A novel all digital phase locked loop (ADPLL) with ultra fast locked time and high oscillation frequency

In this paper a new architecture for all digital phase locked loop (ADPLL) is proposed The new architecture is based on the ADPLL architecture proposed by Motorola in 1995 but modified in some block A new binary search decision scheme was used to accelerate the frequency acquisition process. It can reduce the chip area and increase the operating frequency. In this design, a 14-bit control word is used to control the digital control oscillator. The new type ADPLL has been designed and implemented by TSMC's 0-35 /spl mu/ IP4M CMOS process for 3.3V applications. The phase lock process takes 20-reference cycle, and the maximum frequency of the proposed ADPLL is about 820MHz.