Convert AC to DC Power Supply
Convert AC mains voltage to stable DC with this DIY power supply circuit. Ideal for hobby electronics, microcontrollers, and small devices requiring a regulated DC output.

AC to DC power supply DIY
A DIY power supply circuit is an AC to DC power supply circuit that converts high voltage AC mains to low voltage DC that can be used in electronics projects. It has a smooth and safe DC output with the help of a transformer, rectifier, and capacitor.
bridge rectifier power supply
The DIY AC to DC Power Supply Circuit is a project aimed at converting the alternating current (AC) on the mains into a stable direct current (DC) voltage, which can then be used on electronic projects. The simple circuit comprises a step-down transformer, a bridge rectifier (diodes), a filter capacitor, and a voltage regulator, which is optional, so as to provide a smooth DC output. The high AC voltage is lowered by the transformer to a lower value. The bridge rectifier makes AC into pulsating DC and the capacitor filter eliminates ripples. To get an accurate voltage output, an adjustable LM317 or a regulator IC (such as 7805, 7812, or adjustable) may be used. The circuit is suited to introduction to electronics projects, microcontroller projects, battery charging, and battery powering of small devices. When dealing with mains AC voltage, proper fuses, safety measures, and insulation should be in use.
Work / Installation (Inputs → Outputs)
- AC Input → Mains supply (e.g., 220V AC).
- Step-down Transformer → Reduces voltage to desired level.
- Bridge Rectifier → Converts AC to pulsating DC.
- Filter Capacitor → Smooths voltage ripples.
- Voltage Regulator (Optional) → Provides stable DC output.
- Output → Usable DC voltage for electronic devices.
- Installation → Assemble on PCB/enclosure; use fuses and insulation for safety.
Testing & Final Adjustments
Once assembled, be careful when connecting the AC input and measure the DC output using a multimeter. Make sure that the output voltage is within the envisaged range. Raise adjustor (when necessary) to fine voltage. Positioning of check capacitors and connection of diodes to avoid failures. Load test using a small device or resistor to ensure stability and ripple reduction. Make sure that there is no overheating of the transformer, diodes, or regulator. Proper insulation and fuse protection should be used to avoid short circuiting or electric shock. Last testing produces a safe, stable and efficient AC to DC power supply that would be used in a hobby, microcontroller or small electronics project.
Frequently Asked Questions - Convert AC to DC Power Supply:
What is the purpose of this circuit?
To convert AC mains voltage to stable DC voltage for electronics projects.
Can I use it for microcontrollers?
Yes, suitable for 5V, 9V, or 12V DC microcontroller projects.
Do I need a transformer?
Yes, to step down AC voltage to a safe level.
Is a voltage regulator necessary?
Optional, but recommended for stable DC output.
Can I use it to charge batteries?
Yes, depending on the voltage and current rating.
Is it beginner-friendly?
Yes, basic knowledge of electronics is sufficient.
Do I need safety precautions?
Yes, handle AC voltage carefully with fuses and insulation.
What components are critical?
Transformer, bridge rectifier, capacitor, and regulator IC.
Can it supply multiple devices?
Yes, within the current rating of transformer and regulator.
Is it cost-effective?
Yes, uses readily available and inexpensive components.
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