JPH1169261A - Power supply circuit for television receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply circuit in which leakage magnetic field generated by a commercial power transformer does not give adverse effects to a CRT, at the time of receiving a television signal. SOLUTION: A standby power relay 4 that turns on/off a commercial AC power supply to a commercial power transformer 2a of a standby power supply 2 is provided. At the time of remote control standby state, the standby power relay 4 is closed to activate the standby power supply 2 and at the time of receiving a television signal, the standby power supply relay 4 is open to stop the standby power supply 2, so as to supply required power from a main switching power supply 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply circuit suitable for a television receiver having a standby power supply for standby for remote control by a commercial power supply transformer.

[0002]

2. Description of the Related Art In recent years, the power supply circuit of a television receiver has been reduced in cost, size, performance and energy saving.
There is a strong demand for smaller, low-noise, high-efficiency, and high-safety devices, and various configurations have been proposed. Hereinafter, the configuration of a conventional power supply circuit will be described.

Conventionally, a power supply circuit for a television receiver having a standby power supply using a commercial power transformer for standby of a remote controller has a circuit configuration as shown in FIG. 3, for example. In FIG. 3, reference numeral 1 denotes a power supply plug, 2 denotes a standby power supply for standby of a remote controller including a commercial power supply transformer 2a, a rectifier diode 2b and a smoothing capacitor 2c, and 3 denotes a control circuit for performing various controls by a microcomputer or the like. A power switch for manual operation is provided at any part of a power line between the power plug 1 and the control circuit 3 via the standby power supply 2. Reference numeral 6 denotes a television comprising a primary rectifier diode 6a, a primary smoothing capacitor 6b, a switching power supply transformer 6c generally having a plurality of outputs, a switching element 6d, a switching controller 6e, rectifier diodes 6f and 6g, and smoothing capacitors 6h and 6i. A main switching power supply for reception, 7 a main power supply relay for turning on / off the main switching power supply 6, 8 a drive circuit for the main power supply relay 7, 9
Is an inrush current reducing resistor for limiting a rush current flowing when the main switching power supply 6 is turned on.

The operation of the power supply circuit for a television receiver configured as described above will be described.
During standby of the remote controller, the main power supply relay 7 is off, the main switching power supply 6 is not operating, and the commercial AC power from the power plug 1 is transformed by the commercial power transformer 2a in the standby power supply 2 and is transformed. The AC voltage is rectified by the rectifier diode 2b and smoothed by the smoothing capacitor 2c to output a DC voltage, which is supplied to the control circuit 3. The control circuit 3 mainly waits for a command to start the television receiver from the remote controller or the like when the remote controller is in standby, and when receiving the command to start, mainly controls to turn on the main power supply relay 7 to start up the main switching power supply 6. Perform a series of controls. When the drive circuit 8 is operated under the control of the control circuit 3 and the main power supply relay 7 is turned on, the commercial AC power is supplied to the main switching power supply 6 via the rush current mitigation resistor 9 and the primary rectifier diodes 6a and 1 The DC voltage rectified and smoothed by the next smoothing capacitor 6b is controlled and operated by the switching power supply transformer 6c and the switching element 6d by the switching control section 6e to transform the DC voltage into a high frequency AC voltage, and the transformed AC voltage is rectified. Generally, a plurality of DC voltages are output and rectified and smoothed by the diodes 6f and 6g and the smoothing capacitors 6h and 6i, and supplied to a television receiving circuit. The inrush current mitigation resistor 9 is a resistor inserted to suppress the peak of the current that rapidly flows into the primary smoothing capacitor 6b when the main power supply relay 7 is turned on from the off state. It protects the rectifier diode 6a and the like. When receiving a command to stop the television receiver from a remote controller or the like, the control circuit 3 performs a series of controls mainly for turning off the main power supply relay 7 to stop the main switching power supply 6. When the main power supply relay 7 is turned off by the drive circuit 8 under the control of the control circuit 3, the supply of the commercial AC power supply to the main switching power supply 6 is stopped, the supply of the DC voltage to the television receiving circuit is also stopped, and the remote control waits. State.

