CN213754721U - MCU silence circuit that resets - Google Patents
MCU silence circuit that resets Download PDFInfo
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- CN213754721U CN213754721U CN202022753003.6U CN202022753003U CN213754721U CN 213754721 U CN213754721 U CN 213754721U CN 202022753003 U CN202022753003 U CN 202022753003U CN 213754721 U CN213754721 U CN 213754721U
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Abstract
The utility model relates to the technical field of MCU mute control, and provides an MCU reset mute circuit, which comprises a reset switch, a reset module, a mute module and a reset module, wherein the reset module, the mute module and the reset module are connected with the reset switch; the reset module comprises an auxiliary circuit and a switch circuit; the utility model discloses when control reset switch resets MCU by force, the high level signal of reset switch output on the one hand transmits to the silence module and then exports power amplifier silence end, carries out the silence; on the other hand, the switch circuit is controlled to be conducted, the voltage of the reset end of the MCU is pulled down, and meanwhile, when the auxiliary circuit detects that the voltage is lower than a preset threshold value, a low level signal is output to drive the MCU to execute forced reset operation, so that the reliability of each reset of the MCU is ensured; and a reset module is arranged to normally supply power to the auxiliary circuit when the high level signal output by the reset switch is output, and reset the input signal of the auxiliary circuit when the low level signal is output by the reset switch, so that whether the MCU is reset or not can be correspondingly controlled according to the state of the reset switch.
Description
Technical Field
The utility model relates to a control circuit technical field especially relates to a MCU silence circuit that resets.
Background
The mute circuit is widely applied to various electronic products, such as vehicle multimedia, television and the like.
The existing common mute circuit controls a power amplifier circuit through an I/O end of an MCU (microprogrammed control Unit) to realize the mute function; however, when the MCU has a hang-up failure and needs to be reset, mute control cannot be performed, resulting in a "pop, which affects user experience.
In addition, the mute circuit generally adopts a switching tube to establish an MCU reset circuit, and the conduction internal resistance of the triode is greatly increased after the switching tube is in a severe environment or the switching tube is aged, so that the MCU cannot be reset.
SUMMERY OF THE UTILITY MODEL
The utility model provides a MCU silence circuit that resets has solved that current MCU silence circuit silence control limitation is big, easily receive MCU influence of resetting, and the triode is ageing or adverse circumstances will make MCU reset unusual technical problem.
In order to solve the technical problem, the utility model provides an MCU reset mute circuit, which comprises a reset switch, and a reset module, a mute module and a reset module which are respectively connected with the reset switch; the reset module comprises an auxiliary circuit and a switch circuit; the output end of the mute module is connected with the mute end of the power amplifier, the output end of the switch circuit is connected with the reset end of the MCU, and the reset end of the MCU and the reset module are both connected with the auxiliary circuit.
According to the basic scheme, when the reset switch is controlled to forcibly reset the MCU, a high-level signal output by the reset switch is transmitted to the mute module and then output to the power amplifier mute end to execute muting; on the other hand, the switch circuit is controlled to be conducted, the voltage of the reset end of the MCU is pulled down, and meanwhile, when the auxiliary circuit detects that the voltage is lower than a preset threshold value, a low level signal is output to drive the MCU to execute forced reset operation, so that the reliability of each reset of the MCU is ensured; and a reset module is arranged to normally supply power to the auxiliary circuit when the high level signal output by the reset switch is output, and reset the input signal of the auxiliary circuit when the reset switch outputs the low level (after being released), so that whether the MCU is reset or not can be correspondingly controlled according to the state of the reset switch.
In a further embodiment, the switching circuit includes a first switching tube, a second switching tube, a third switching tube, a first diode, a first resistor, a second resistor, a third resistor, a first capacitor, and a second capacitor;
when the first switch tube, the second switch tube and the third switch tube are all NPN type triodes, the base electrode of the first switch tube is connected to the reset switch through a first resistor, the emitting electrode of the first switch tube is grounded, the collector electrode of the first switch tube passes through one end of a second resistor, and the other end of the second resistor is connected to a first power supply end; the anode of the first diode is connected with the reset switch, and the cathode of the first diode is connected with one end of the third resistor; the base electrode of the second switch tube is connected with one end of the second resistor, the emitter electrode of the second switch tube is grounded, and the collector electrode of the second switch tube is connected with the other end of the third resistor; the other end of the third resistor is also connected with the base electrode of the third switching tube and is grounded through the first capacitor; the emitter of the third switching tube is grounded, and the collector of the third switching tube is connected with the reset end of the MCU; one end of the second capacitor is connected to the MCU reset end, and the other end of the second capacitor is grounded.
