8-bit TxDAC with 11 ns settling — what that buys the signal chain
The Analog Devices AD9704BCPZ is an 8-bit current-output DAC from the TxDAC® family, built with a current-source architecture that delivers a differential output. Its 11 ns typical settling time supports update rates into the 90 MSPS range, making it a fit for direct-digital synthesis, arbitrary waveform generation, and IF signal reconstruction in communications test equipment and software-defined radio transmit paths. The part accepts a parallel data interface and operates from separate 1.8 V and 3.3 V analog and digital supplies, keeping digital feedthrough off the analog rail.
Linearity that stays monotonic — INL/DNL ±0.03 / ±0.02 LSB
The ±0.03 LSB INL and ±0.02 LSB DNL figures are well inside the 0.5 LSB boundary that guarantees monotonicity. For an 8-bit converter, this means the output code never skips a step, which matters when the DAC is driving a modulator or a closed-loop control path where a non-monotonic transfer would cause a polarity reversal.
Package and supply — 32-LFCSP with dual 1.8 V / 3.3 V rails
Housed in a 32-lead LFCSP with exposed pad (5x5 mm body), the AD9704BCPZ needs a solid thermal via stitch under the paddle to pull heat out of the die. The dual supply scheme — 1.8 V for the digital core and 3.3 V for the analog output stage — is common in mixed-signal designs where the digital side runs from a low-voltage FPGA or ASIC interface while the analog swing stays at 3.3 V. The parallel data interface is 8 bits wide, so a single byte write per clock cycle; no serial latency to budget.
For BOM consolidation, the 12-bit AD9706BCPZ shares the same package and pinout — a drop-in upgrade if the system later needs more resolution.