Quartz crystal oscillator temp. compensation circuit - derives voltage from temp. sensor and applies it to capacitance diode after processing

摘要

The circuit comprises connected in series a temp. sensor, an AD convertor, a function generator and a device for generation of a control voltage for a capacitance diode in series with the quartz crystal. The function generator and the device for the control voltage generation consist of a one-from-N decoder (7) and an N-value voltage divider (8) controlled by it and between supply voltage and zero potential. Its output voltage is applied to the capacitance diode (3), which is coupled to the quartz crystal (2) with the oscillator (1) on the other side. The multi-valve voltage divider incldes a number of resistors in parallel, adjacent to a filter.