A 2 × 24 Gb/s Single-Ended Transceiver With Channel-Independent Encoder-Based Crosstalk Cancellation in 28-nm CMOS

This article presents a mode decomposition encoder-based crosstalk cancellation (EB-XTC) scheme with orthogonal quasi-transverse electromagnetic (quasi-TEM) wave transmission that improves signal integrity (SI) across a pair of closely coupled differential channels for low-cost single-ended multiple input multiple output (SE-MIMO) applications. It achieves a nearly 100% crosstalk-induced jitter (CIJ) reduction ratio while relieving the pressure of the equalizer without channel dependence. To verify the scheme, a SE transceiver (TRX) is implemented in 28 nm CMOS. It consists of an encoding transmitter (TX) with a reconfigurable fractional-spaced feed-forward equalizer (FS-FFE) and a decoding receiver (RX) with a continuous-time linear equalizer (CTLE). The proposed FS-FFE reduces the number of source-series-terminated (SST) driver slices while ensuring sufficient resolution, thus reducing the chip area overhead and extending the bandwidth by 40%. Validated with 4- and 10-in differential channels, the wire-bonding packaged TRX operates up to 24 Gb/s/p-i-n at a bit error rate (BER) <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\lt } 1{e} {-}12$ </tex-math></inline-formula> and compensates for up to −2 dB far-end crosstalk and 20 dB Nyquist loss with 2.9 pJ/bit energy efficiency.