Using multiple cores on SoC’s are a well accepted solution to improving performance without using as much power as scaling up frequency but each core is a digital circuit that needs to be driven by a clock. Global clock distribution networks are responsible for delivering a reference clock signal to local clock generators that generate local clocks for each core. Current clock distribution and generation circuits tend to consume a lot of power and don’t have a set phase relationship, creating a need for synchronizers that inherently have some latency that limits throughput. This work aims to present a self-adjustable clock generator that multiplies the reference frequency to allow for slower references, which reduces power in clock distribution, and periodically injects the reference frequency to better establish a phase relation between the reference and output frequency. The main focus of the design is on a multiplying delay-locked loop whose frequency is managed by a digital control circuit. The circuit generates 16 phases of 2GHz using a 500 MHz injected reference signal. The injection allows the phase error to reset with every injection.




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