Patent · US Expired

Power supply switching circuit and method

US7205808B2 · kind B2 · utility

5Cited by
3References
15Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJun 2, 2005
Grant dateApr 17, 2007
Priority date
Expiry dateJun 20, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J9/061
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A power supply switching circuit includes an input terminal (2) for receiving a signal from a motherboard, an output terminal (4) to output a control signal, a first Bipolar Junction Transistor (BJT) (5), and a second BJT (7). A base of the first BJT is connected to the input terminal via a base bleeder circuit. A collector of the first BJT is connected to a stand-by power supply terminal (10) via a collector resistor. A base of the second BJT is connected to the collector of the first BJT. A collector of the second BJT is connected to a system power supply terminal (12) via a collector resistor. The collector of the second BJT is connected to the output terminal. Emitters of the first and second BJTs are grounded.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.