A 5.4-mW 4-Gb/s 5-band QPSK transceiver for frequency-division multiplexing memory interface

Abstract

This paper presents a novel self-equalized and skewless frequency-division multiplexing memory interface. To prove its feasibility, we have realized a 5-band QPSK transceiver in 40 nm CMOS to transmit up to 4 Gb/s through 10 orthogonal communication channels (each with 400 Mb/s) via on-chip TSV emulator with effective loading of 1 pF or 5-cm FR-4 PCB trace. With differential current-mode signaling, the transceiver consumes only 5.4 mW and takes only 80×100 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . A real-time flexible BER testing platform is established to prove that the BER of the transceiver is less than 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sup> .