Patent · US Expired

BICMOS input buffer circuit with integral passgate

US5289056A · kind A · utility

3Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1992
Grant dateFeb 22, 1994
Priority date
Expiry dateJun 12, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/0826
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A BICMOS input buffer circuit (20) incorporates an integral CMOS passgate circuit (P2,N2) between bipolar input (Q1) and output (Q3,Q4,Q5) transistors of the input buffer circuit. Latch enable inputs (LE) receive latch enable signals for operating the input buffer circuit and internal passgate in a transparent mode for passing data signals from the input (V.sub.IN) to the output (V.sub.OUT) and in a blocking mode for blocking data signals. The internal CMOS passgate circuit (P2,N2) is coupled into the input buffer circuit (20) to control nodes of the transistor output pullup (Q4,Q5) and pulldown (Q3) for controlling the conducting states of the respective transistor output pullup and pulldown to implement the blocking and transparent modes. A third passgate transistor (P3) may also be coupled between a control node (m1) of the transistor output pullup (Q4,Q5) and the low potential power rail (GND) for positive turn off of the output pullup. A dynamic power enhancement circuit (DPC) provides transient enhancement for the transition from the blocking mode to transparent mode.

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