CN202652374U - A television set and its mute auxiliary control circuit - Google Patents

Abstract

The utility model is suitable for the technical field of television control, provides a television and a mute auxiliary control circuit thereof. In the utility model, the mute auxiliary control circuit comprising a first mute control signal generating unit and a second mute control signal generating unit is used for realizing the mute function to realize the mute control of a speaker power amplification circuit and an earphone operation amplification circuit when the television is powered up and powered down, and normally works and a user needs the mute function, and the structure of the whole mute auxiliary control circuit is simple, and the cost is effectively reduced, therefore the problems of the prior art that the circuit structure o the mute circuit is complicated and the cost is high, are solved.

Description

A television set and its mute auxiliary control circuit

technical field

The utility model belongs to the field of television control, in particular to a television and its mute auxiliary control circuit.

Background technique

At present, in terms of mute control when the TV is powered on and off, a mute circuit used in the prior art is to charge the speaker power amplifier circuit and earphone op amp of the TV through an RC charging circuit when the TV system is powered on. The circuit realizes the mute control, and when the TV system is powered off, the speaker power amplifier circuit and the earphone op-amp circuit of the TV are realized through the RC discharge circuit to realize the mute control.

However, because the structure of the mute circuit provided by the prior art is complex, and two capacitors with large capacitances are required, the cost of the entire mute circuit is increased. Therefore, the mute circuit provided by the prior art has the problems of complicated circuit structure and high cost.

Utility model content

The utility model provides a mute auxiliary control circuit of a television set, aiming at solving the problems of complicated circuit structure and high cost in the mute circuit provided by the prior art.

The utility model is achieved in that a mute auxiliary control circuit of a television is connected with the main control chip of the television, a loudspeaker power amplifier circuit, an earphone op-amp circuit and a DC power supply, and the mute auxiliary control circuit includes:

The power supply terminal is connected to the output terminal of the DC power supply, and the output terminal is connected with the mute control terminal of the speaker power amplifier circuit and the mute control terminal of the earphone operational amplifier circuit at the same time, and generates a mute control signal when the TV is powered on and powered off The first mute control signal generating unit;

The power supply terminal is connected to the output end of the DC power supply, and the input end and the output end are respectively connected to the general I/O port of the main control chip and the input end of the first mute control signal generation unit, and the TV works normally , a second mute control signal generation unit that generates a corresponding mute control signal according to the level signal output by the main control chip.

Another object of the present utility model is to provide a TV set, which includes a main control chip, a loudspeaker power amplifier circuit, an earphone op-amp circuit, a DC power supply, and a mute auxiliary control circuit. The main control chip, the loudspeaker power amplifier circuit, the earphone operational amplifier circuit and the DC power supply are connected, and the mute auxiliary control circuit includes:

The power supply terminal is connected to the output terminal of the DC power supply, and the output terminal is connected with the mute control terminal of the speaker power amplifier circuit and the mute control terminal of the earphone operational amplifier circuit at the same time, and generates a mute control signal when the TV is powered on and powered off The first mute control signal generating unit;

The power supply terminal is connected to the output end of the DC power supply, and the input end and the output end are respectively connected to the general I/O port of the main control chip and the input end of the first mute control signal generation unit, and the TV works normally , a second mute control signal generation unit that generates a corresponding mute control signal according to the level signal output by the main control chip.

In the utility model, by adopting the mute auxiliary control circuit comprising the first mute control signal generating unit and the second mute control signal generating unit, it is possible to power on, power off, and the TV is working normally and the user needs When the mute function is realized, the mute control signal is stably output to realize the mute control of the loudspeaker power amplifier circuit and the earphone operational amplifier circuit, and the circuit structure of the whole mute auxiliary control circuit is simple, which effectively reduces the cost, thereby solving the problem of The mute circuit provided by the prior art has the problems of complicated circuit structure and high cost.

