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Expired Canadian patentCanada

Finding faults in circuit boards

CA 1303236 C · Owner: Brown, David C. · Inventors: Brown, David C.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

of the Invention, The subject invention features diagnostic circuitry installed on one or more chips of a board. This diagnostic circuitry is constructed so that during a diagnostic interval it generates a diagnostic output signal if and only if it is supplied with normal voltages on service supply structures (such as ground, B+ supply, clock) distributing service voltages to devices on the board. The diagnostic output is connected to a diagnostic output pin of the chip which may also serve as one of the operating pins of the chip (such as a signal input pin). The receptacle for the diagnostic pin is connected on the board to a diagnostic interface at the periphery of the board.

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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted June 9, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 9, 2009.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJuly 21, 1989
GrantedJune 9, 1992
Term endedJune 9, 2009
Patent numberCA 1303236 C
Classification (IPC)G01R31/28 +2 more

Timeline

Timeline From CIPO dates

1990199219941996199820002002200420062008Application filedJuly 21, 1989Patent grantedJune 9, 1992Term endedJune 9, 2009

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.