Integrated circuit has device for selecting either internal or external reference voltage as integrated circuit reference voltage at least partly depending upon whether it is in test or non-test mode

摘要

The integrated circuit (10) references signals to a reference voltage to determine their logic levels, is configured for connection to an external reference voltage and has test mode and non-test modes, a device for generating an internal reference voltage and a device for selecting either the internal or external reference voltage as the integrated circuit reference voltage at least partly depending upon whether it is in test or non-test mode. An Independent claim is also included for a method of selecting between an internal and an external reference voltage.