An 8-bit 200-MSample/s folding and interpolating ADC in 0.25 mm(2)
This article is presented to describe an area-efficient CMOS folding and interpolating analog-to-digital converter (ADC) for embedded application, which is fully compatible with standard digital CMOS technology. A modified MOS-transistor-only folding block contributes to a small chip area. At the input stage, offset averaging reduces the input capacitance and the distributed track-and-hold circuits are proposed to improve signal-to-noise-plus-distortion ratio (SNDR). An INL/DNL of 0.77 LSB/0.6 LSB was measured. An SNDR figure of 43.7 dB is achieved at 4 MHz input frequencies when operated at full speed of 200 MHz. The chip is realized in a standard digital 0.18 mu m CMOS technology and consumes a total power of 181 mW from 3.3 V power supply. The active area is 0.25 mm(2).
folding interpolating analog-to-digital converter cmos analog integrated circuits