Description of drawings

Fig. 1 is a block diagram of the mute auxiliary control circuit provided by the first embodiment of the utility model;

Fig. 2 is an example circuit structure diagram of the mute auxiliary control circuit provided by the second embodiment of the present invention;

Fig. 3 is an example circuit structure diagram of the mute auxiliary control circuit provided by the third embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

In the embodiment of the present invention, by adopting the mute auxiliary control circuit including the first mute control signal generating unit and the second mute control signal generating unit, it is possible to realize mute when the TV is powered on, powered off, and the TV is working normally and the user needs to When functioning, the mute control signal is stably output to realize mute control for the speaker power amplifier circuit and the earphone op-amp circuit, and the circuit structure of the whole mute auxiliary control circuit is simple, which effectively reduces the cost.

The concrete realization of the present utility model is described in detail below in conjunction with specific embodiment:

Embodiment one:

Fig. 1 shows the module structure of the mute auxiliary control circuit provided by the first embodiment of the utility model, for the convenience of explanation, only shows the part relevant to the first embodiment of the utility model, detailed description is as follows:

The mute auxiliary control circuit 100 of the television is connected with the main control chip 200 of the television, the loudspeaker power amplifier circuit 300, the earphone operational amplifier circuit 400 and the DC power supply 500, and the mute auxiliary control circuit 100 includes:

The power supply terminal is connected to the output end of the DC power supply 500, and the output end is connected with the mute control end of the speaker power amplifier circuit 300 and the mute control end of the earphone operational amplifier circuit 400 at the same time, and generates the first mute control signal when the TV is powered on and powered off. Mute control signal generation unit 101;

The power supply terminal is connected to the output end of the DC power supply 500, and the input end and the output end are respectively connected with the general-purpose I/O port of the main control chip 200 and the input end of the first mute control signal generation unit 101. When the TV is working normally, according to The level signal output by the main control chip 200 generates the second mute control signal generation unit 102 corresponding to the mute control signal.

Embodiment two:

Fig. 2 shows the exemplary circuit structure of the mute auxiliary control circuit provided by the second embodiment of the present invention. For the convenience of explanation, only the parts related to the second embodiment of the present invention are shown, and the details are as follows:

As an embodiment of the present invention, the first mute control signal generating unit 101 includes:

Resistor R1, PNP transistor Q1, energy storage capacitor C1, diode D1, diode D2, resistor R2, resistor R3, resistor R4, and NPN transistor Q2;

The first end of the resistor R1 is the power supply end of the first mute control signal generating unit 101, the base of the PNP transistor Q1 is connected to the first end of the resistor R1, and the emitter of the PNP transistor Q1 is connected to the second end of the resistor R1. The positive pole of the energy storage capacitor C1, the negative pole of the energy storage capacitor C1 and the cathode of the diode D1 are commonly connected to the anode of the diode D2, the anode of the diode D1 is grounded, and the cathode of the diode D2 is the input end of the first mute control signal generating unit 101, The resistor R2 is connected between the collector of the PNP transistor Q1 and the cathode of the diode D2, the base of the NPN transistor Q2 is simultaneously connected with the cathode of the diode D2 and the first end of the resistor R3, and the second end of the resistor R3 is grounded. The emitter of the NPN transistor Q2 is grounded, the collector of the NPN transistor Q2 is the output terminal of the first mute control signal generating unit 101, and the resistor R4 is connected between the first end of the resistor R1 and the collector of the NPN transistor Q2.

As an embodiment of the present invention, the second mute control signal generating unit 102 includes:

Resistor R5, energy storage capacitor C2, NPN transistor Q3, resistor R6 and diode D3;

The first end of the resistor R5 is the input end of the second mute control signal generating unit 102, the second end of the resistor R5 and the positive pole of the energy storage capacitor C2 are connected to the base of the NPN transistor Q3, and the negative pole of the energy storage capacitor C2 is connected to the base of the NPN transistor Q3. The emitters of the NPN transistor Q3 are grounded, the collector of the NPN transistor Q3 is connected to the first end of the resistor R6 and the anode of the diode D3 at the same time, and the second end of the resistor R6 and the cathode of the diode D3 are respectively the second mute control The power terminal and the output terminal of the signal generating unit 102 .

