises a current detection pin and a first feedback signal output pin; the current detection pin is connected to the second working voltage; the second access end of the signal conversion circuit is connected to the first feedback signal output pin; the user can intuitively judge the fault type of the device through the display module connected to the MCU. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 It is a schematic block diagram of a power amplifier device with composite fault detection according to an embodiment of the utility model;

[0018] Figure 2 It is a circuit principle schematic diagram of a main power supply circuit of a power amplifier device with a composite fault detection according to an embodiment of the utility model;

[0019] Figure 3 It is a circuit principle schematic diagram of an auxiliary power supply circuit of a power amplifier device with a composite fault detection according to an embodiment of the utility model;

[0020] Figure 4 It is a schematic diagram of the circuit principle of a power amplifier module of a power amplifier device with a composite fault detection according to an embodiment of the utility model;

[0021] Figure 5 It is a schematic diagram of the circuit principle of a processing module of a power amplifier device with a composite fault detection according to an embodiment of the utility model;

[0022] Figure 6 The present invention is a schematic diagram of the circuit principle of a temperature detection module of a power amplifier device with composite fault detection according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the utility model clearer, the following will refer to the drawings in the embodiments of the utility model to clearly and completely describe the technical solution of the utility model through the implementation method. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] Example 1

[0025] One of the implementation methods of the power amplifier device provided with a composite fault detection of the utility model is as follows: Figures 1 to 6 As shown, it includes: a power module, a processing module, a power amplifier module, a temperature detection module and a display module. Among them, the processing module includes a signal conversion circuit and an MCU, and the MCU is connected to the signal conversion circuit; the display module is connected to the MCU and is used to display the detection results.

[0026] The power module includes a circuit for outputting the working voltage, and supplies power to the processing module, the power amplifier module, the temperature detection module and the display module respectively. The power module includes a main power supply circuit and an auxiliary power supply circuit. The main power supply circuit is used to output the first working voltage VCC, the second working voltage VSS, the first reference working voltage +5V and the second reference working voltage -5V. The auxiliary power supply circuit is used to output the third working voltage (MCU VCC).

[0027] In this embodiment, the operating voltage range of the main power supply circuit is: AC180V-260V. The external power supply AC220V is rectified and filtered by rectifier D1, capacitor C1 and capacitor C2, and then the starting voltage is provided to the power chip U1 through resistor R1. Among them, capacitor C9 and capacitor C10 are filter capacitors, which can filter out the high-order harmonic components in the power supply. Capacitor C1 and capacitor C2 form a bridge with switch tube Q1 and switch tube Q2. The diagonal of the bridge is connected to the primary winding of transformer T1. When switch tube Q1 and switch tube Q2 are alternately turned on, energy is transferred from the primary side of transformer T1 to the secondary side. Capacitor C6, diode D5 and diode D7 form a voltage doubler rectifier circuit to provide working voltage for power chip U1. Resistors R3 and R6 are used to divide the third working voltage (MCU VCC in the figure), which is then transmitted to the SD pin of the power chip U1. Capacitor C15 is used as a voltage holding capacitor to prevent voltage mutations. The start-up level of the SD pin of the power chip U1 is between 1.6V and 5.1V. When the voltage at the SD pin is greater than 5.1V, the power chip U1 does not work and there is no voltage output on the secondary side.

[0028] The main power supply circuit is connected to the input end of the auxiliary power supply circuit to supply power to the auxiliary power supply circuit (+MVCC); the output end of the auxiliary power supply circuit is connected to the MCU to provide a third operating voltage to the MCU.

[0029] In this embodiment, the external AC220V power supply is rectified and filtered by the rectifier D1, capacitor C1 and capacitor C2 to obtain a voltage +MVCC; which supplies power to the switching power supply U3; when the switching power supply U3 is working, the diode D10 and capacitor C30 on the secondary side of the transformer T2 rectify and filter to output a third working voltage to provide power for the MCU.

[0030] The power amplifier module is provided with working voltage by the first working voltage VCC and the second working voltage VSS, and the power amplifier chip U2 in the power amplifier module is provided with working voltage by the first reference working voltage +5V and the second reference working voltage -5V. The power amplifier module includes: a power output terminal OUT, a power amplifier chip U2, a first MOS tube Q3 and a second MOS tube Q4; the gates of the first MOS tube Q3 and the second MOS tube Q4 are separately connected to the control pins (HO pin and LO pin) corresponding to the power amplifier chip U2; the drain of the first MOS tube Q3 is connected to the first working voltage VCC, and the source is connected to the power output terminal OUT; the source of the second MOS tube Q4 is connected to the second working voltage VSS, and the drain is connected to the power output terminal OUT. Among them, the power amplifier module is also provided with a heat sink; the first MOS tube Q3 and the second MOS tube Q4 are fixed on the heat sink.

