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Throughflow converter - has transformer with prim. winding via which first controlled switch is at input DC voltage and two sec. windings with common base
Throughflow converter - has transformer with prim. winding via which first controlled switch is at input DC voltage and two sec. windings with common base
The power supply uses a transformer (TR) with one primary coil (LP) supplied with DC via a switch (S1) and two secondary windings (L1, L2). One terminal of each secondary winding is connected to a common (negative) point, the other ends of the windings being connected to respective rectifier diodes (D1, D2) and reservoir capacitors (C1, C2) to produce first and second output DC voltages (U1, U2). The first secondary winding circuit also includes a freewheeling diode (D3) connected between the rectifier diode cathode and the negative line and an energy storage coil (SDR) in series with the rectified output. Control circuits (RS1, RS2) vary, as a function of the two output voltages, the respective duty cycles of the primary winding switch and a second switch (S2) which connects together the cathodes of the rectifier diodes. The duty cycle of the second control circuit is set so that the second switch is synchronized with the first switch and switches on only after the first switch is turned off. -USE/ADVANTAGE : As a switching type DC-DC converter, such as a SMPS using a flyback DC-DC converter. The circuit configuration provides a compact and inexpensive switching power supply with two separate regulated output voltages having a high degree of independence. Since the switching frequency remains constant, components such as the transformer can be dimensioned accordingly.
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