Patent · US Expired

Method and apparatus for signal level conversion with clamped capacitive bootstrap

US4835420A · kind A · utility

18Cited by
16References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 17, 1987
Grant dateMay 30, 1989
Priority date
Expiry dateNov 17, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/01812
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for converting input signals at one predetermined logic level to output signals at corresponding different logic levels includes differential amplification of input signals with a first output of a differential amplifier connected for establishing a voltage level between voltage limits V.sub.cc and V.sub.ee at the output of an output driver in response to variations in amplifier output. A pull-down transistor has a collector connected to the output driver output, an emitter connected to the V.sub.ee voltage source, and a base capacitively coupled to the second amplifier output. In further aspects of the invention, a voltage clamp embracing a transistor with a base connected to receive a predetermined control voltage has an emitter connected to the pull-down transistor base and a collector connected to the V.sub.cc voltage source.

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