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A 40 Gb/s serial link interface is presented that includes four lanes of transceiver optimized for chip-to-chip communication while compensating for 20 dB of channel loss. Transmit equalization consists of a 2-tap feed-forward equalizer (FFE) while receive equalization includes a 2-tap FFE using a transversal filter, a 3-stage continuous-time linear equalizer with active feedback, and discrete-time equalizers consisting of a 17-tap decision feedback equalizer (DFE) and a 3-tap sampled FFE. The receiver uses quarter-rate double integrate-and-hold sampling. The clock and data recovery (CDR) unit uses a split-path CDR/DFE design which facilitates wider bandwidth and lower jitter simultaneously. A phase detection scheme that filters out edges affected by residual inter-symbol interference allows recovering a low-jitter clock from a partially-equalized eye. A fractional-N PLL is implemented for frequency offset tracking. Combining these techniques, the digital CDR recovers a stable 10 GHz clock from an eye containing 0.8 UI p-p input jitter and achieves 1-10 MHz of tracking bandwidth. The transceiver achieves horizontal and vertical eye openings of 0.27 UI and 120 mV, respectively, at BER = 10 -9 . The quad SerDes is realized in 28 nm CMOS technology. Amortizing common blocks, it occupies 0.81 mm^2 per lane and achieves 23.2 mW/Gb/s power efficiency at 40 Gb/s. [ABSTRACT FROM AUTHOR]

A 800 Mb/s to 3.2 Gb/s memory interface is designed that achieves 30% improved energy efficiency by eliminating idle mode power completely. The link is similar to a standard DDR architecture with the addition of a fast-lock DLL on the memory side that wakes up from 0 mW and locks within 3 clock cycles consuming 24 mW with residual timing error less than 33 mUI. Following initial lock, the DLL operates in a closed loop to compensate for V,T drift consuming 6 mW @ 1.6 GHz including a replica buffer. By incorporating an injection locked oscillator inside the loop, the DLL provides PLL like high frequency input jitter filtering, and corrects ±10% DCD without an additional duty cycle correction loop. [ABSTRACT FROM PUBLISHER]

This paper describes an asymmetric 6.4-Gb/s memory interface for a wide range of DIMM configurations for desktop and server applications. The link uses a fly-by quadrature forwarded clock to enable fast startup and power-mode transitions on the DRAM and per-bit timing adjustment on the controller to enable the high-speed signaling. Single-ended low-swing near-ground signaling (NGS) is introduced in order to minimize signaling power. Transmitter and receiver equalization are used on the controller, but not the DRAM, in order to save DRAM complexity and power. Architectural and circuit techniques are presented to address the complex signaling and timing environment encountered in the explored configurations. The implemented link achieves 6.4-Gb/s communication over a 3.5-in FR4 PCB trace with a dual-rank dual-in line memory module with better than 9.1-pJ/bit power efficiency for the entire chip. [ABSTRACT FROM PUBLISHER]

A 5 Gb/s source-synchronous signaling system was developed utilizing a new clock/data skew minimization technique. The method incorporates a transmit clock delay line and integrating receiver yielding an increased tolerance to high frequency transmit source jitter. The system has the potential to support rapid turn-on without the clock buffer latency of conventional source-synchronous systems. A second method to minimize clock distribution delays with embedded clocking via superposition of clock in the common-mode across two differential pairs was also explored. A test device was fabricated in TSMC's 40 nm LP CMOS process and performance measurements indicate substantial margin improvements, even when the matched source-synchronous system is subjected to realistic source SJ and independent PSIJ noise. Comparable performance was also achieved with embedded common-mode clocking with matched peak swings, indicating it as a potential solution for pin-constrained designs. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined a voltage and current analysis of magnetic amplifiers in switch mode power supply applications. Circuit description; Description of coupled magnetic amplifiers; Design and experimental results.