In this embodiment, both the mute control terminal of the speaker power amplifier circuit 300 and the mute control terminal of the earphone operational amplifier circuit 400 need to use a low level as a mute control signal to trigger the mute function.

The following is a further description of the mute auxiliary control circuit combined with the working principle:

When the TV system is turned on and powered on, the level signal output by the general-purpose I/O port of the main control chip 200 is unstable, and the cathode of the diode D3 cannot output an effective high level to drive the NPN transistor Q2 to conduct, so the DC The DC power output by the power supply 500 after power-on charges the energy storage capacitor C1 through the resistor R1. At the same time, the DC power is output by the cathode of the diode D2, and is divided by the resistor R3 to provide the base bias voltage for the NPN transistor Q2. , then the NPN transistor Q2 is turned on, and pulls current from the resistor R4 so that its collector changes from a high potential to a low potential, then the collector of the NPN transistor Q2 outputs a low level as a mute control signal to make the speaker power amplifier circuit 300 and the earphone operational amplifier circuit 400 all enter the mute state, so as to avoid the power-on impact sound from the speaker and the earphone. As the energy storage capacitor C1 continues to charge, the direct current flowing from the diode D2 to the base of the NPN transistor Q2 will continue to decrease. When the energy storage capacitor C1 is fully charged, the base voltage of the NPN transistor Q2 is less than its bias voltage and cut off, at this time the collector of the NPN transistor Q2 changes from a low potential to a high potential, then the mute control terminal of the speaker power amplifier circuit 300 and the mute control terminal of the earphone operational amplifier circuit 400 are obtained from the collector of the NPN transistor Q2 High level to cancel the mute function. At this time, the TV is powered on and turned on, and the TV system starts to enter the normal working state.

When the TV system is working normally, if the user inputs a mute trigger command, the main control chip 200 will output a low level from its general-purpose I/O port, and the low level will enter the base of the NPN transistor Q3 through the resistor R5. The NPN transistor Q3 is cut off, and the DC power output by the DC power supply 500 is output to the base of the NPN transistor Q2 through the resistor R6 and the diode D3. Therefore, the NPN transistor Q2 is turned on and its collector draws current from the resistor R4, and the NPN transistor The collector of Q2 outputs a low level as a mute control signal to make the speaker power amplifier circuit 300 and the earphone op-amp circuit 400 enter the mute state; Output a high level, the high level enters the base of the NPN transistor Q3 through the resistor R5, the NPN transistor Q3 is turned on and pulls current from the first end of the resistor R6 through its collector, at this time the diode D3 outputs a low voltage The NPN transistor Q2 is cut off, and the resistor R4 directly introduces the DC output from the DC power supply 500 to the collector of the NPN transistor Q2, so that the collector of the NPN transistor Q2 outputs a high level to cancel the operation of the speaker power amplifier circuit 300 and the earphone. Turn off the mute function of the playback circuit 400 to stop the mute.

When the TV system is turned off and powered off, the level signal output by the general-purpose I/O port of the main control chip 200 is unstable, and the cathode of the diode D3 cannot output an effective high level to drive the NPN transistor Q2 to conduct, and the DC power supply The 500 stops outputting direct current. At this time, the PNP transistor Q1 is turned on, and the energy storage capacitor C1 starts to discharge. The current flows to the base of the NPN transistor Q2 through the PNP transistor Q1 and the resistor R2. The NPN transistor Q2 is turned on and its collector Outputting a low level as a mute control signal makes the speaker power amplifier circuit 300 and the earphone operational amplifier circuit 400 both enter the mute state, so as to avoid the power-off impact sound from the speaker and the earphone. With the gradual advancement of the discharge process of the energy storage capacitor C1, the voltage at the two poles of the energy storage capacitor C1 will gradually decrease, and the current flowing through the resistor R2 to the base of the NPN transistor Q2 will also gradually decrease. When the energy storage capacitor C1 is discharged At the end, the NPN transistor Q2 is cut off. At this time, since the DC power supply 500 has no DC output, no current flows through the resistor R4, and the collector of the NPN transistor Q2 maintains a low potential.

