A DAC/ADC-based Wireline Transceiver Datapath Functional Verification on RFSoC Platform

Abstract

This brief presents an RFSoC-based functional verification platform for a 2-lane pulse amplitude modulation (PAM) transceiver (TRX) datapath supporting 4-level PAM (PAM-4) and 8-level PAM (PAM-8). Digital-to-analog converters (DACs) and analog-to-digital converters (ADCs) existing on the ZU28DR RFSoC are used as digital front-ends of the transmitter (TX) and the receiver (RX), respectively. All digital equalization circuits and adaptation engines required for the modern > 112Gb/s DAC/ADC-DSP-based TRX datapath (excluding clock recovery) are implemented on the programmable logic (PL) running at 50 MHz, enabling real-time functional verification of the DAC/ADC-DSP-based serializer-deserializer (SerDes) operation. The register-transfer-level (RTL) design of the DSP can be directly used for the TRX silicon tape-out once the design is verified with the proposed RFSoC-based platform. The proposed system demonstrates a complete real-time functional verification of the TRX datapath, including the bit-error-rate (BER) test with the BER lower than 10−9 at 6.4Gb/s and 9.6Gb/s for PAM-4/8 symbols, respectively, with a channel loss of 18 dB at 1.6 GHz.