[0031] During operation, after the analog signal IN is input from one end of the resistor R20, it is converted into digital form inside the power amplifier chip U2, and the corresponding PWM waveforms are output from the HO pin and the LO pin respectively, so that the first MOS tube Q3 and the second MOS tube Q4 are turned on in sequence, and then output from the power output terminal OUT after being filtered by the inductor L1 and the capacitor C23.

[0032] The resistor R25, the capacitor C27 and the resistor R26 form a feedback network. The CSD pin (pin 5) is a first feedback signal output pin, and the second reference working voltage -5V is connected to the capacitor C24 through the resistor R21 for reverse charging the capacitor C24.

[0033] The current detection pin OCSET (pin 8) is connected to the second working voltage VSS, and after voltage division by resistors R23 and R27, a reference voltage is obtained. When the output current is too large, OCSET>1.2V, the first feedback signal output pin CSD outputs a low level. At this time, the power amplifier chip U2 does not work, which plays a protective role. When OCSET≤1.2V, the power amplifier chip U2 works normally, and the first feedback signal output pin CSD outputs a high level.

[0034] The temperature detection module includes a thermistor PR1, which is arranged on the heat sink and is used to detect the internal temperature of the power amplifier module. In this embodiment, the thermistor PR1 is a thermistor with a negative temperature coefficient.

[0035] Specifically, the temperature detection module also includes a first voltage regulating resistor R40, a second voltage regulating resistor R39 and a comparator U7A; the first reference working voltage +5V is connected to the reverse input terminal of the comparator U7A through the first voltage regulating resistor R40; at the same time, the first reference working voltage +5V is connected to the positive input terminal of the comparator U7A through the thermistor PR1 and the second voltage regulating resistor R39 in turn.

[0036] During normal operation, since the voltage at the reverse input of the comparator U7A is greater than the voltage at the forward input, the output of the comparator U7A outputs a negative voltage, and at this time, the diode D16 is turned off. When the temperature inside the machine rises, the resistance of the thermistor PR1 slowly decreases. When the voltage at the reverse input of the comparator U7A is less than the voltage at the forward input, the output outputs a positive voltage, and at this time, the diode D16 is turned on.

[0037] The signal conversion circuit of the processing module includes a first input terminal and a second input terminal; the first input terminal is connected to a first working voltage VCC, and the second input terminal is connected to a first feedback signal output pin CSD.

[0038] Specifically, the signal conversion circuit also includes a first voltage-dividing resistor R36 and a second voltage-dividing resistor R38; one end of the first voltage-dividing resistor R36 is connected to the first working voltage VCC through the first access terminal, and the other end is connected to the first detection pin (pin 31) of the MCU and one end of the second voltage-dividing resistor R38, and the other end of the second voltage-dividing resistor R38 is grounded. The signal conversion circuit also includes a first transistor Q5; the collector of the first transistor Q5 is connected to the first feedback signal output pin CSD through the second access terminal, the emitter is connected to the first reference working voltage +5V, and the base is connected to the second detection pin of the MCU (pin 32).

[0039] More specifically, the signal conversion circuit also includes a first diode D15 and a second diode D14; one end of the first diode D15 is grounded, and the other end is connected to the corresponding first detection pin (pin 31); one end of the second diode D14 is grounded, and the other end is connected to the second detection pin (pin 32).

[0040] When used specifically:

[0041] The output end of the comparator U7A is connected to the third detection pin (pin 30) of the MCU. The third detection pin (pin 30) can sample a voltage range of 0.5-3.3V; when the voltage at the reverse input end of the comparator U7A is less than the voltage at the forward input end, the diode D16 is turned on, and a voltage is provided to the third detection pin (pin 30) of the MCU through the resistor R41. The temperature program built into the MCU can output the corresponding temperature according to the different voltages read, and display it through the display module.

[0042] When the external power supply voltage is greater than 260V and less than 280V, the SD pin of the power chip U1 is greater than 5.1V. At this time, there is no voltage output on the secondary side of the transformer T1, and VCC PROT and CSD PROT (corresponding to the first detection pin and the second detection pin mentioned above) are both low levels. At this time, the MCU determines that the power supply is overvoltage.

