Parallel coupled standby power supplies providing plural outputs

• US 6,838,861 B2
• Filed: 12/18/2000
• Issued: 01/04/2005
• Est. Priority Date: 06/02/2000
• Status: Expired due to Term

• Current Assignee: InterDigital Madison Patent Holdings (InterDigital, Inc.)
• Original Assignee: Thomson Licensing SA (Vantiva SA)
• Inventors: Testin, William John
• Primary Examiner(s): Sterrett, Jeffrey
• Application Number:
  US09/739,198
• Publication Number:
  US 20020024327A1
• Time in Patent Office: 1,478 Days
• Field of Search: 323/267, 323/269, 323/272
• US Class Current: 323/267
• CPC Class Codes: G05F 1/577 for plural loads
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 1/008 Plural converter units for generating at two or more independent and non-parallel outputs, e.g. systems with plural point of load switching regulators
• CPC Class Codes: H02M 3/1563 without using an external clock H02M3/158 takes precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A power supply for a television apparatus comprises a source of energizing potential (5.2V) fed to first and second control transistors (Q26403, Q26404). The first control transistor outputs a first source, while the second control transistor outputs a second source. The two control transistors are controlled by a feedback type voltage regulator (U26404) so that the sources track each other. The feedback voltage regulator is controlled by the second source. A storage capacitor (C26466) is coupled to the first source through an isolating resistor (R26462).

Claims

1. A power supply for first and second standby loads, said first standby load being a memory for data retention, which requires energization for a substantial time period following a power loss;

a voltage regulator having an input coupled to a source of input power, and an output coupled to the control terminal of first and second regulating transistors;

the output terminal of said first regulating transistor coupled to said first standby load, and the output terminal of said second regulating transistor coupled to said second standby load; and

a storage capacitor coupled through a resistance to the output terminal of said first regulating transistor.

2. A power supply as defined by claim 1, in which said voltage regulator is a feedback type of voltage regulator.

3. A power supply as defined by claim 2, in which the feedback fed to said voltage regulator is taken from the output terminal of said second transistor.