BUILT-IN SELF-TEST SYSTEM FOR VLSI CIRCUIT CHIPS

摘要

A system (10) self-control logic incorporated in a circuit board (12) large scale integrated (LSI) for performing dynamic tests of the operation of the main logic function (14) comprises a control register (32) containing a series of static latches (150) connected to the serial transfer of control data and for generating control signals of the control system. A shift register input (36) connected to the control register (32) for performing serial transfer of control data and to the main logic function (14) for performing the parallel transfer of control data is formed a series arrangement of static scales. An output register (38) connected to the input register (36) for performing serial transfer of control data and to the main logic function (14) for performing the parallel transfer of control data is formed of a series arrangement of static scales (182). An enable signal and control synchronization is locked by a latch (78) and validation control and synchronization triggered by a system timing signal for generating timing signals of the input and output registers. A control strobe signal is blocked by a control sampling flip-flop (76) and sampled by a latch (80) and serves as a validation signal of the control register. The sampling hold signal and the control signal blocked validation and synchronization control are triggered by the system timing signal and serve as a control register of the synchronization signal. A multiplexer (40) output the control data decodes a selection signal generated by the control command register and provides thus represented control data to a spindle (60) for controlling data output.