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Key Elements of an AC-DC Power Circuit

Looking for a complete, commercial off the shelf (COTS) AC-DC power supply circuit? You can find all the elements for miniature AC-DC power supplies available online and have them quickly shipped to your doorstep. But first, you need to know at least the basics about the various power circuit components you might need.

Your power supply unit (PSU) will consist of these basic elements: a transformer, rectifier, filter, and a voltage regulator. This kind of setup may be necessary with certain computer systems to prevent data loss during a power outage, and for setting up radio transmitters/receivers and any other electronic equipment that utilizes DC input-voltage.

Transformers

The transformers on the electric power pole near your home or business are sufficient for many in-building applications, but not for everything. To form a separate AC-DC circuit, you begin with a transformer unit.

The transformer will transfer electric power between a primary and a secondary winding without disturbing the frequency. It accomplishes three main goals: voltage step-ups, voltage step-downs, and isolation of primary from secondary circuits.

Rectifiers

The next step in the AC-DC conversion chain is the switch from AC to pulsating DC power. This is accomplished by rectifiers, typically diodes. You may need a half wave, full wave center tapped, or full wave bridge rectifier, depending on your situation.

Filters

After the rectifier has turned AC current into pulsating DC current, you now need to calm down those pulsations a bit. That’s where the filter comes in. Filters smooth out currents, preventing “ripples” that can damage your load or even your equipment, if the ripples are too “high.” This is a necessary safety device in any AC to DC circuit.

Regulators

Your filter won’t necessarily smooth out the DC current enough, which is why you need to add a final component to your AC-DC circuit: the voltage regulator.

To ensure a very, very steady DC output, regardless of what kind of input voltage you are experiencing at the moment, a regulator is necessary. There are two main types: series and shunt. The former regulates voltage by controlling input levels, while the latter accomplishes the same thing by diverting (shunting) away “extra” current.

Finally, there are also integrated circuit (IC) regulators that allow you to adjust your output voltage (though some IC regulators have fixed outputs).

Component Selection And Connection

Given the complexity of AC to DC power circuitry and the numerous varieties of every component part of the complete circuit, all but the most electronically astute will need a little assistance in selecting the best possible equipment for their particular application.

Further, you need the convenience of a wide selection of parts all in one location, which you can quickly peruse. PICO Electronics is a great solution: you can select from among literally thousands of items at their website, contact them for expert advice if need be to help in product selection, and get answers to any questions you may have about putting your full circuit together properly.

Plus, you can get your AC-DC power circuit devices customized to meet your exact needs and specifications. Without this kind of convenient, customizable experience, building and using your AC-DC power circuit would be much more challenging.