Synchronisable sawtooth or RC oscillator - uses feedback flip=flop for oscillator circuit receiving respective threshold voltages at data inputs and resetting input

摘要

The oscillator has a feedback flip-flop (FF) for the oscillator circuit (R1, R2, C) its data inputs (R, S) receiving respective threshold voltages (U1, U2) with a third threshold voltage (U3) between the first two threshold voltages fed to an AND-gate (A) combining it with a synchronising signal (SYNC). The output of the AND-gate is fed to the resetting input (RES) of the flip-flop. Pref. the three threshold voltages (U1...U3) are provided by a voltage divider (R3, R41, R42, R5), each voltage being fed to the flip-flop via respective comparators (K1, K2, K3). ADVANTAGE - Allows oscillator to be synchronised with external signal.