Amonolithicclock-recoverycircuitusedin622Mb/sopticalcommunicationsystemisdesigned,whichisbasedonthephase-lockedlooptheory,,andusesbipolartransistormodel.Itovercomestheshortcomingofclockrecoverymethodbasedonfilter,andimplementsmonolithicclock-recoveryIC.Thedesignedcircuitsincludephaedetector,voltage-controlledoscillatorandloopfilter.Amongthem,thevoltage-controloscillatorisamodifiedtwo-stageringoscillator,whichprovidesquadratureclocksignalsandpresentswidevoltage-controlledrangeandhighvoltage-controllingsensitivity.
