The AD5663， a member of the nanoDAC? family， is a low power， dual， 16-bit buffered voltage-out DAC that operates from a single 2.7 V to 5.5 V supply and is guaranteed monotonic by design. The AD5663 requires an external reference voltage to set the output range of the DAC. The part incorporates a power-on reset circuit that ensures the DAC output powers up to 0 V or midscale （AD5663BRMZ-1） and remains there until a valid write takes place. The part contains a 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 powerdown mode. The low power consumption of this part in normal operation makes it ideally suited to portable， battery-operated equipment. The power consumption is 1.25 mW at 5 V， going down to 2.4 μW in power-down mode. The on-chip precision output amplifier of the AD5663 allows rail-to-rail output swing to be achieved. The AD5663 uses 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.