The AD1851/AD1861 is a monolithic PCM audio DAC. The AD1851 is a 16-bit device, while the AD1861 is an 18-bit device. Each device provides a voltage output amplifier, DAC, serial-to-parallel register and voltage reference. The digital portion of the AD1851/AD1861 is fabricated with CMOS logic elements that are provided by Analog Devices' 2 m ABCMOS process. The analog portion of the AD1851/AD1861 is fabricated with bipolar and MOS devices as well as thin-film resistors.