Control pulse generator for switching control transistor - has two capacitors whose charge controls XOR=gate controlling switching transistor

摘要

A signal derived from a control deviation generates an impressed current (IIK1) which charges a capacitor (4) whose voltage is applied to the input of a Schmitt trigger (5), whose output is applied directly or through an amplifier (9) to the input of an XOR gate (10) and through a resistor (7, 8) to a second capacitor (6). The voltage from the latter (6) is applied to a seond Schmitt trigger (11) whose output is connected to the second input of the XOR gate (10). Capacitors (4, 6) are simultaneously charged and discharged in accordance with the timing cycle (T). XOR gate (10) output is connected directly or through an amplifier to the switching control transistor (25) and makes it conducting or blocked.