In this embodiment, an energy storage capacitor C1 with a specific capacitance and a resistor R1 with a specific resistance value are selected according to the power-on initialization time of the main control chip 200, so that the charging time of the energy storage capacitor C1 is the same as that of the main control chip 200. The power-on initialization time is consistent to ensure that the impact sound of power-on can be completely shielded, and at the same time, a resistor R2 with a specific resistance needs to be selected according to the discharge time of the energy storage capacitor C1, so that it can be used during the discharge of the energy storage capacitor C1. The impact sound is fully shielded.

Embodiment three:

Fig. 3 shows the exemplary circuit structure of the mute auxiliary control circuit provided by the third embodiment of the present invention. For the convenience of explanation, only the parts related to the third embodiment of the present invention are shown, and the details are as follows:

As an embodiment of the present invention, the first mute control signal generation unit 101 includes:

Resistor R7, PNP transistor Q4, energy storage capacitor C3, diode D4, diode D5, resistor R8 and resistor R9;

The first end of the resistor R7 is the power supply end of the first mute control signal generating unit 101, the base of the PNP transistor Q4 is connected to the first end of the resistor R7, and the emitter of the PNP transistor Q4 is connected to the second end of the resistor R7. The positive pole of the energy storage capacitor C3, the negative pole of the energy storage capacitor C3 and the cathode of the diode D4 are commonly connected to the anode of the diode D5, the anode of the diode D4 is grounded, and the cathode of the diode D5 is the input end of the first mute control signal generating unit 101, The resistor R8 is connected between the collector of the PNP transistor Q4 and the cathode of the diode D4, the first end of the resistor R9 is the output end of the first mute control signal generating unit 101 and is connected to the cathode of the diode D5, the second end of the resistor R9 end grounded.

In this embodiment, the circuit structure of the second mute control signal generating unit 102 is the same as the circuit structure provided in the second embodiment of the present invention, so it will not be repeated here.

In this embodiment, both the mute control terminal of the speaker power amplifier circuit 300 and the mute control terminal of the earphone operational amplifier circuit 400 need to use a high level as a mute control signal to trigger the mute function.

The following is a further description of the mute auxiliary control circuit combined with the working principle:

When the TV system is turned on and powered on, the level signal output by the general-purpose I/O port of the main control chip 200 is unstable, and the cathode of the diode D3 cannot output an effective high level. The output direct current charges the energy storage capacitor C3 through the resistor R7, and at the same time, the direct current is output by the cathode of the diode D5, and after being divided by the resistor R9, a high level is output as a mute control signal to make the speaker power amplifier circuit 300 and the earphone op amp The circuits 400 all enter the mute state, so as to avoid the power-on impact sound from the speaker and the earphone. As the energy storage capacitor C1 continues to charge, the output current from the diode D5 will continue to decrease. When the energy storage capacitor C3 is fully charged, the cathode of the diode D5 stops outputting current, and the first end of the resistor R9 changes from a high potential to a low potential , then the mute control terminal of the speaker power amplifier circuit 300 and the mute control terminal of the headphone operational amplifier circuit 400 both get a low level from the first end of the resistor R9 to cancel the mute function. At this time, the TV is powered on and the TV system starts into normal working condition.

