Romesh Kumar Nandwana

Learn More
A hybrid phase/current-mode phase interpolator (HPC-PI) is presented to improve phase noise performance of ring oscillator based fractional-N PLLs. The proposed HPC-PI alleviates the bandwidth trade-off between VCO phase noise suppression and quantization noise suppression. By combining the phase detection and interpolation functions into XOR phase(More)
A phase interpolator (PI) based fractional divider is used to improve the quantization noise shaping properties of a 1-bit ∆Σ frequency-to-digital converter (FDC). Fabricated in 65nm CMOS process, the prototype calibration-free fractional-N Type-II PLL employs the proposed FDC in place of a high resolution TDC and achieves -102dBc/Hz in-band phase noise and(More)
A low power 14Gb/s transceiver using partially segmented voltage-mode driver, charge-based analog front-end, and low power clock and data recovery circuit that also minimizes clock distribution power is presented. Fabricated in a 65nm CMOS process, the transceiver achieves a power efficiency of 2.8mW/Gb/s and BER<10 while operating at 14Gb/s with 12dB(More)
A calibration-free ring oscillator based fractional-N clock multiplier using hybrid phase/current-mode phase interpolator is presented. Fabricated in 65nm CMOS process, the prototype generates fractional frequencies from 4.25GHz-to-4.75GHz with in-band noise floor of -104dBc/Hz and 1.5ps integrated jitter. The clock multiplier achieves power efficiency of(More)
Design techniques to improve energy efficiency of serial link transceivers are presented. Power consumption is reduced by using: 1) low-power clock generation, recovery, and distribution schemes; 2) charge-based circuits to implement analog front-end and samplers/flip-flops; and 3) a partially segmented voltage-mode (VM) output driver. An LC-oscillator(More)
A voltage mode transmitter employs pulse width modulation (PWM) based equalization of NRZ input data at 5 Gb/s and compensates 28 dB channel loss at 2.5 GHz. Fabricated in a 90 nm CMOS process, the proposed transmitter achieves a horizontal eye opening of 0.3UI with BER&lt;; 10<sup>-12</sup> and consumes only 16 mW power of which 2.5 mW is consumed by the(More)