Power supply circuit of a television receiver used in a automobile

• US 4,660,135 A
• Filed: 07/05/1985
• Issued: 04/21/1987
• Est. Priority Date: 07/05/1984
• Status: Expired due to Term

• Current Assignee: Gold Star Co., Ltd. (LG Corporation)
• Original Assignee: Gold Star Co., Ltd. (LG Corporation)
• Inventors: Lee, Yoon K.
• Primary Examiner(s): Wong, Peter S.
• Application Number:
  US06/751,885
• Time in Patent Office: 655 Days
• Field of Search: 323/266, 323/268, 323/271, 323/272, 323/284, 323/299, 363/20-21, 363/97, 358/190, 315/411, 455/343
• US Class Current: 363/21.04
• CPC Class Codes: H04N 5/63 Generation or supply of power specially adapted for television receivers

Abstract

A power supply circuit for a television receiver used in an automobile having either a 12 volt or 24 volt storage battery. The power supply circuit outputs a constant voltage whether connected from a storage battery of 12 volts or 24 volts thereby effecting stable operation of a TV set. A first constant voltage source is activated by an input of 12 volts and the output therefrom is boosted by a booster voltage circuit. A switch means is activated by an input of 24 volts and functions to disable the first voltage source means. A second voltage source means is activated by an input of 24 volts and outputs a constant voltage directly to a horizontal output circuit.

Claims

1. A power supply circuit of a TV receiver in a car using a storage battery of 12 volts or of 24 volts as a power source, comprising:

switching circuit means switched on at 24 volts and switching off a first constant voltage circuit which is turned on at 12 volts to output a first constant voltage;

a second constant voltage circuit turned on at said 24 volts to output a second constant voltage;

a horizontal drive circuit driven by said first and second constant voltage circuits to apply a horizontal oscillatory signal to a horizontal output circuit; and

a booster circuit boosting the output voltage from said first constant voltage circuit up to a booster voltage and then applying it to the horizontal output circuit through the primary coil of a high voltage transformer and also applying the output voltage from said second constant voltage circuit to the horizontal output circuit directly through the primary coil of said high voltage transformer, thereby making it possible to use the storage batteries of 12 volts and 24 volts in common.

2. A power supply circuit for a TV receiver in an automobile having a 12 volt or 24 volt DC power source, comprising:

first constant voltage means for outputting a constant voltage of a first magnitude;

second constant voltage means for outputting a constant voltage of a second magnitude higher than said first magnitude;

switching means responsive to a voltage of 24 volts from said DC power source for disabling said first constant voltage means;

said first constant voltage means being directly activated by a voltage of 12 volts from said DC power source;

said second constant voltage means being directly activated by a voltage of 24 volts from said DC power source;

booster circuit means for increasing the voltage outputted by said first constant voltage means including,

a primary winding of a high voltage transformer,

a center tap on said primary winding connected to said first constant voltage means,

capacitor means connected to one end terminal of said primary winding for increasing the voltage of said first constant voltage means;

said second constant voltage means also being connected to said one end terminal of said primary winding;

horizontal output means connected to the other end terminal of said primary winding for supplying AC power to said TV receiver;

horizontal drive means, connected to receive power from said first or said second constant voltage means, for providing an oscillation signal to said horizontal output means;

whereby said TV receiver is operable from either a 12 volt or 24 volt DC power source of said automobile.