A MultiPhase TimetoDigital Converter Differential Vernier Ring Oscillator This paper reports the development of an adjustable, TimetoDigital Converter (TDC) based on two vernier Ring Oscillators (RO). The TDC aims to measure timing in Resistive Plate Chamber (RPC) detector for CMS experiment. Considering previous designs, the contribution from power supply noise and intrinsic transistor noise had been minimizing with differential stages and proper transistor sizing. To reduce the timing resolution and deadtime inherent to Vernier TDC architecture, as many Phase Detector (PD) as possible had been implemented. Such functionality permits to choose whether reducing the dead time or measuring redundantly the startstop time difference for an improved precision. The prototype TDC fabricated in a 130nm technology consumes 8.5 mW power under 1.2V supply. The measurement of this chip shown a timing accuracy of 5.48 ps at a timing resolution of 8 ps for the first data allowed by the first phase detection.

A wide range and high resolution twostep TDC for millimeterwave band ADPLL A twostep timetodigital converter operating at high frequency and acting as the PhaseFrequency Detector in millimeterwave ADPLL is presented. Coarse TDC is to cover the input dynamic range and pass the subsampled residue to Fine TDC for more accurate quantization. A Vernier FTDC architecture based on two 11stage ring delay chains has been proposed. A senseamplifier based arbiter is applied in FTDC, which can still work even if the time difference between the data and clock rising edges is less than 50fs, further breaking the bottleneck of resolution. Besides, a new adaptive resetting mechanism is used for arbiters and ring oscillators in FTDC. Implemented in 28nm CMOS technology, simulation results show that this twostep TDC can achieve a resolution of 0.5ps and cover 10 bit input dynamic range, wide enough to process input signals with frequencies exceeding 10GHz. The simulated DNL and INL of TDC is 0.42LSB and 1.38 LSB, respectively.