An 8-bit 800-$muhboxW$1.23-MS/s Successive Approximation ADC in SOI CMOS

We report on an 8-bit successive approximation analog-to-digital converter (SA-ADC) that was designed and fabricated in 0.5-mum silicon on sapphire CMOS technology. The SA-ADC is capable of 32-MHz operation, providing 1.23-MS/s conversion rates, and consumes 800 muW at 3.3-V supply. The lack of substrate parasitic capacitances enables the use of small-area capacitors and reduces the noise coupling to the analog nodes. The circuits employ MOS transistors of different thresholds to optimize the performance and power dissipation of the system