The ADC1251 is a CMOS 12-bit plus sign successive approximation analog-to-digital converter. On request, the ADC1251 goes through a self-calibration cycle that adjusts for any zero, full scale, or linearity errors. The ADC1251 also has the ability to go through an Auto-Zero cycle that corrects the zero error during every conversion.

The analog input to the ADC1251 is tracked and held by the internal circuitry, so an external sample-and-hold is not required. The ADC1251 has an S#/H control input which directly controls the track-and-hold state of the A/D. A unipolar analog input voltage range (0 to +5V) or a bipolar range (-5V to +5V) can be accommodated with ±5V supplies.

The 13-bit data result is available on the eight outputs of the ADC1251 in two bytes, high-byte first and sign extended. The digital inputs and outputs are compatible with TTL or CMOS logic levels.