Using a VCXO (Voltage-Controlled Crystal Oscillator) as a Clock (CLK) Generator

Abstract: A VCXO (voltage controlled crystal oscillator) is an oscillator whose frequency is determined by a crystal, but can be adjusted by a small amount by changing a control voltage. VCXO clock (CLK) generators have been used in various applications, such as digital TV, digital audio, ADSL, and STB. This application note provides the general structure for a VCXO CLK generator, key performance measurements, guidelines for PCB design, and a test setup for MAX9485, a VCXO CLK Gen chip for MPEG2 and AC-3 audio applications.