Patent ID: 7924044
Filing Date: 2011-04-12
Classification: G01R

Abstract:
1. A semiconductor chip comprising: an embedded comparator with first and second inputs and an output; an on-chip test circuit configured to test the comparator, the test circuit comprising an analog input unit configured to produce a range of analog voltage signals applied to the first input of the comparator during a test mode of the chip and a threshold voltage signal applied to the second input of the comparator; a switch control unit configured to control application of a predetermined sequential pattern of the analog voltage signals to the first input of the comparator in synchrony with a clock signal supplied to the switch control unit during a predetermined test period; and a digital measurement unit configured to receive output signals from the comparator during the predetermined test period in response to the predetermined sequential pattern, to compare the output signals with the clock signal, and to store data relating to the output signals and the comparison.