| Summary: | 碩士 === 華梵大學 === 電子工程學系碩士班 === 100 === As time advances, electronic products have emerged in recent years, some electronic products require a higher clock, but the nature clock generator - quartz can not provide higher frequency, so the value of phase-locked loop revealed, we can produce a higher frequency from a smaller frequency for circuit by the loop characteristics feature.
The phase lock loop extensive usage in various signal generator, so the phase lock loop is already the important nucleus electric circuit of each kind of electron product, in addition to wanting to design to match the frequency, the stability of frequency is also a very important object, we can use phase frequency detector, charge pump, loop filter and voltage control oscillator and frequency divider in the circuit to make the whole electric circuit reached stabilization. Because of the frequency divider makes the phase-locked loop have a frequency multiplication effect , the multiple was determine by the frequency divider to the divisor. In the third chapter, we use Pulse swallow frequency divider to switching the counter divisor size
to achieve the effect of multiple changes.
Each of the electronic product had more and more function and multi-element have disadvantage for product is too large, so we joined the concepts to make circuit design smaller. We use cycle-control delay unit (CCDU) in the circuit, reduce the value of loop filter by increases , thus reducing the area to make the product more in line with modern needs and
production profits.
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