It is well known that most methods of frequency generation have significant temperature dependencies.
Crystal oscillators are much more stable over temperature than integrated RC oscillators. However, for ultra-precise time and frequency generation, the tempco of the crystal can be mitigated by keeping it at a constant temperature.
CSS partnered with a leading defense provider to develop a crystal thermal controller to enable ultra-precise time and frequency generation.
Custom Solution from CSS
This custom ASIC incorporates the heating element, temperature sensor and error amplifier into one integrated circuit.
An internal DAC and EEPROM set the temperature. A 15V power FET acts as the heating element. The maximum current is programmable and stored in the EEPROM.