Patent · US Expired

Substrate bias generating circuitry stable against source voltage changes

US5113088A · kind A · utility

36Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 7, 1990
Grant dateMay 12, 1992
Priority date
Expiry dateMay 7, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05F3/205
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Substrate bias generating circuitry for generating a substrate bias to be applied to the substrate of an integrated circuit. The circuitry includes an oscillator circuit for generating oscillator pulses having a predetermined frequency. A charge pump circuit has a capacitor and charges and discharges the capacitor in response to the oscillator pulses for generating the substrate bias. A substrate bias level sensing circuit is responsive to the voltage level of the substrate bias for outputting a control signal associated with the sensed voltage level. The level sensing circuit has a level holding subcircuit for holding the control signal in an enabled state at least for a predetermined duration which is four times as long as a period of time necessary for the charge pump circuit to complete a pumping operation. The pumping operation of the charge pump circuit is controlled by the control signal.

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