When the TV system is working normally, if the user inputs a mute trigger command, the main control chip 200 will output a low level from its general-purpose I/O port, and the low level will enter the base of the NPN transistor Q3 through the resistor R5. The NPN transistor Q3 is cut off, and the DC power output by the DC power supply 500 is output to the first end of the resistor R9 through the resistor R6 and the diode D3. After the DC power is divided by the resistor R9, the first end of the resistor R9 outputs a high level as a mute The control signal makes the speaker power amplifier circuit 300 and the earphone operational amplifier circuit 400 all enter the mute state; if the user inputs a mute cancel command, the main control chip 200 will output a high level from its general-purpose I/O port, and the high level will pass through the resistor R5 enters the base of the NPN transistor Q3, the NPN transistor Q3 is turned on and pulls current from the first end of the resistor R6 through its collector, at this time the cathode of the diode D3 outputs a low level to the first end of the resistor R9, thus Make the speaker power amplifier circuit 300 and the earphone operational amplifier circuit 400 cancel the mute function, and stop the mute.

When the TV system is powered off and the level signal output by the general-purpose I/O port of the main control chip 200 is unstable, the cathode of the diode D3 cannot output an effective high level, and the DC power supply 500 stops outputting DC power. The PNP transistor Q4 is turned on, the energy storage capacitor C3 starts to discharge, the current flows to the first end of the resistor R9 through the PNP transistor Q4 and the resistor R8, and then the resistor R9 divides the voltage and outputs a high level from its first end as The mute control signal makes the speaker power amplifier circuit 300 and the earphone operational amplifier circuit 400 both enter the mute state, so as to prevent the speaker and the earphone from making a power-off impact sound. With the gradual advancement of the discharge process of the energy storage capacitor C3, the voltage at the two poles of the energy storage capacitor C3 will gradually decrease, and the current flowing through the resistor R8 to the first end of the resistor R9 will also gradually decrease. When the energy storage capacitor C3 is discharged At this time, the first end of the resistor R9 also becomes a low potential, so far, the shutdown process of the TV system is also ended.

In this embodiment, the mute control signal output by the entire mute auxiliary control circuit, that is, output to the mute control terminal of the speaker power amplifier circuit 300 and the mute control terminal of the earphone operational amplifier circuit 400 can be selected by selecting a resistor R9 with a specific resistance value. The level signal can meet the requirements of the TV system.

The embodiment of the utility model also provides a TV set, which includes a main control chip 200, a speaker power amplifier circuit 300, an earphone op-amp circuit 400, a DC power supply 500, and a mute auxiliary control circuit 100. control chip 200, loudspeaker power amplifier circuit 300, earphone operational amplifier circuit 400 and DC power supply 500 are connected, and mute auxiliary control circuit 100 includes:

The power supply terminal is connected to the output end of the DC power supply 500, and the output end is connected with the mute control end of the speaker power amplifier circuit 300 and the mute control end of the earphone operational amplifier circuit 400 at the same time, and generates the first mute control signal when the TV is powered on and powered off. Mute control signal generation unit 101;

The power supply terminal is connected to the output end of the DC power supply 500, and the input end and the output end are respectively connected with the general-purpose I/O port of the main control chip 200 and the input end of the first mute control signal generation unit 101. When the TV is working normally, according to The level signal output by the main control chip 200 generates the second mute control signal generation unit 102 corresponding to the mute control signal.

In the embodiment of the present invention, by adopting the mute auxiliary control circuit including the first mute control signal generating unit and the second mute control signal generating unit, it is possible to realize mute when the TV is powered on, powered off, and the TV is working normally and the user needs to When functioning, the mute control signal is stably output to realize the mute control of the speaker power amplifier circuit and the earphone op-amp circuit, and the circuit structure of the whole mute auxiliary control circuit is simple, which effectively reduces the cost, thereby solving the problem of mute provided by the prior art. The circuit has the problems of complicated circuit structure and high cost.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included in this utility model. within the scope of protection of utility models.