A television receiver having a remote control standby function can easily and quickly turn on and off the television reception function by a convenient remote control operation for the user, and it is necessary to keep the power consumption during the remote control standby mode small. There is. As a standby power supply for a light load during standby of the remote controller, a circuit configuration using the above-described commercial power supply transformer is generally used, the number of parts is small, it can be realized at relatively low cost, and the user can be away from the device for a long time. Some of them have high reliability and safety in the remote control standby state.

FIG. 4 shows the circuit configuration shown in FIG.
A resistor short-circuit power supply relay 12 and its drive circuit 13 are provided in parallel with the inrush current relaxation resistor 9. The rush current mitigation resistor 9 is a resistor inserted to suppress the peak of the rush current flowing when the main power supply relay 7 is turned on from the off state. However, when the main switching power supply 6 is in a normal operation state, Since power loss simply occurs, the resistor short-circuit power supply relay 12 is opened during the rush current flow and flows through the inrush current mitigation resistor 9, and the dedicated resistor short-circuit power supply relay 12 is provided during the normal current flow period. The power supply is reduced by short-circuiting.

[0007]

In such a conventional circuit configuration, a standby power supply using a commercial power supply transformer is always operated not only in a remote control standby state but also in a television reception state. In a CRT type television receiver, the trajectory of an electron beam is affected by a leakage magnetic field generated by a commercial power transformer, and the image fluctuates.
It is necessary to pay attention to interference such as flickering due to mislanding, reduce the leakage flux of the transformer, shield using a magnetic shield plate,
Since it is necessary to consider the installation at a distance from the T or in consideration of the angle of the transformer, the cost is increased.

[0008]

SUMMARY OF THE INVENTION In order to solve this problem, a power supply circuit for a television receiver according to the present invention comprises a standby power supply using a commercial power supply transformer for remote control standby and a main switching for television reception. A power supply, a standby power supply relay for turning the line on and off on a commercial AC power supply line to the commercial power transformer of the standby power supply is arranged, and the standby power supply is turned on to operate the standby power supply when the remote control is on standby. When receiving television, the standby power supply relay is turned off to stop the standby power supply, and all necessary power supply is performed from a main switching power supply.

According to the present invention, since the commercial power transformer operated during standby of the remote control is not operated during television reception, consideration is given to the influence of the leakage magnetic field generated by the commercial power transformer on the CRT. There is no necessity, which leads to cost reduction.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first invention of the present invention comprises a standby power supply using a commercial power transformer for standby for remote control and a main switching power supply for receiving television, wherein the commercial power transformer of the standby power supply is provided. A standby power supply relay for turning the line on and off is provided on a commercial AC power supply line to the standby power supply, the standby power supply relay is turned on when the remote control is on standby, and the standby power supply is operated, and when the television is received, the standby power supply relay is turned off. A power supply circuit for a television receiver in which the standby power supply is stopped and all necessary power supply is performed from a main switching power supply, and a commercial power supply transformer that operates during standby of a remote control does not operate when receiving television. Because of the occurrence of commercial power transformer Mode magnetic field does not need to the consideration of that an impact on CRT, an effect that leads to cost reduction.

