Timer in a circuit for converting a direct voltage into another direct voltage

摘要

The timer has a common capacitor (8) for defining both the switch-off time and the switch-on time of a switching transistor (1) . The common capacitor is charged via a first resistor (5) and discharged via a second resistor (6). Both branches are decoupled so that the discharge process is not affected by the resistance in the charging branch. A diode (4) is connected in series with the first resistance in the charging branch to decouple the two branches and to prevent the capacitor from discharging via the first resistance in the charging branch.