Patent · US Expired

Constant voltage power supply

US6927559B2 · kind B2 · utility

1Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 2003
Grant dateAug 9, 2005
Priority date
Expiry dateMar 4, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05F1/575
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Disclosed is a constant voltage power supply, which comprises an error amplifier VEA including a transistor M3, and a transistor M4 having the same ratio between channel width and channel length as that of the transistor M3. The gate and source of the transistor M4 are connected to the gate of a transistor M3 to form a current mirror circuit in conjunction with the transistor M3. Further, the drain of the transistor M4 is connected with a transistor M5 adapted to be switched in response to an external control signal Sg. For example, when the transistor M5 is in ON state, any signal amplification function of the transistor M3 is vanished away, and the gain of the error amplifier VEA is lowered. The circuit configuration for changing the gain of the error amplifier VEA makes it possible to strike a balance between high-speed response characteristic in an active mode and operational stability in a sleep mode, and reduce a circuit area required for being formed on an integrated circuit.

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