The AD9755 is a dual， muxed port， ultrahigh speed， singlechannel， 14-bit CMOS DAC. It integrates a high quality 14-bit TxDAC+ core， a voltage reference， and digital interface circuitry into a small 48-lead LQFP package. The AD9755 offers exceptional ac and dc performance while supporting update rates up to 300 MSPS. The AD9755 has been optimized for ultrahigh speed applications up to 300 MSPS where data rates exceed those possible on a single data interface port DAC. The digital interface consists of two buffered latches as well as control logic. These latches can be time multiplexed to the high speed DAC in several ways. This PLL drives the DAC latch at twice the speed of the externally applied clock and is able to interleave the data from the two input channels. The resulting output data rate is twice that of the two input channels. With the PLL disabled， an external 2× clock may be supplied and divided by two internally. The CLK inputs （CLK+/CLK–） can be driven either differentially or single-ended， with a signal swing as low as 1 V p-p.