Patent · US Expired

Fast swing-limited pullup circuit

US5619153A · kind A · utility

2Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 28, 1995
Grant dateApr 8, 1997
Priority date
Expiry dateJun 28, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/0013
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A pullup circuit having a limited voltage swing and fast pullup and pulldown times comprises a pullup structure, a pulldown structure and an internal node. The pullup circuit operates to limit the current of the pullup structure before the N-tree discharges the internal node, thereby reducing the pullup effect of the pullup structure to reduce fall time and power consumption. Then the pullup circuit maximizes the current of the pullup structure after the N-tree has pulled down the internal node to increase the pullup effect of the pullup structure to reduce rise time. As a result, the voltage of the internal node both charges more quickly when the N-tree becomes inactive and discharges more quickly when the N-tree becomes active.

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