Offset cancellation for zero crossing based circuits

This work introduces a simple, background offset cancellation scheme for zero-crossing based circuits (ZCBC). The ZCBC architecture has been proposed as an alternative to op-amp based analog to digital converts (ADC) because it does not suffer from the gain, stability, and settling time trade off. However, offset remains as a challenge. This work demonstrates an input offset cancellation scheme that employs a replica circuit to measure and then subtract the offset. The cancellation method has been applied to annm.