Temp. compensated circuit with controllable capacitive diode - has second diode of opposite polarity in series and uses series connection as tuner for oscillation circuit

摘要

The operating point of the controllable capacitive diode in the temperature compensated circuit can be adjusted by a variable control voltage, derived from a temperature dependent voltage divider. A dividing resistor, formed by a forward polarised compensation diode, is in series with the voltage divider output. - The compensation diode diffusion voltage should be identical to the capacitive diode (3"). - The capacitive diode is series connected to a second diode (3"') which is oppositely polarised. This series connection forms a tuning element of an oscillation circuit (3", 3"', 11), whose inductance (11) is in parallel with the diode series connection. The first capacitive diode is in series with an additional variable control voltage source (Uk'), the series connection being connected to the voltage divider output (5, 6).