[0043] When the external power supply voltage is greater than 110V and less than 180V, the SD pin of the power chip U1 is greater than 1.6V, the power chip U1 starts, and the secondary side of the transformer T1 (i.e., the first working voltage VCC and the second working voltage VSS) has a voltage output. Since the input voltage is relatively low, the secondary side output voltage is also very low and cannot reach the working voltage of the power amplifier chip U2. Therefore, the first feedback signal output pin CSD of the power amplifier chip U2 outputs a low level, and the first working voltage VCC is divided by resistors R16 and R17, and the voltage output to the MCU through the first detection pin is a high level. At this time, the MCU determines that the power supply is undervoltage.

[0044] When the load on the power output terminal OUT of the power amplifier module is too large, that is, when the U2 OCSET of the power amplifier chip U2 is greater than 1.2V, the output of the first feedback signal output pin CSD changes from a high level to a low level, and the power amplifier chip U2 stops working. At this time, CSDPROT is a high level, and the MCU determines that the output is overloaded.

[0045] The following is a list of MCU detection and judgment.

[0046]

[0047]

[0048] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A power amplifier device with composite fault detection, characterized in that: include: Power module, processing module, power amplifier module and display module; The power supply module includes a main power supply circuit for outputting a working voltage to supply power to the power amplifier module and the display module respectively; the working voltage includes a first working voltage and a second working voltage; The processing module includes a signal conversion circuit and an MCU, wherein the MCU is connected to the signal conversion circuit; a first access terminal of the signal conversion circuit is connected to the first working voltage; The power amplifier module includes a power output terminal and a power amplifier chip, and the power amplifier chip includes a current detection pin and a first feedback signal output pin; the current detection pin is connected to the second working voltage; The second access terminal of the signal conversion circuit is connected to the first feedback signal output pin; The display module is connected to the MCU and is used to display the detection results.

2. A power amplifier device with fault composite detection according to claim 1, characterized in that: The signal conversion circuit also includes a first voltage-dividing resistor and a second voltage-dividing resistor; One end of the first voltage-dividing resistor is connected to the first working voltage through the first access end, and the other end is connected to the first detection pin of the MCU and one end of the second voltage-dividing resistor, and the other end of the second voltage-dividing resistor is grounded.

3. A power amplifier device with composite fault detection according to claim 2, characterized in that: The operating voltage also includes a reference operating voltage; The signal conversion circuit also includes a first transistor; the collector of the first transistor is connected to the first feedback signal output pin through the second access terminal, the emitter is connected to the reference working voltage, and the base is connected to the second detection pin of the MCU.

4. A power amplifier device with composite fault detection according to claim 3, characterized in that: The signal conversion circuit also includes a first diode and a second diode; One end of the first diode and the second diode is grounded, and the other end is separately connected to the corresponding first detection pin and the second detection pin respectively.

5. A power amplifier device with composite fault detection according to claim 1, characterized in that: The power amplifier module also includes a first MOS tube and a second MOS tube; The gates of the first MOS tube and the second MOS tube are separately connected to the control pins corresponding to the power amplifier chip; the drain of the first MOS tube is connected to the first working voltage, and the source is connected to the power output end; The source of the second MOS tube is connected to the second working voltage, and the drain is connected to the power output end.

6. A power amplifier device with composite fault detection according to claim 5, characterized in that: The power amplifier module is also provided with a heat sink; The first MOS tube and the second MOS tube are fixed on the heat sink.

7. A power amplifier device with fault composite detection according to claim 6, characterized in that: It also includes a temperature detection module, which is connected to the MCU; The temperature detection module includes a thermistor, and the thermistor is arranged on the heat sink.

8. A power amplifier device with composite fault detection according to claim 7, characterized in that: The temperature detection module also includes a first voltage regulating resistor, a second voltage regulating resistor and a comparator; The reference working voltage is connected to the inverting input terminal of the comparator through the first voltage regulating resistor; The reference working voltage is connected to the positive input terminal of the comparator through the thermistor and the second voltage regulating resistor in sequence; The output end of the comparator is connected to the third detection pin of the MCU.

9. A power amplifier device with composite fault detection according to claim 8, characterized in that: The thermistor is a thermistor with a negative temperature coefficient.

10. A power amplifier device with fault composite detection according to any one of claims 1 to 9, characterized in that: The power supply module further includes an auxiliary power supply circuit, wherein the main power supply circuit is connected to an input end of the auxiliary power supply circuit and is used to supply power to the auxiliary power supply circuit; The input end of the auxiliary power supply circuit is connected to the MCU and is used to provide a third operating voltage for the MCU.

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