2.5 V to 5.5 V, 120 μA, 2-Wire Interface, Voltage-Output 8-Bit DAC

The AD5301/AD5311/AD5321 are single 8-/10-/12-bit, buffered, voltage-output DACs that operate from a single 2.5 V to 5.5 V supply, consuming 120 μA at 3 V. The on-chip output amplifier allows rail-to-rail output swing with a slew rate of 0.7 V/μs. It uses a 2-wire (I2C-compatible) serial interface that operates at clock rates up to 400 kHz. Multiple devices can share the same bus.

The reference for the DAC is derived from the power supply inputs and thus gives the widest dynamic output range. These parts incorporate a power-on reset circuit, which ensures that the DAC output powers up to 0 V 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 50 nA at 3 V and provides software-selectable output loads while in power-down mode.

The low power consumption in normal operation makes these DACs ideally suited to portable battery-operated equipment. The power consumption is 0.75 mW at 5 V and 0.36 mW at 3 V, reducing to 1 μW in all power-down modes.

Applications

* Portable battery-powered instruments

* Digital gain and offset adjustment

* Programmable voltage and current sources

* Programmable attenuators

* Buffered voltage output 8-bit DAC

* 6-lead SOT-23 and 8-lead MSOP packages

* Micropower operation: 120 μA at 3 V

* 2-wire (I2C-compatible) serial interface

* Data readback capability

* 2.5 V to 5.5 V power supply

* Guaranteed monotonic by design over all codes

* Power-down to 50 nA at 3 V

* Reference derived from power supply

* Power-on reset to 0 V

* On-chip rail-to-rail output buffer amplifier

* 3 power-down functions