Shaoxing Yuanfang Semiconductor Co., Ltd.

Nitesh Naidu

Srinath Sridharan

Ankit Seedher

Raja Prabhu J

Rakesh Kumar Gupta

Shivam Agrawal

Jeevabharathi G

Purva Choudhary

Clock generation circuit generating multiple divided signals satisfying respective desired offsets. A phase locked loop (PLL) is used to generate a PLL output having a frequency which is a desired multiple of that of a reference clock. The circuit divides the PLL output by a corresponding divisor to generate a corresponding divided signal, wherein each divided signal is offset from a common reference by at least an associated desired time offset. The common reference is timed with respect to the reference clock when the reference clock is available and with respect to a time reference signal otherwise. This arrangement is extended to use the internal time reference signal even for the cases where the reference clock is present by blocking the reference clock while the output systems across PLLs are aligned using the internal time reference signal to ensure desired offsets across different PLLs with a small uncertainty.

Generating divided signals from phase-locked loop (PLL) output when reference clock is unavailable

A phase-locked loop (PLL) provided according to an aspect of the present disclosure includes a phase detector, a low-pass filter, an oscillator, an output block and a phase locking block. The oscillator generates an intermediate clock and the output block generates each of successive cycles of a feedback clock on counting a pre-determined number of cycles of the intermediate clock. The phase locking block, upon detecting the PLL being out of phase-lock, controls the operation of the output block to obtain phase-lock in the PLL within two cycles of the input clock from the time of detection of the PLL being out of phase-lock.

Obtaining lock in a phase-locked loop (PLL) upon being out of phase-lock

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Bengaluru, India

Nitesh Naidu