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Transformer-Isolated DC Power Supply

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Recipe #14 — transformer-isolated DC power supply

This page combines several earlier building blocks into one recognizable power supply.

Safety: the drawing is for understanding the blocks. Work involving mains wiring, transformer primary connections, fusing, grounding, insulation, and enclosure construction requires proper electrical safety practices.
TRANSFORMER-ISOLATED DC POWER SUPPLY AC source T1 isolating transformer BR1 4-diode bridge + − C1 filter load DC OUT
Follow the energy: AC source → transformer → bridge rectifier → filter capacitor → DC load.

Each block has one main job

T1: provides isolation and changes the AC voltage.

BR1: performs the four-diode full-wave rectification from the previous page.

C1: smooths the pulsating DC.

Notice the transformer symbol

The windings are shown as repeated coil loops with a core between them. A coil symbol should look like a winding, not like an AC sine wave.

Try these yourself

Which block provides electrical isolation? TRANSFORMER-ISOLATED DC POWER SUPPLY AC source T1 isolating transformer BR1 4-diode bridge + − C1 filter load DC OUT
The transformer separates the primary and secondary windings magnetically.
What does BR1 do?
BR1 represents the four-diode bridge rectifier from the previous lesson.
What is C1 primarily doing here?
The filter capacitor supplies current between rectified peaks and reduces output ripple.
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