The AD977/AD977A is a high speed, low power 16-bit A/Dconverter that operates from a single 5 V supply. The AD977A has a throughput rate of 200 kSPS whereas the AD977 has a throughput rate of 100 kSPS. Each part contains a successive approximation, switched capacitor ADC, an internal 2.5 V reference, and a high speed serial interface. The ADC is factory calibrated to minimize all linearity errors. The AD977/AD977A isspecified for full scale bipolar input ranges of +- 10 V, +-5 V and +- 3.3 V, and unipolar ranges of 0 V to 10 V, 0 V to 5 V and 0 V to 4 V. The AD977/AD977A is comprehensively tested for ac param-eters such as SNR and THD, as well as the more traditional dc parameters of offset, gain and linearity.