Patent ID: 7317323

Claim:
A signal-test procedure for testing semi-conductor components, the signal test procedure, comprising: a) receiving a signal to be tested from an external connection of a semi-conductor component; b) coupling a reference signal at a particular voltage level from a further external connection of the semi-conductor component to a comparison node; c) performing a first comparison by comparing the signal with the reference signal; d) changing the voltage level of the reference signal a first time to a second particular voltage level after the first comparison is performed; e) performing a second comparison by comparing the signal with the reference signal at the second particular voltage level after changing the voltage level; f) decoupling the reference signal from the comparison node, then coupling an internal reference signal to the comparison node; and g) receiving a further signal at the external connection of the semi-conductor component; h) performing a third comparison by comparing the internal reference signal with the further signal.