Patent · US Expired

Method and apparatus for testing pin isolation for an integrated circuit in a low power mode of operation

US5561614A · kind A · utility

22Cited by
1References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 30, 1995
Grant dateOct 1, 1996
Priority date
Expiry dateJan 30, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F11/2733
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A low power mode of an integrated circuit (IC) 10 is tested via a test controller 50. The IC 10 is placed in a low power mode where a plurality of pins represented by the pins 82, 72, and 62 are isolated from the internal circuitry, such as CPU 30, via circuits 60, 70, and 80. It is difficult, if not impossible, to test the IC 10 when in a low power mode since all pins are isolated from external circuitry and all clocks are stopped. Therefore, in order to test the low power mode, the test controller 50 can be selectively taken-out of low power mode via a RESET IN signal while all other circuitry in the IC 10 remains in the isolated low power mode. Test controller 50 can then conduct logical low power internal testing of the IC 10 while it is in low power mode and isolated. This testing in done by communicating data via the DATA IN and DATA OUT pins in a serial scan chain manner.

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