Koninklijke Philips Corporation N.V.

Nxp B.v.

Ruediger Solbach

Friedrich Hapke

Tom Waayers

Andreas Glowatz

Hervé Fleury

Johan Corneel Meirlevede

Jozef R Poels

David P Price

Norbert Schomann

A method is provided for testing an integrated circuit comprising multiple cores, with at least two cores having different associated first and second clock signals of different frequencies. A test signal is provided using a clocked scan chain clocked at a test frequency (TCK). A transition is provided in a clock circuit reset signal (clockdiv_rst) which triggers the operation of a clock divider circuit () which derives the first and second clock signals (clk_xx, clk_yy, clk_zz) from an internal clock () of the integrated circuit. The first and second clock signals thus start at substantially the same time, and these are used during a test mode to perform a test of the integrated circuit. After test, the test result is output using the clocked scan chain clocked at the test frequency (TCK). Clocking hardware is also provided, and these provide at-speed testing which enables on the fly switching between a relatively slow tester driven clock for the shift modes and faster clocks generated by on-chip PLLs and divider circuits for the test mode.

IC testing methods and apparatus

In an arrangement for testing an integrated circuit comprising at least two circuit sections ( ) which in normal operation operate with at least two different clock signals, a minimal number of test runs for testing the integrated circuit is required because the integrated circuit to be tested is formed in such a way that each clock signal can be individually switched on and off during a test by test software provided in the arrangement, a software model of the circuit to be tested is provided in the arrangement, which software model comprises an X generator ( ) for those circuit components ( ) whose mode of operation is influenced by a plurality of clock signals and their skew behavior, which X generator is activated and supplies an X signal when more than one clock signal influencing the mode of operation of the circuit components ( ) during testing is activated, while, during testing, the test software initially activates all clock signals and evaluates test results for those circuit components ( ) for which no X signal appears in the software model ( ), and because for those circuit components ( ) for which an X signal appeared in the software model ( ) during testing with all clock signals, the test software performs a plurality of test runs in which each time only one or more of the clock signals influencing the mode of operation of the circuit component ( ) is/are activated and evaluates only those tests of the circuit components ( ) of the circuit for which no X signal appears in the software model ( ).

Arrangement and method of testing an integrated circuit

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Hamburg, Germany

Ruediger Solbach