Patent · US Expired

Substrate generator

US4208595A · kind A · utility

27Cited by
11References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 1978
Grant dateJun 17, 1980
Priority date
Expiry dateOct 24, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB65G2209/04
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An FET substrate voltage generator circuit is disclosed for converting a single power supply and ground potential to a negative potential having an absolute value whose magnitude is greater than the power supply potential and applying that potential to the substrate of an integrated circuit upon which it is formed. The circuit dissipates less power per unit of current supplied by the circuit and occupies less space than do prior art circuits. The circuit applies the principle of voltage doubling to a first capacitor to achieve the desired voltage magnitude across a second capacitor and then applies the principle of a.c. coupling to that second capacitor connected through an impedance to the first capacitor, to achieve the desired polarity inversion for the substrate voltage to be generated. This circuit provides the current generating capacity necessary to drive the substrate to a negative voltage and sink the required current so as to maintain the substrate at an adequate negative bias.

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