In a further embodiment, the auxiliary circuit includes a second diode and a reset chip; the first end of the reset chip is connected with the reset module and is also connected with the MCU reset end through the second diode, the second end of the reset chip is grounded, and the third end of the reset chip is connected with the output end of the switch circuit.
According to the scheme, the switching function of the switching tube is utilized, when the reset switch is switched on, the whole switching circuit is switched on, and the collector and the emitter of the third switching tube are switched on at the moment, so that the reset end of the MCU is grounded, namely the voltage of the reset end of the MCU is pulled down; at the moment, the reset chip detects that the voltage of the MCU reset end is lower than a preset threshold value from the first end, controls the third end to output low level and controls the MCU to reset; the double reset circuit with the integrated switch tube and the reset chip can improve the anti-interference capability of the circuit, and even if the switch tube is aged or in a severe environment, the MCU can still quickly execute reset.
In a further embodiment, the reset module includes fourth to sixth resistors, a fourth switch tube, a first voltage regulator tube, a first inductor, and third to fifth capacitors;
when the fourth switching tube is an NPN type triode, the reset switch is connected to the base electrode of the fourth switching tube through the fourth resistor; a collector of the fourth switch tube is connected with a second power supply end, an emitter of the fourth switch tube is connected with one end of the first inductor, and a base of the fourth switch tube is grounded through the fifth resistor, the first voltage regulator tube and the third capacitor respectively; the second power supply end is also connected to the anode of the second diode through the sixth resistor; the other end of the first inductor is connected to the first end of the reset chip and is grounded through the fourth capacitor and the fifth capacitor respectively.
This scheme has set up corresponding reset module to the chip that resets, designs the fourth switch tube who connects reset switch in reset module, can survey present reset switch's the state that opens and shuts effectively, and then when reset chip carries out the operation that resets, provides stable voltage, and when reset switch disconnection stopped the operation that resets, reset chip's first end and third end were relieved previous reset state and were prepared for carrying out the operation that resets next time.
In a further embodiment, the mute module includes a third diode, a seventh resistor, a fifth switch tube, and a sixth capacitor;
when the fifth switching tube is an NPN-type triode, the anode of the third diode is connected to the reset switch, the cathode of the third diode is connected to one end of the seventh resistor, the base of the fifth switching tube is connected to the first power supply end, the collector of the fifth switching tube is connected to the other end of the seventh resistor, the mute end of the power amplifier and the emitter of the seventh resistor are grounded; one end of the sixth capacitor is connected with the collector of the fifth switch tube, and the other end of the sixth capacitor is grounded.
The mute module is connected at reset switch's output to this scheme, and when carrying out the operation that resets, the fifth switch tube of synchronous drive exports the high level to power amplifier mute end, controls the power amplifier module silence that corresponds to eliminate the plosiveness that MCU reset production, further improve user's use and experience.
In a further embodiment, the reset chip is of type KIA 7019.
In a further embodiment, the first to fifth switching tubes may be a triode or a MOS tube.
In a further embodiment, the first capacitor, the fifth capacitor and the sixth capacitor are all electrolytic capacitors.
Drawings
Fig. 1 is a hardware circuit diagram of an MCU reset mute circuit provided in an embodiment of the present invention;
wherein: the reset module 1, the auxiliary circuit 11 and the switch circuit 12; a mute module 2 and a reset module 3;
MCU REST at MCU reset terminal; a power amplifier MUTE end MUTE; resetting a switch REST _ KEY;
the circuit comprises a first switch tube Q1-a fifth switch tube Q5, a first resistor R1-a seventh resistor R7, a first capacitor EC1, a second capacitor C1-a fourth capacitor C3, a fifth capacitor EC2 and a sixth capacitor EC 3; the diode comprises a first diode D1-a third diode D3, a first voltage regulator tube Z1 and a first inductor L1; chip U1 is reset.
Detailed Description
The following embodiments of the present invention will be described in detail with reference to the accompanying drawings, which are given for illustrative purposes only and are not to be construed as limiting the invention, including the drawings, which are only used for reference and illustration, and do not constitute a limitation to the scope of the invention, since many changes may be made thereto without departing from the spirit and scope of the invention.
