Patent · US Expired

Data output buffer of semiconductor memory device for preventing noises

US5438545A · kind A · utility

100Cited by
5References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 23, 1994
Grant dateAug 1, 1995
Priority date
Expiry dateFeb 23, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/00361
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A data output buffer, which includes a data output driver which in turn includes a pull-up circuit (14) operating in response to a first signal and a pull-down circuit (I10) operating in response to a second signal, and a control circuit for sensing a current flowing into the pull-down circuit via a feed-back and controlling the slope of the second signal in accordance with the sensed current. The control circuit includes a sensing circuit (I13) for sensing current flowing into the pull-down circuit upon driving data, and the magnitude of noises generated at the actual ground line (GND.sub.1 +GND.sub.2) due to the current, a voltage adjustment circuit (I14) which operates in response to the output signal of the sensing circuit and thereby adjusts the gate voltage of the pull-down circuit. Thereby, the noises generated in the chip are repressed without affecting the operational speed of the chip.

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