Application Note: Tutorial On Oven Controlled Crystal Oscillators (OCXOs)

If stability requirements are too stringent to be met by a basic crystal oscillator or temperature compensated crystal oscillator (TCXO), the crystal and critical circuits may be temperature controlled by an oven. The block diagram for a Vectron oven controlled crystal oscillator (OCXO) is similar to that for a Vectron TCXO except that the varactor diode and associated thermistor compensation network are deleted and the oscillator is instead temperature controlled by a proportionally controlled oven.