Patent · US Expired

Programmable logic device

US4963770A · kind A · utility

93Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 24, 1990
Grant dateOct 16, 1990
Priority date
Expiry dateJan 24, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/17728
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

In a programmable logic device having a plurality of programmable logic elements (PLEs) where each PLE includes a combinational logic circuit and a plurality of flip-flop circuits, input selector switches for selecting one of a plurality of input signals to be input into a flip-flop circuit are provided by which an output from a combinational logic circuit of its own PLE and an output from another PLE are made selectable. The output from the combinational logic circuit is also output independently of an output from a flip-flop circuit, so that either one of the outputs can be utilized by use of external programmble wiring. Further by selecting respective input terminals of each flip-flop circuit, an output signal from an adjoining flip-flop circuit is inputtable into another flip-flop circuit, so that the flip-flop circuits can be serially connected to each other. Additionally, the last flip-flop circuit of one PLE can supply an output signal to a first flip-flop circuit of an adjoining PLE by the selection of an input terminal which connects the adjoining PLEs through connecting wiring for specialized use, so that adjoining PLEs can be connected to each other without passing throu…

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