DELAY LOCKED LOOP AND ASSOCIATED CONTROL METHOD

摘要

A control method for a delay locked loop includes: delaying an input signal to generate an internal signal; delaying the internal signal to generate an output signal; and selectively providing a reference clock signal or the output signal as the input signal according to the output signal and the internal signal.

主权项

1. A delay locked loop, comprising:
a programmable delay line, receiving an input signal to generate a first internal signal and an output signal, the output signal and the first internal signal having different phases; a control logic, receiving the output signal and accordingly providing a selection signal; a selection circuit, coupled to the control logic, selectively providing a reference clock signal or the output signal as the input signal; and a mask, coupled to the selection circuit, the control logic and the delay line, controlled by the first internal signal and the selection signal to determine whether to utilize the reference clock signal as the input signal.