Patent attributes
A semiconductor chip including an embedded comparator is provided with an on-chip test circuit for the comparator. The test circuit includes an analog input unit which, during a test mode of the chip, produces a range of analog voltage signals that are applied to a first input of the comparator and a threshold voltage signal that is applied to a second input of the comparator. A switch control unit is provided to control the application of a predetermined sequential pattern of these 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. A digital measurement unit is provided to receive output signals from the comparator during the test period in response to the input patterns, to compare the output signals with the clock signal, and to measure and to store data relating thereto.