According to a second aspect of the present invention, there is provided a standby power supply comprising a commercial power transformer, a rectifying diode for rectifying and smoothing the output of the commercial power transformer, and a smoothing capacitor.
A primary rectifier diode for rectifying and smoothing a commercial AC power supply, a primary smoothing capacitor, a switching power supply transformer controlled by a switching controller, a switching element, a rectifying diode for rectifying and smoothing the output of the switching power supply transformer, and a smoothing capacitor. A switching power supply, and a power supply plug to which commercial AC power is supplied is connected to the standby power supply via a standby power supply relay, and the power supply plug is connected to the main switching power supply via a main power supply relay and an inrush current reduction resistor. And a control circuit for controlling the standby power relay and the main power relay to be turned on and off, wherein the standby power relay is turned on and the main power relay is turned off when the remote controller is on standby. Operated by power supply from a standby power supply, the transition to the television reception state is controlled by the control circuit, the main power supply relay is turned on to operate the main switching power supply, and power supply from the main switching power supply is performed. The control circuit is made operable, the standby power supply relay is turned off, the standby power supply is stopped, and the transition to the remote control standby state is performed by controlling the standby power supply relay by turning on the standby power supply relay under the control of the control circuit. A television receiver power supply circuit for operating the control circuit by supplying power from the standby power supply, turning off the main power supply relay and stopping the main switching power supply, and Commercial power transformer Because never be operated when the television receiving and having the effect that the leakage magnetic field produced in the commercial power transformer there is no need to consider against an impact on CRT, also leads to cost reduction.

According to a third aspect of the present invention, a one-circuit c-contact (switching contact) type switching power supply relay is used as the standby power supply relay, and the standby power supply is connected so as to switch on the standby power supply and to short-circuit the inrush current reduction resistor. The television according to the second invention, wherein when the main switching power supply enters a normal operation state, the standby power supply is stopped and, at the same time, the rush current mitigation resistor on the commercial AC power supply line to the main switching power supply is short-circuited. It is a power supply circuit for the receiver, and it is not necessary to operate the commercial power supply transformer that operates when the remote control is on standby when receiving television, so it is necessary to consider that the leakage magnetic field generated by the commercial power supply transformer affects the CRT. Without
It leads to cost reduction and furthermore, one relay for standby power supply and one for short-circuiting rush current mitigation resistor.
By sharing a switching power supply relay of the contact (switching contact) type, power consumption can be reduced without increasing the number of components.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 is a configuration diagram of a power supply circuit for a television receiver according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a power plug, 2 denotes a standby power supply for standby of a remote controller including a commercial power supply transformer 2a, a rectifier diode 2b, and a smoothing capacitor 2c; 3, a control circuit for performing various controls by a microcomputer or the like; Standby power relay for turning on and off 2 and 5
Is a drive circuit for the standby power supply relay 4. In general, a power supply switch for manual operation is provided at any part of a power supply line from the power plug 1 to the control circuit 3 via the standby power supply relay 4 and the standby power supply 2. Provided. Reference numeral 6 denotes a primary rectifier diode 6a, a primary smoothing capacitor 6b, a switching power supply transformer 6c generally having a plurality of outputs, a switching element 6d, and a switching control unit 6.
e, rectifier diodes 6f and 6g, and smoothing capacitor 6
h and 6i, a main switching power supply for television reception, 7 is a main power supply relay for turning on and off the main switching power supply 6, and 8 is a main power supply relay 7.
Is a rush current reducing resistor for limiting a rush current flowing when the main switching power supply 6 is turned on.

