The Fujitsu MB4053 is 6-channel, 8-bit, single-slope A/D converter subsystem designed to be used in a microprocessor based data control system. The MB4053 is single monolithic bipolar IC providing a 1 of 8 address decoder, 8-channel analog multiplier, sample and hold, constant current generator, ramp integrator and comparator in a 16-pin package. This A/D converter subsystems are suitable for a wide range of applications. The resolution required by an application can be obtained by arbitarily selecting a suitable integration time. Also zero offset and full-scale error corrections can be made automatically (auto-zero and auto-calibration) to minimize conversion error.