A 8-bit 200 MS/s interpolating/averaging CMOS A/D converter

A 8-bit 200MS/s 4-2 interpolating A/D converter is presented. A novel input stage was developed to enhance the dynamic performance. Static performance is enhanced using the averaging technique. The chip has been fabricated in a standard 0.35 /spl mu/m CMOS process. An INL/DNL of 0.95/0.8 LSB was measured. An SNR figure of 44.3 dB was achieved at low frequencies: for a 30 MHz input signal an SNR figure of 43 dB was measured.