The operation of the power supply circuit for a television receiver configured as described above will be described with reference to FIG. During standby of the remote controller, the standby power supply relay 4 is on, the main power supply relay 7 is off, the main switching power supply 6 is not operating, and the commercial AC power supply from the power supply plug 1 is connected to the commercial power supply transformer 2a in the standby power supply 2. The rectified diode 2b rectifies the transformed AC voltage and smoothes it with a smoothing capacitor 2c to output a DC voltage, which is supplied to the control circuit 3. The control circuit 3 waits for a start command of the television receiver from the remote controller or the like at the time of standby of the remote controller, and upon receiving the start command, activates the drive circuit 8 to start the main switching power supply 6 and activates the main power relay 7.
Is turned on, the commercial AC power is supplied to the main switching power supply 6 via the inrush current mitigation resistor 9, and the DC voltage rectified and smoothed by the primary rectifier diode 6a and the primary smoothing capacitor 6b is converted into the switching power transformer 6c and the switching. The element 6d is controlled and operated by the switching control section 6e to transform it into a high-frequency AC voltage, and the transformed AC voltage is converted into rectifier diodes 6f and 6f.
g and smoothing capacitors 6h and 6i for rectifying and smoothing, generally output a plurality of DC voltages and supply them to the television receiving circuit and simultaneously to the control circuit 3; 3 is made operable, the drive circuit 5 is controlled, the standby power supply relay 4 is turned off, and the standby power supply 2 is stopped. The inrush current mitigation resistor 9 is a resistor inserted to suppress the peak of the current that rapidly flows into the primary smoothing capacitor 6b when the main power supply relay 7 is turned on from the off state. It protects the rectifier diode 6a and the like. When receiving a command to stop the television receiver from a remote controller or the like, the control circuit 3 activates the drive circuit 5 to activate the standby power supply 2, turns on the standby power supply relay 4, and operates the standby power supply 2. Control circuit 3 that outputs DC voltage
And the control circuit 3 is made operable by the power supply from the standby power supply 2, the drive circuit 8 is controlled to turn off the main power supply relay 7, stop the main switching power supply 6, and supply a direct current to the television receiving circuit. The supply of the voltage also stops, and the remote controller enters a standby state. As described above, the standby power supply 2 is stopped when receiving television, and all necessary power is supplied from the main switching power supply 6, so that the commercial power transformer 2a that operates during standby of the remote control can operate when receiving television. Therefore, there is no need to consider that the leakage magnetic field generated by the commercial power transformer 2a affects the CRT, which leads to cost reduction.

(Embodiment 2) FIG. 2 is a configuration diagram of a power supply circuit for a television receiver according to a second embodiment of the present invention. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 2, reference numeral 10 denotes a one-circuit c-contact (switching contact) type switching power supply relay connected so as to switch on the standby power supply 2 and short-circuit the rush current mitigation resistor 9, and 11 denotes a drive circuit of the switching power supply relay 10. .

The operation of the power supply circuit for a television receiver configured as described above will be described with reference to FIG. 2, but the same operation as that described with reference to FIG. 1 will be omitted. When the remote controller is on standby, the switching power supply relay 10 is in the on state of the standby power supply 2 and the main power supply relay 7 is in the off state.
The main switching power supply 6 is not operating, and the standby power supply 2 outputs a DC voltage and supplies it to the control circuit 3. The control circuit 3 waits for a start command of the television receiver from the remote controller or the like at the time of standby of the remote controller, and upon receiving the start command, activates the drive circuit 8 to start the main switching power supply 6 and activates the main power relay 7. Is turned on, the commercial AC power is supplied to the main switching power supply 6 via the inrush current mitigation resistor 9, and the main switching power supply 6 generally outputs a plurality of DC voltages and supplies them to the television receiving circuit, and at the same time to the control circuit 3. The control circuit 3 is made operable by the power supply from the main switching power supply 6, the drive circuit 11 is controlled to switch the switching power supply relay 10 to the off side of the standby power supply 2, and the standby power supply 2 is stopped. The inrush current relaxation resistor 9 is short-circuited. The inrush current mitigation resistor 9 is a resistor inserted to suppress the peak of the current that rapidly flows into the primary smoothing capacitor 6b when the main power supply relay 7 is turned on from the off state. It protects the rectifier diode 6a and the like, and when the main switching power supply 6 enters a normal operation state, it is short-circuited by the switching power supply relay 10. When the control circuit 3 receives a command to stop the television receiver from a remote controller or the like, the drive circuit 1
1, the switching power supply relay 10 is turned on to turn on the standby power supply relay 2, the standby power supply 2 is operated, a DC voltage is output and supplied to the control circuit 3, and the control circuit 3 is supplied by the power supply from the standby power supply 2. And controls the drive circuit 8 to turn off the main power supply relay 7 to stop the main switching power supply 6,
The supply of the DC voltage to the television receiving circuit is also stopped, and the remote control enters a standby state. As described above, the standby power supply 2 is stopped during television reception, and all necessary power supply is performed from the main switching power supply 6, so that the commercial power transformer 2a that operates during standby of the remote control can operate during television reception. The leakage magnetic field generated by the commercial power transformer 2a
It is not necessary to take care of affecting the power supply, which leads to cost reduction. Further, when the main switching power supply 6 enters a normal operation state, the standby power supply 2 is stopped and the commercial power supply to the main switching power supply 6 is stopped. The rush current mitigation resistor 9 on the AC power supply line is short-circuited, and the standby power supply relay and the rush current mitigation resistor short-circuiting relay are connected to one single-circuit c contact (switching contact).
By sharing the type of switching relay, power consumption can be reduced without increasing the number of components.

