The AD5640 1 parts include an internal, 1.25 V, 5 ppm/°C reference, giving a full-scale output voltage range of 2.5 V. The AD5640 parts include an internal, 2.5 V, 5 ppm/°C reference, giving a full-scale output voltage range of 5 V. The reference associated with each part is available at the VREFOUT pin.

The parts incorporate a power-on reset circuit to ensure that the DAC output powers up to 0 V (AD5640) or midscale (AD5640-3) and remains there until a valid write takes place. The parts contain 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 power-down mode. The power consumption is 2.5 mW at 5 V, reducing to 1 ?W in power-down mode.

The AD5640 on-chip precision output amplifier allows rail-to-rail output swing to be achieved. For remote sensing applications, the output amplifier’s inverting input is available to the user. The AD5640 use a versatile 3-wire serial interface that operates at clock rates up to 30 MHz and is compatible with standard SPI®, QSPI™, MICROWIRE™, and DSP interface standards.