Patent · US Expired

Programmable summing functions for programmable logic devices

US4912345A · kind A · utility

133Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1988
Grant dateMar 27, 1990
Priority date
Expiry dateDec 29, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/17712
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A programmable logic device includes a programmable logic array and an output logic macrocell. The output logic macrocell includes a user configurable summing function that has a first logic gate connected to receive a first plurality of product terms, a second logic gate connected to receive a second plurality of product terms and a third logic gate connected to receive the combination of the first plurality of product terms and a controls signal, a fourth logic gate connected to receive the combination of the second plurality of Product Terms and the control signal and a logic circuit connected to receive the output signals from the first, second, third and fourth logic gates and to provide a first logical combination when the control signal is at a first logic state and a second logical combination when the controls signal is at a second logic state.

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