Synthesizable Injection-Locked Phase-Locked Loop with Multiphase Interlocking Digitally Controlled Oscillator Arrays

Abstract

A synthesizable injection-locked phase-locked loop with multiphase interlocking digitally controlled oscillator arrays (SILPLL-IDCOS) is proposed. By doing interlocking of two digitally controlled oscillators (DCOs), the number of phase provided can be double and the oscillation frequency can be as fast as the original DCO. Moreover, it also adopts frequency tracking loop to isolate the injection path from the traditional PLL path in the ILPLL, so the race condition in the traditional ILPLL can be resolved. The chip has been designed and implemented in TSMC 40 nm GP 1P10M CMOS process technology. In the proposed synthesizable ILPLL, all logic cells and circuit components are using standard cell provided by foundry and our group. The total area of the synthesizable ILPLL core is only 0.01876 mm2 and provides 8 phase output. The post-layout simulated RMS jitter from a 5.024 GHz output frequency is 0.048 %UI. The total measured power consumption is 10.97 mW at 5.024 GHz output frequency and 78.5 MHz reference clock.