The quad, 8-bit DACs that operate from a single +3 to +5V supply or ±5V supplies. The AD7304 has a serial interface, while the AD7305 has a parallel interface. Internal precision buffers swing rail-to-rail. The reference input range includes both supply rails allowing for positive or negative full-scale output voltages. Operation is guaranteed over the supply voltage range of +2.7, +5.5 to ±5V consuming less than 9mW from a +3V supply. The full-scale voltage output is determined by the external reference input voltage applied. The rail-to-rail VREF input to DAC VOUT allows for a full-scale voltage set equal the positive supply VDD, the negative supply VSS or any value in between.