The M62333/M62338 is an integrated circuit semiconductor of CMOS structure with 3 channels of built in D-A converters with output buffer operational amplifiers. The input is 2-wires serial method is used for the transfer format of digital data to allow connection with a microcomputer with minimum wiring. The output buffer operational amplifier employs AB class output circuit with sync and source drive capacity of 1.0mA or more,and it operates in the whole voltage range from Vcc to ground.