The embodiment of the utility model provides a MCU silence circuit that resets, as shown in fig. 1, in this embodiment, include reset switch REST _ KEY, and reset module 1, silence module 2, reset module 3 that are connected with reset switch REST _ KEY respectively; the reset module 1 includes an auxiliary circuit 11 and a switch circuit 12; the output end of the MUTE module 2 is connected with a power amplifier MUTE end MUTE, the output end of the switch circuit 12 is connected with an MCU reset end MCU REST, and the MCU reset end MCU REST and the reset module 3 are both connected with an auxiliary circuit 11.
When the reset switch REST _ KEY is pressed down, a high level is output, otherwise, a low level is output; in this embodiment, the MCU reset terminal MCU REST is active low, that is, the MCU reset terminal MCU REST performs reset when it is active low.
In this embodiment, the switch circuit 12 includes a first switch Q1, a second switch Q2, a third switch Q3, a first diode D1, a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor EC1, and a second capacitor C1;
when the first switch tube Q1, the second switch tube Q2 and the third switch tube Q3 are all NPN-type triodes, the base of the first switch tube Q1 is connected to the reset switch REST _ KEY through the first resistor R1, the emitter is grounded, the collector passes through one end of the second resistor R2, and the other end of the second resistor R2 is connected to the first power supply terminal (e.g., 8V interface in fig. 1); the positive electrode of the first diode D1 is connected with the reset switch REST _ KEY, and the negative electrode of the first diode D1 is connected with one end of the third resistor R3; the base of the second switch tube Q2 is connected with one end of the second resistor R2, the emitter is grounded, and the collector is connected with the other end of the third resistor R3; the other end of the third resistor R3 is also connected with the base of a third switching tube Q3 and is grounded through a first capacitor EC 1; the emitter of the third switching tube Q3 is grounded, and the collector is connected with the MCU REST; one end of the second capacitor C1 is connected to the MCU reset terminal MCU REST, and the other end is grounded.
In the present embodiment, the auxiliary circuit 11 includes a second diode D2 and a reset chip U1; the reset chip U1 has a first terminal (voltage detection terminal) connected to the reset module 3 and further connected to the MCU reset terminal MCU REST through a second diode D2, a second terminal (ground terminal) connected to ground, and a third terminal (voltage output terminal) connected to the output terminal of the switching circuit 12.
The model of the reset chip U1 is KIA 7019.
In this embodiment, by using the switching function of the switching tube, when the reset switch REST _ KEY is turned on, the whole switching circuit 12 is turned on, and at this time, the collector and the emitter of the third switching tube Q3 are turned on, so that the MCU reset terminal MCU REST is grounded, that is, the MCU reset terminal MCU REST voltage is pulled low; at the moment, the reset chip U1 detects that the voltage of the MCU reset terminal MCU REST is lower than a preset threshold value from the first terminal, controls the third terminal to output low level and controls the MCU to reset; the anti-interference capability of the circuit can be improved by arranging the dual reset circuit of the integrated switch tube and the reset chip U1, and even if the switch tube is aged or in a severe environment, the MCU can still quickly execute reset.
In this embodiment, the reset module 3 includes fourth to sixth resistors R4 to R6, a fourth switch Q4, a first voltage regulator Z1, a first inductor L1, and third to fifth capacitors C2 to EC 2;
when the fourth switching tube Q4 is an NPN-type triode, the reset switch REST _ KEY is connected to the base of the fourth switching tube Q4 through a fourth resistor R4; a collector of the fourth switching tube Q4 is connected to a second power supply terminal (as an A5V interface in fig. 1), an emitter is connected to one end of the first inductor L1, and a base is grounded through a fifth resistor R5, a first voltage regulator tube Z1, and a third capacitor C2, respectively; the second power supply terminal is also connected to the anode of a second diode D2 through a sixth resistor R6; the other end of the first inductor L1 is connected to the first end of the reset chip U1, and is grounded through the fourth capacitor C3 and the fifth capacitor EC2, respectively.
The first inductor L1 may store electric energy, and after the fourth switching tube Q4 is turned off, power is continuously supplied to the reset chip U1 (i.e., a freewheeling function), so that the power supply level changes gradually.
The embodiment is provided with a reset module 3 for the reset chip U1, and the fourth switch Q4 connected to the reset switch REST _ KEY is designed in the reset module 3, so that the on-off state of the current reset switch REST _ KEY can be effectively detected, and further, when the reset chip U1 performs the reset operation, a stable voltage is provided, and when the reset switch REST _ KEY is turned off and stops the reset operation, the first terminal and the third terminal of the reset chip U1 are reset, the previous reset state is released, and preparation is made for the next reset operation.
