RF-DAC Datapath Mode (Gen 3/DFE) - 2.6 English

Zynq UltraScale+ RFSoC RF Data Converter v2.6 Gen 1/2/3/DFE LogiCORE IP Product Guide (PG269)

Document ID
PG269
Release Date
2024-05-30
Version
2.6 English

The RF-DAC digital datapath is designed to trade off performance, flexibility, and power consumption. The maximum sampling rate and usable output bandwidth rely on certain datapath configurations. Combining different function blocks, the following table lists all available RF-DAC datapath modes.

Table 1. Datapath Modes
Mode 1 Mode 1 Mode 2 Mode 3 Mode 4
Short Name Full Nyquist DUC IMR Low-pass IMR High-pass DUC-Bypass
IMR x2 OFF ON ON OFF
Mix-Mode OFF ON OFF ON OFF ON OFF ON
Usable Bandwidth (Fs) 0-0.45 0.55-0.95 0-0.2 0.8-0.95 0.3-0.45 0.55-0.7 0-0.45 0.55-0.95
Reconstruction Filter Low-pass Band-pass Low-pass Band-pass Low-pass Band-pass Low-pass Band-pass
  1. The maximum sample rate changes depending on modes; the Mode 1 supports lower maximum sample rate than others. See Zynq UltraScale+ RFSoC Data Sheet: DC and AC Switching Characteristics (DS926).
  2. Usable bandwidth in this table is indicative and for reference only.
  3. The maximum achievable RF-DAC rate in Mode 4 (DUC-bypass) is determined by the PL timing closure.
  4. IMR High-pass mode shifts the original signal frequencies and inverts the spectrum.

When Zynq UltraScale+ RFSoC Gen 1/Gen 2 suggest using the DUC with complete Nyquist zone or its bypass corresponding respectively to Mode 1 and Mode 4, the addition of Mode 2 and Mode 3 in Gen 3/DFE will allow you to go up to the maximum sampling rate of the RF-DAC including the use of DUC signal processing. This enables the best trade-off of performance and power consumption thanks to the DUC running at half-speed of the sampling rate and the additional IMR filter enabled in the RF-DAC subsystem.