An All-Digital Clock and Data Recovery Circuit for Spread Spectrum Clocking Applications in 65nm CMOS Technology

Ching-Che Chung1,  Duo Sheng2,  Yang-Di Lin1
1National Chung Cheng University, 2Fu Jen Catholic University


In this paper, an all-digital clock and data recovery (ADCDR) circuit is presented. The proposed ADCDR can recover the data stream sent by a transmitter with a spread spectrum clock generator (SSCG). The proposed adaptive gain control scheme can automatically adjust the phase tracking gain by counting the consecutive identical digits (CID), and the time-to-digital converter (TDC)-based fast phase compensation can quickly compensate for a large phase error. The proposed ADCDR can tolerate input peak-to-peak jitter up to 130ps at 480MHz with the down-spread 10% modulation. In addition, the bit error rate (BER) is less than 10^(-12) with 2^(31-1) pseudo-random binary sequence (PRBS). The proposed ADCDR is implemented in a standard performance 65nm CMOS process with standard cells. The active area is 130um × 100um, and the power consumption is 1.13mW at 480MHz with the down-spread 10% modulation.