[0017]

As described above, according to the present invention, since the commercial power transformer operated during standby of the remote controller is not operated during television reception, the leakage magnetic field generated by the commercial power transformer does not adversely affect the CRT. In addition, it is possible to provide a power supply circuit for a television receiver at a reduced cost.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a power supply circuit for a television receiver according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a power supply circuit for a television receiver according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional power supply circuit for a television receiver.

FIG. 4 is a configuration diagram of a conventional power supply circuit for a television receiver.

[Explanation of symbols]

 Reference Signs List 1 power plug 2 standby power supply 2a commercial power transformer 2b rectifier diode 2c smoothing capacitor 3 control circuit 4 standby power relay 5 drive circuit 6 main switching power supply 6a primary rectifier diode 6b primary smoothing capacitor 6c switching power supply transformer 6d switching element 6e switching control Unit 6f Rectifier diode 6g Rectifier diode 6h Smoothing capacitor 6i Smoothing capacitor 7 Main power relay 8 Drive circuit 9 Inrush current reduction resistor 10 Switching power relay 11 Drive circuit

Claims (3)

[Claims] A standby power supply for standby of a remote controller;
A main switching power supply for receiving television; and a standby power supply relay for turning on and off a commercial AC power supply line to the standby power supply. The standby power supply relay is turned on when a remote control is on standby. And a power supply circuit for a television receiver. 2. A standby power supply comprising a commercial power transformer, a rectifier diode for rectifying and smoothing the output of the commercial power transformer, and a smoothing capacitor; a primary rectifier diode and a primary smoothing capacitor for rectifying and smoothing a commercial AC power supply; and switching control. A switching power transformer, a switching element, and a main switching power supply including a rectifying diode for rectifying and smoothing the output of the switching power transformer, and a smoothing capacitor, and a standby power supply relay from a power supply plug to which commercial AC power is supplied. Connected to the standby power supply via the power supply plug, connected to the main switching power supply via the main power supply relay and the inrush current mitigation resistor from the power supply plug, and on / off controlled the standby power supply relay and the main power supply relay The standby power relay is turned on when the remote controller is on standby, the main power relay is turned off, and the control circuit is operated by power supply from the standby power supply. Under the control of a control circuit, the main power supply relay is turned on to operate the main switching power supply, the power supply from the main switching power supply enables the control circuit, the standby power supply relay is turned off, and the standby power supply is turned off. The power supply is stopped and the transition to the remote control standby state is performed by turning on the standby power supply relay to operate the standby power supply under the control of the control circuit, and enabling the control circuit to operate by the power supply from the standby power supply. Turn off the main power relay Television receiver power supply circuit so as to stop the main switching power supply Te. 3. A one-circuit c-contact (switching contact) type switching power supply relay is used as a standby power supply relay, and is connected so as to switch on a standby power supply and short-circuit a rush current mitigation resistor, so that a main switching power supply operates normally. 3. The power supply circuit for a television receiver according to claim 2, wherein in the state, the standby power supply is stopped, and at the same time, the rush current mitigation resistor on the commercial AC power supply line to the main switching power supply is short-circuited.