In this embodiment, the mute module 2 includes a third diode D3, a seventh resistor R7, a fifth switch Q5 and a sixth capacitor EC 3;
when the fifth switching tube Q5 is an NPN type triode, the anode of the third diode D3 is connected to the reset switch REST _ KEY, the cathode is connected to one end of the seventh resistor R7, the base of the fifth switching tube Q5 is connected to the first power terminal, the collector is connected to the other end of the seventh resistor R7, the power amplifier MUTE terminal MUTE, and the emitter is grounded; one end of the sixth capacitor EC3 is connected to the collector of the fifth switching tube Q5, and the other end is grounded.
The power amplifier MUTE end MUTE is a MUTE pin of the power amplifier module, and when the power amplifier MUTE end MUTE detects a high level, MUTE operation is executed.
In this embodiment, the MUTE module 2 is connected to the output end of the reset switch REST _ KEY, and when the reset operation is executed, the fifth switch tube Q5 is synchronously driven to output a high level to the power amplifier MUTE end MUTE, so as to control the MUTE of the corresponding power amplifier module, thereby eliminating the pop generated by the reset of the MCU and further improving the user experience.
In this embodiment, the first to fifth switching tubes Q1 to Q5 are all triodes or MOS tubes.
The first diode D1 and the third diode D3 are used for preventing the voltages of the MCU and the power amplifier module from interfering with the conduction state of the first switch tube Q1, so that the conduction state of the first switch tube Q1 is controlled only by the signal transmitted by the reset switch REST _ KEY; the second diode D2 is used to prevent the electrical signal of the reset module 3 from interfering with the MCU reset.
In the embodiment, the first capacitor EC1, the fifth capacitor EC2 and the sixth capacitor EC3 are electrolytic capacitors; the first capacitor EC1 to the sixth capacitor EC3 are mainly used for delaying time and preventing the reset switch REST _ KEY from being touched by mistake to cause the reset mode to be entered.
Taking the first to fifth switching tubes Q1 to Q5 as NPN-type triodes, the first power end outputting 8V voltage, the second power end outputting 5V voltage as an example, the specific working process of this embodiment is as follows:
when the reset switch REST _ KEY is pressed, a high level is output:
the emitter of the first switch tube Q1 is connected with the collector, the second switch tube Q2 and the fifth switch tube Q5 are cut off, the high level is directly output to the MUTE end MUTE of the power amplifier through the third diode D3 and the seventh resistor R7, and the power amplifier module is driven to execute MUTE operation.
Meanwhile, the high level output by the reset switch REST _ KEY is output to the base of the third switch Q3 through the first diode D1 and the third resistor R3, the third switch Q3 is turned on, and the voltage of the MCU reset terminal MCU REST is pulled down. At this time, the reset chip U1 detects that the voltage of the MCU reset terminal MCU REST is lower than a preset threshold (e.g., 2.3V) through the first terminal, and controls the third terminal to output a low level signal to control the MCU reset.
In addition, the high level output by the REST _ KEY end also turns on the fourth switch tube Q4, so that the voltage at the second power supply end is output to the first end of the reset chip U1 after passing through the first voltage regulator tube Z1, that is, the reset chip U1 is powered.
When the reset switch REST _ KEY is released from pressing, a low level is output:
the first switch tube Q1 is turned off, and the fifth switch tube Q5 is turned on, so that the power amplifier module works normally.
The second switch tube Q2 switches on, the third switch tube Q3 cuts off, the voltage that MCU reset end MCU REST was pulled up to A5V, reset chip U1 is out of work, fourth switch tube Q4 cuts off, the voltage of second power end loops through sixth resistance R6, second diode D2 supplies power to the first end of resetting chip U1, make the third end output high level, thereby make and reset chip U1 reset.
When the reset switch REST _ KEY is controlled to forcibly reset the MCU, on the one hand, the high level signal output by the reset switch REST _ KEY is transmitted to the MUTE module 2 and then output to the power amplifier MUTE end MUTE, so as to execute MUTE; on the other hand, the control switch circuit 12 is turned on, the voltage of the reset end MCU REST of the MCU is pulled down, and meanwhile, when the auxiliary circuit 11 detects that the voltage is lower than a preset threshold value, a low level signal is output to drive the MCU to execute a forced reset operation, so that the reliability of each reset of the MCU is ensured; and a reset module 3 is arranged to normally supply power to the auxiliary circuit 11 when the reset switch REST _ KEY outputs a high level signal, and reset the input signal of the auxiliary circuit 11 when the reset switch REST _ KEY outputs a low level signal (after being released), so that whether the MCU is reset or not can be correspondingly controlled according to the state of the reset switch REST _ KEY.