Claims (8)

1. the quiet auxiliary control circuit of a television set is connected with main control chip, loud speaker power amplifier, earphone discharge circuit and the DC power supply of television set, and described quiet auxiliary control circuit comprises:

The output of the described DC power supply of power supply termination, output is connected with the quiet control end of described loud speaker power amplifier and the quiet control end of described earphone discharge circuit simultaneously, generates the first quiet control signal generation unit of quiet control signal when television set powers on power down;

The output of the described DC power supply of power supply termination, input is connected with the universaling I/O port of described main control chip and the input of the described first quiet control signal generation unit respectively with output, when television set works, generate the second quiet control signal generation unit of corresponding quiet control signal according to the level signal of described main control chip output.

2. quiet auxiliary control circuit as claimed in claim 1 is characterized in that, the described first quiet control signal generation unit comprises:

Resistance R 1, positive-negative-positive triode Q1, storage capacitor C1, diode D1, diode D2, resistance R 2, resistance R 3, resistance R 4 and NPN type triode Q2;

The first end of described resistance R 1 is the power end of the described first quiet control signal generation unit, the base stage of described positive-negative-positive triode Q1 connects the first end of described resistance R 1, the emitter of described positive-negative-positive triode Q1 and the second end of described resistance R 1 are connected to the positive pole of described storage capacitor C1 altogether, the negative electrode of the negative pole of described storage capacitor C1 and described diode D1 is connected to the anode of described diode D2 altogether, the plus earth of described diode D1, the negative electrode of described diode D2 is the input of the described first quiet control signal generation unit, described resistance R 2 is connected between the negative electrode of the collector electrode of described positive-negative-positive triode Q1 and described diode D2, the base stage of described NPN type triode Q2 is connected with the negative electrode of described diode D2 and the first end of described resistance R 3 simultaneously, the second end ground connection of described resistance R 3, the grounded emitter of described NPN type triode Q2, the output of current collection the very described first quiet control signal generation unit of described NPN type triode Q2, described resistance R 4 are connected between the collector electrode of the first end of described resistance R 1 and described NPN type triode Q2.

3. quiet auxiliary control circuit as claimed in claim 1 is characterized in that, the described first quiet control signal generation unit comprises:

Resistance R 7, positive-negative-positive triode Q4, storage capacitor C3, diode D4, diode D5, resistance R 8 and resistance R 9;

The first end of described resistance R 7 is the power end of the described first quiet control signal generation unit, the base stage of described positive-negative-positive triode Q4 connects the first end of described resistance R 7, the emitter of described positive-negative-positive triode Q4 and the second end of described resistance R 7 are connected to the positive pole of described storage capacitor C3 altogether, the negative electrode of the negative pole of described storage capacitor C3 and described diode D4 is connected to the anode of described diode D5 altogether, the plus earth of described diode D4, the negative electrode of described diode D5 is the input of the described first quiet control signal generation unit, described resistance R 8 is connected between the negative electrode of the collector electrode of described positive-negative-positive triode Q4 and described diode D4, the first end of described resistance R 9 is the output of the described first quiet control signal generation unit and links to each other the second end ground connection of described resistance R 9 with the negative electrode of described diode D5.

4. quiet auxiliary control circuit as claimed in claim 1 is characterized in that, the described second quiet control signal generation unit comprises:

Resistance R 5, storage capacitor C2, NPN type triode Q3, resistance R 6 and diode D3;

The first end of described resistance R 5 is the input of the described second quiet control signal generation unit, the second end of described resistance R 5 and the positive pole of described storage capacitor C2 are connected to the base stage of described NPN type triode Q3 altogether, the equal ground connection of emitter of the negative pole of described storage capacitor C2 and described NPN type triode Q3, the collector electrode of described NPN type triode Q3 is connected with the first end of described resistance R 6 and the anode of described diode D3 simultaneously, and the second end of described resistance R 6 and the negative electrode of described diode D3 are respectively power end and the output of the described second quiet control signal generation unit.

