Patent · US Expired

Integrated charge pump circuit with back bias voltage reduction

US5081371A · kind A · utility

119Cited by
6References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 7, 1990
Grant dateJan 14, 1992
Priority date
Expiry dateNov 7, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K2217/0018
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An integrated charge pump circuit with back bias voltage reduction includes one or more diode type voltage-multiplier stages, with each stage having a diode-connected NMOS transistor in place of the conventionally-used p-n junction diode. The transistors are formed within a P-type well, which forms the back gate of each transistor within the well, and the transistor threshold voltages are dependent on the potential of the P-type well. Performance of the charge pump circuit using NMOS transistors is enhanced by the use of a bias circuit which generates a bias voltage as a function of the output voltage generated by the charge pump circuit, and applies this bias voltage to the P-type well to minimize the back-body effects of the NMOS transistors. The bias circuit thus permits the construction of an integrated charge pump circuit with significantly lower MOS diode voltage drops than would otherwise be possible.

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