A 4.96-μW 15-bit Self-Timed Dynamic-Amplifier-Based Incremental Zoom ADC

A 15-bit self-timed incremental analog-to-digital converter (ADC) for event-driven applications is presented. It is based on an asynchronous zoom ADC structure and a fully differential self-timed dynamic-amplifier (DA)-based integrator. Dynamic element matching (DEM) and chopping techniques mitigate the mismatch and noise. Measurements show that the ADC without oversampled clock achieves 93-dB SNR in a conversion time of 0.37 ms while consuming only 4.96- $\mu \text{A}$ current from a 1-V supply. This corresponds to a Schreier FoM of 177.3 dB. The 0.23-mm2 chip was fabricated in a standard 55-nm CMOS process.