Apparatus within an integrated circuit for automatically detecting a test mode of operation of the integrated circuit and selecting a test clock signal

摘要

An integrated circuit (IC) includes circuitry for generating a clock signal during both a normal mode of operation and a test mode of operation. During the normal mode, an input clock signal is delayed via a skew corrector. In test mode, an input test clock signal bypasses the skew corrector via a clock signal source selector. The clock signal source selector is controlled automatically by a mode detector that responds to the input clock signals to determine the mode of operation of the IC.