5. television set, it is characterized in that, described television set comprises main control chip, loud speaker power amplifier, earphone discharge circuit, DC power supply and quiet auxiliary control circuit, described quiet auxiliary control circuit is connected with described main control chip, described loud speaker power amplifier, described earphone discharge circuit and described DC power supply, and described quiet auxiliary control circuit comprises:

The output of the described DC power supply of power supply termination, output is connected with the quiet control end of described loud speaker power amplifier and the quiet control end of described earphone discharge circuit simultaneously, generates the first quiet control signal generation unit of quiet control signal when television set powers on power down;

The output of the described DC power supply of power supply termination, input is connected with the universaling I/O port of described main control chip and the input of the described first quiet control signal generation unit respectively with output, when television set works, generate the second quiet control signal generation unit of corresponding quiet control signal according to the level signal of described main control chip output.

6. television set as claimed in claim 5 is characterized in that, the described first quiet control signal generation unit comprises:

Resistance R 1, positive-negative-positive triode Q1, storage capacitor C1, diode D1, diode D2, resistance R 2, resistance R 3, resistance R 4 and NPN type triode Q2;

The first end of described resistance R 1 is the power end of the described first quiet control signal generation unit, the base stage of described positive-negative-positive triode Q1 connects the first end of described resistance R 1, the emitter of described positive-negative-positive triode Q1 and the second end of described resistance R 1 are connected to the positive pole of described storage capacitor C1 altogether, the negative electrode of the negative pole of described storage capacitor C1 and described diode D1 is connected to the anode of described diode D2 altogether, the plus earth of described diode D1, the negative electrode of described diode D2 is the input of the described first quiet control signal generation unit, described resistance R 2 is connected between the negative electrode of the collector electrode of described positive-negative-positive triode Q1 and described diode D2, the base stage of described NPN type triode Q2 is connected with the negative electrode of described diode D2 and the first end of described resistance R 3 simultaneously, the second end ground connection of described resistance R 3, the grounded emitter of described NPN type triode Q2, the output of current collection the very described first quiet control signal generation unit of described NPN type triode Q2, described resistance R 4 are connected between the collector electrode of the first end of described resistance R 1 and described NPN type triode Q2.

7. television set as claimed in claim 5 is characterized in that, the described first quiet control signal generation unit comprises:

Resistance R 7, positive-negative-positive triode Q4, storage capacitor C3, diode D4, diode D5, resistance R 8 and resistance R 9;

The first end of described resistance R 7 is the power end of the described first quiet control signal generation unit, the base stage of described positive-negative-positive triode Q4 connects the first end of described resistance R 7, the emitter of described positive-negative-positive triode Q4 and the second end of described resistance R 7 are connected to the positive pole of described storage capacitor C3 altogether, the negative electrode of the negative pole of described storage capacitor C3 and described diode D4 is connected to the anode of described diode D5 altogether, the plus earth of described diode D4, the negative electrode of described diode D5 is the input of the described first quiet control signal generation unit, described resistance R 8 is connected between the negative electrode of the collector electrode of described positive-negative-positive triode Q4 and described diode D4, the first end of described resistance R 9 is the output of the described first quiet control signal generation unit and links to each other the second end ground connection of described resistance R 9 with the negative electrode of described diode D5.

8. television set as claimed in claim 5 is characterized in that, the described second quiet control signal generation unit comprises:

Resistance R 5, storage capacitor C2, NPN type triode Q3, resistance R 6 and diode D3;

The first end of described resistance R 5 is the input of the described second quiet control signal generation unit, the second end of described resistance R 5 and the positive pole of described storage capacitor C2 are connected to the base stage of described NPN type triode Q3 altogether, the equal ground connection of emitter of the negative pole of described storage capacitor C2 and described NPN type triode Q3, the collector electrode of described NPN type triode Q3 is connected with the first end of described resistance R 6 and the anode of described diode D3 simultaneously, and the second end of described resistance R 6 and the negative electrode of described diode D3 are respectively power end and the output of the described second quiet control signal generation unit.

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