AD9774,pdf datasheet (14-Bit,

Figure 22 shows a simplified block diagram of the AD9774. The
AD9774 is a complete, 4´ oversampling, 14-bit DAC that includes
two cascaded 2´ interpolation filters, a phase-locked loop
(PLL) clock multiplier, and a 1.20 Volt bandgap voltage reference.
The 14-bit DAC provides two complementary current
outputs whose full-scale current is determined by an external
resistor. Input data that is latched into the edge-triggered input
latches is first interpolated by a factor of four by the interpolation
filters before updating the 14-bit DAC. A PLL clock multiplier
produces the necessary internally synchronized 1´, 2´ and 4´
clocks from an external reference. The AD9774 can support
input data rates as high as 32 MSPS, corresponding to a DAC
update rate of 128 MSPS.