An analog-to-digital converter (ADC, A/D, A to D) is a device which converts continuous signals to discrete digital numbers. The reverse operation is performed by a digital-to-analog converter (DAC). [from Wikipedia]. ADCS7476 (datasheet), ADCS7477, and ADCS7478 are monolithic CMOS 12-, 10- and 8-bit analog-to-digital converters.