VCXO Basics | Cypress Semiconductor
VCXO, or Voltage Controlled Crystal Oscillators are wonderful devices - they function in feedback systems to pull the crystal operating frequency to meet a target closed-loop response while maintaining a clean clock output. They are essential when you begin to approach systems that require frequency tracking such as a Set Top Box tracking from Satellite or a Cable feed. There are many applications for a VCXO, in the end it all boils down for one system to accurately track another.
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