Patent · US Expired

Power supply voltage step-down circuitry

US6111395A · kind A · utility

10Cited by
4References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 9, 1999
Grant dateAug 29, 2000
Priority date
Expiry dateNov 9, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05F1/465
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Power supply voltage step-down circuitry comprises a control unit for enabling either a first voltage step-down unit or a second voltage step-down unit according to a control signal applied thereto, a voltage checking unit for checking whether or not the value of a voltage generated by a power supply is equal to or greater than a predetermined value, and for furnishing a checking result signal at a predetermined level when the value of the voltage generated by the power supply is equal to or greater than a predetermined value, and a switching unit for connecting either the power supply or an output of the first step-down unit with a receiver, such as a ROM, according to whether or not the checking result signal from the voltage checking unit is at the predetermined level. The voltage checking unit includes a Schmidt circuit that furnishes the checking result signal at a level corresponding to the value of an output of a checking unit for furnishing the output having a value corresponding to the power supply voltage.

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