Patent · US Expired

Output circuit and microcomputer

US6806747B2 · kind B2 · utility

3Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 20, 2002
Grant dateOct 19, 2004
Priority date
Expiry dateDec 20, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K17/223
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

When a control power source voltage becomes lower than an operation guarantee voltage level, the output of a start-up circuit assumes an H-level, a NOR gate produces an output shut-off signal of an L-level, and FETs are turned off. As the control power source voltage further decreases, the output shut-off control circuit loses stability in the operation. In this case, a resistor maintains the FETs in the OFF state due to its pull-down operation. As a result, the output of the output circuit is maintained in a high-impedance state over the whole range of control power source voltages lower than the operation guarantee voltage level.

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