An optimal filter with optional resolution used in incremental ADC for sensor application

An optimal filter used in second-order incremental sigma-delta ADC (ISDADC) for infrared focal plane array (IRFPA) with optional resolution from 13 to 16-bit is proposed in this paper. When modulator and filter work together as a whole ADC, the optimal filter talked here presents superior performances in both resolution and power consumption than classic linear filter with the same incremental sigma-delta modulator (ISDM). Besides, this optimal filter has optional output resolution range from 13 to 16-bit, which makes it more flexible. The design was implemented by 0.18μm 6-metal CMOS process, the core area of circuit is 350×350 μm², and power consumption of the core circuit is no more than 71μW with 13-bit resolution.