Patent ID: 8044735

Claim:
An oscillator circuit with an oscillator ( 112 , 212 ) comprising a toggle circuit ( 3 ), a Schmitt trigger ( 3 ) or a multi-vibrator or a relaxation oscillator or an amplifier circuit with hysteresis behavior, having an output (A) and an inverting input (E−), whereby the output (A) is connected to the inverting input (E−) via a feedback resistor (RR), the inverting input (E−) is connected to a first potential via a first oscillator capacitor (OC 1 ), the inverting input (E−) is also connected to a second potential via a second oscillator capacitor (OC 2 ) and via a control resistor (R var , RST, ST 1 , ST 2 , ST 3 , ST 4 ) that is series-connected to said second oscillator capacitor, and whose value can be adjusted or electrically controlled, so that a frequency (f) of the oscillator ( 112 , 212 ) can be varied by changing the value of the control resistor (R var , RST, ST 1 , ST 2 , ST 3 , ST 4 ), wherein the control resistor (R var , RST) is made up of a collector-emitter channel or a drain-source channel of a control transistor (ST 3 , ST 4 ), at whose emitter or source a control voltage (Uc) has been applied and whose base or gate is connected to a third potential (Q″), so that the second oscillator capacitor (OC 2 ) is connected to the control voltage (Uc) via the collector-emitter channel or the drain-source channel of the control transistor, and thus the control transistor is connected as a common base or common gate, and the frequency (f) of the oscillator ( 112 , 212 ) can be varied by changing the control voltage (Uc).