DEVICE FOR STABLE OPERATION OF PHASE LOCKED LOOP OF OPTICAL TRANSFER SYSTEM

摘要

PURPOSE: A device for stable operation of phase locked loop (PLL) of an optical transfer system is provided to make a PLL used in an optical transfer system of 10GHz more stably operate. CONSTITUTION: In order to interface a negative signal of a phase detector in the PLL to a voltage controlled oscillator (VCO) (14) with a positive voltage tuning level, a forward diode D1 is connected between a low pass filter (10) and VCO (14), and reference voltage Vref is connected to a node N2 of diode D1's cathode through a resistor R5. This invention can control frequency response of broader band.