MAX544

19-1088; Rev 3; 12/99 +5V, Serial-Input, Voltage-Output, 14-Bit DACs General Description The MAX544/MAX545 are serial-input, voltage-output, 14-bit digital-to-analog converters (DACs) that operate from a single +5V supply. They provide 14-bit performance (±0.5LSB INL and ±0.9LSB DNL) over temperature without any adjustments. The DAC output is unbuffered, resulting in a low supply current of 0.3mA and a low offset error of 0.6mV. The DAC output range is 0V to VREF. For bipolar operation, matched scaling resistors are provided in the MAX545 for use with an external precision op amp (such as the MAX400), generating a ±V REF output swing. The MAX545 also includes Kelvin-sense connections for the reference and analog ground pins to reduce layout sensitivity. A 16-bit serial word is used to load data into the DAC latch. The 10MHz, 3-wire serial interface is compatible with SPI™/QSPI™/MICROWIRE™, and it also interfaces directly with optocouplers for applications requiring isolation. A power-on reset circuit clears the DAC output to 0V (unipolar mode) when power is initially applied. The MAX544 is available in 8-pin plastic DIP and SO packages. The MAX545 is available in 14-pin plastic DIP and SO packages. o +5V Single-Supply Operation o Low Power: 1.5mW o 1µs Settling Time o Unbuffered Voltage Output Directly Drives 60kΩ Loads o SPI/QSPI/MICROWIRE-Compatible Serial Interface o Power-On Reset Circuit Clears DAC Output to 0V (unipolar mode) o Schmitt-Trigger Inputs for Direct Optocou...