The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be equivalent replacement modes, and all are included in the scope of the present invention.
Claims (6)
1. The utility model provides a MCU silence circuit that resets, includes reset switch, its characterized in that: the reset module, the mute module and the reset module are respectively connected with the reset switch; the reset module comprises an auxiliary circuit and a switch circuit; the output end of the mute module is connected with the mute end of the power amplifier, the output end of the switch circuit is connected with the reset end of the MCU, and the reset end of the MCU and the reset module are both connected with the auxiliary circuit.
2. The MCU reset mute circuit of claim 1, wherein: the switch circuit comprises a first switch tube, a second switch tube, a third switch tube, a first diode, a first resistor, a second resistor, a third resistor, a first capacitor and a second capacitor;
when the first switch tube, the second switch tube and the third switch tube are all NPN type triodes, the base electrode of the first switch tube is connected to the reset switch through a first resistor, the emitting electrode of the first switch tube is grounded, the collector electrode of the first switch tube passes through one end of a second resistor, and the other end of the second resistor is connected to a first power supply end; the anode of the first diode is connected with the reset switch, and the cathode of the first diode is connected with one end of the third resistor; the base electrode of the second switch tube is connected with one end of the second resistor, the emitter electrode of the second switch tube is grounded, and the collector electrode of the second switch tube is connected with the other end of the third resistor; the other end of the third resistor is also connected with the base electrode of the third switching tube and is grounded through the first capacitor; the emitter of the third switching tube is grounded, and the collector of the third switching tube is connected with the reset end of the MCU; one end of the second capacitor is connected to the MCU reset end, and the other end of the second capacitor is grounded.
3. The MCU reset mute circuit of claim 1, wherein: the auxiliary circuit comprises a second diode and a reset chip; the first end of the reset chip is connected with the reset module and is also connected with the MCU reset end through the second diode, the second end of the reset chip is grounded, and the third end of the reset chip is connected with the output end of the switch circuit.
4. The MCU reset mute circuit of claim 3, wherein: the reset module comprises a fourth resistor, a fifth resistor, a sixth resistor, a fourth switch tube, a first voltage regulator tube, a first inductor, a third capacitor, a fourth capacitor and a fifth capacitor;
when the fourth switching tube is an NPN type triode, the reset switch is connected to the base electrode of the fourth switching tube through the fourth resistor; a collector of the fourth switch tube is connected with a second power supply end, an emitter of the fourth switch tube is connected with one end of the first inductor, and a base of the fourth switch tube is grounded through the fifth resistor, the first voltage regulator tube and the third capacitor respectively; the second power supply end is also connected to the anode of the second diode through the sixth resistor; the other end of the first inductor is connected to the first end of the reset chip and is grounded through the fourth capacitor and the fifth capacitor respectively.
5. The MCU reset mute circuit of claim 1, wherein: the mute module comprises a third diode, a seventh resistor, a fifth switch tube and a sixth capacitor;
when the fifth switching tube is an NPN-type triode, the anode of the third diode is connected to the reset switch, the cathode of the third diode is connected to one end of the seventh resistor, the base of the fifth switching tube is connected to the first power supply end, the collector of the fifth switching tube is connected to the other end of the seventh resistor, the mute end of the power amplifier and the emitter of the seventh resistor are grounded; one end of the sixth capacitor is connected with the collector of the fifth switch tube, and the other end of the sixth capacitor is grounded.
6. The MCU reset mute circuit of claim 3, wherein: the model of the reset chip is KIA 7019.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022753003.6U CN213754721U (en) | 2020-11-24 | 2020-11-24 | MCU silence circuit that resets |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022753003.6U CN213754721U (en) | 2020-11-24 | 2020-11-24 | MCU silence circuit that resets |
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| CN213754721U true CN213754721U (en) | 2021-07-20 |
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| CN202022753003.6U Active CN213754721U (en) | 2020-11-24 | 2020-11-24 | MCU silence circuit that resets |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114253381A (en) * | 2021-12-23 | 2022-03-29 | 厦门四信通信科技有限公司 | Electronic equipment and abnormal reset circuit thereof |
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- 2020-11-24 CN CN202022753003.6U patent/CN213754721U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114253381A (en) * | 2021-12-23 | 2022-03-29 | 厦门四信通信科技有限公司 | Electronic equipment and abnormal reset circuit thereof |
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