Patent · US Expired

Content addressable memory cell with a bootstrap improved compare

US6301140A · kind A · utility

1Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 25, 2000
Grant dateOct 9, 2001
Priority date
Expiry dateOct 25, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C15/04
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A content addressable memory, CAM, cell wherein the only compare-transfer FETS used are NFETs. The gates of the NFET compare-transfer FETS are driven to a voltage above the positive power supply, VDD. By precharging the bitlines to the negative power supply voltage, GND, the gate of one of the compare-transfer NFETS is driven above VDD when a bitline transitions from a "low" value to a "high" value. The capacitance between the bitline being driven high and the gate of a compare-transfer NFET couples the gate higher than VDD. This bootstrapping technique improves the compare access time of a CAM. In addition, this technique reduces the capacitance on the bitlines resulting in faster read and write access times and reduces the physical size of the CAM.

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