US 5,353,215 A · Tracking run/standby power supplies

Abstract

A power supply for a television apparatus, comprises a first source of unregulated DO run voltage operable only in a run mode of operation and a second source of unregulated DO voltage operable in a standby mode and in the run mode of operation. A first regulator responsive to the first source unregulated DO run voltage produces a first regulated voltage. A second regulator responsive to the second source of unregulated DO voltage produces a second regulated voltage. First and second integrated circuits are energized respectively by the first and second regulated voltages. At least one of the integrated circuits has a signal output coupled to a signal input of the other of the integrated circuits. A controller is operable in the run mode and responsive to variations of one of the regulated voltages for adjusting the other of the regulated voltages to follow the variations. Each of the regulators may comprise a series pass transistor and a control transistor coupled to a base of the series pass transistor. Each of the control transistors provides a control current. The controller can be responsive to both control currents for adjusting the regulated voltages to track one another. The control circuit may sum the control currents.

Claims13

Dependent claims

A power supply system, comprising:

an unswitched voltage source energized during first and second modes of operation;
first voltage regulating means energized by said unswitched voltage source for energizing a first variable load at a first regulated voltage level and generating a first control current which varies with said first variable load;
a source of a reference voltage level coupled to said first voltage regulating means for establishing said first regulated voltage level, said reference voltage level being biased by said first control current;
a switched voltage source energized only during said second mode of operation;
second voltage regulating means energized by said switched voltage source for energizing a second variable load at a second regulated voltage level and generating a second control current which varies with said second variable load;
and,
said source of said reference voltage level also being coupled to said second voltage regulating means for establishing said second regulated voltage level, said source of said reference voltage level also being biased by said second control current, each one of said first and second regulated voltage levels tracking variations of the other one of said first and second regulated voltage levels.

4 more elements

Dependencies are inferred from the claim text.

Tracking run/standby power supplies

Life of this patent

Tracking run/standby power supplies

Life of this patent

Abstract

Claims13