The AD5624R/AD5644R/AD5664R， members of the nanoDAC? family， are low power， quad， 12-/14-/16-bit buffered voltage-out DACs. All devices operate from a single 2.7 V to 5.5 V supply and are guaranteed monotonic by design. The AD5624R/AD5644R/AD5664R have an on-chip reference. The AD56x4R-3 has a 1.25 V， 5 ppm/°C reference， giving a fullscale output range of 2.5 V; the AD56x4R-5 has a 2.5 V， 5 ppm/°C reference giving a full-scale output range of 5 V. The on-chip reference is off at power-up， allowing the use of an external reference; all devices can be operated from a single 2.7 V to 5.5 V supply. The internal reference is enabled via a software write. The part incorporates a power-on reset circuit that ensures the DAC output powers up to 0 V and remains there until a valid write takes place. The part contains a per-channel power-down feature that reduces the current consumption of the device to 480 nA at 5 V and provides software-selectable output loads while in power-down mode. The low power consumption of this part in normal operation makes it ideally suited to portable battery-operated equipment. The AD5624R/AD5644R/AD5664R use a versatile 3-wire serial interface that operates at clock rates up to 50 MHz， and is compatible with standard SPI， QSPI?， MICROWIRE?， and DSP interface standards. The on-chip precision output amplifier enables rail-to-rail output swing.