Digital Datapath

Synchronization of Signal Processing in Multiple RF Data Converter Subsystems (XAPP1349)

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1.0 English

The digital datapath includes the whole digital signal processing between the PL and the analog RF converters. The Zynq UltraScale+ RFSoC offers a specific set of tiles to enable multiple RFDC channels in a device. Each tile consists of multiple channels. All channels within a tile are intrinsically synchronized by design, but not deterministic from reset to reset. MTS will be needed to achieve this. Care should be taken to ensure the NCOs are reset appropriately when using the NCO in multiple channels in a tile.

The MTS mechanism works the same way across multiple tiles or multiple chips. All chips will align their sample stream on the rising edge of their own analog_sysref signal when the MTS API is called. The rising edge of each individual analog_sysref can also be used as a trigger to dynamically update the NCO or QMC in the digital datapath on the fly. As an example, the QMC might change the signal phase and this updated phase can be applied at the same time across multiple tiles using the analog_sysref as a trigger.