The AD5781 is a single 18-bit, unbuffered voltage-output DAC that operates from a bipolar supply of up to 33 V. The AD5781 accepts a positive reference input in the range 5V to VDD – 2.5 V and a negative reference input in the range VSS + 2.5 V to 0 V. The AD5781 offers a relative accuracy specification of ±0.5 LSB max, and operation is guaranteed monotonic with a ±0.5 LSB DNL max specification.
The part uses a versatile 3-wire serial interface that operates at clock rates up to 35 MHz and that is compatible with standard SPI®, QSPI™, MICROWIRE™, and DSP interface standards. The part incorporates a power-on reset circuit that ensures the DAC output powers up to 0 V and in a known output impedance state and remains in this state until a valid write to the device takes place. The part provides an output clamp feature that places the output in a defined load state.