Patent · US Expired

BiCMOS logic circuit with self-boosting immunity and a method therefor

US5140192A · kind A · utility

16Cited by
5References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 1, 1990
Grant dateAug 18, 1992
Priority date
Expiry dateAug 1, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/09448
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A BiCMOS logic circuit with self-boosting immunity comprises a resistor, first and second transistors, a switching portion, and a discharge portion. The resistor and first transistor bias the switching portion to first and second reference voltages, which may be equal. The second transistor is a bipolar transistor providing an output signal to a load. The switching portion couples the bias voltage provided by the resistor and the first transistor to the base of the second transistor in response to a true result of a logic operation on at least one input signal and couples the base of the second transistor to a second power supply voltage terminal in response to a false result of the logic operation. The discharge portion couples the output signal to a logic low or pulldown voltage in response to a false result of the logic operation. In one form, the logic operation is a logical inversion of an input signal. In this case, the switching portion may be provided by a P-channel MOS transistor having first and second current electrodes connected serially between the bias signal and the base of the second transistor, with a gate receiving the input signal.

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