Patent · US Expired

Enhanced test circuit

US5084874A · kind A · utility

80Cited by
11References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 25, 1990
Grant dateJan 28, 1992
Priority date
Expiry dateJun 25, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/318541
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A test cell (12) provides boundary scan testing in an integrated circuit (10). The test cell (12) comprises two memories, a flip-flop (24) and a latch (26), for storing test data. A first multiplexer (22) selectively connects one of a plurality of inputs to the flip-flop (24). The input of the latch (26) is connected to output of the flip-flop (24). The output of the latch (26) is connected to one input of a multiplexer (28), the second input to the multiplexer (28) being a data input (DIN) signal. A control bus (17) is provided for controlling the multiplexers (22, 28), flip-flop (24) and latch (26). The test cell allows input data to be observed and output data to be controlled simultaneously.

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