DC supply with switch=on current limiting - has resistor in connection from rectifier to switching regulator

摘要

The d.c. voltage supply has the a.c. supply (UE) applied to a rectifier (G1) via an inductance (L1). The rectifier connects in parallel with a capacitor (C1) and the output is coupled to a switching unit (SNT). This is organised as a primary switching regulator with four switches (S1-S4) and a capacitor (K) coupled to the primary of a transformer. Located between the rectifier and the capacitor is an attenuator resistor (R1), in parallel with a bridging switch operated by a control stage. The resistor limits the current during switch-on. USE/ADVANTAGE - E.g. for high-power radio or television transmitters. Provides protection against starting currents and also mains overvoltages.