A TDC Based BIST Scheme for Operational Amplifier

This paper presents a time-to-digital converter (TDC) based built-in self-test (BIST) scheme for operational amplifier (Op Amp). The propagation delay exiting in the transient response of the Op Amp is monitored by the inverter based TDC, and converted into a digital code based on the referenced delay interval of the inverter used in the TDC, as a result, the digital code is finally employed to determine the test rsults. The circuit-level simualtion results of the proposed BIST syetem for a two-stage Op Amp are presented to demonstrated the feasility of the proposed BIST scheme with high fault coverage.