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Can a transformer be used to convert AC to DC?
We have already covered this type of AC to DC conversion, using Transformer in this article Cell Phone Charger Circuit. And yes, we can also convert the High voltage AC into Low voltage DC, without using the Transformer, this is called Transformerless power supply.
What kind of power supply do you need for a transformer?
Transformerless Power Supply. Generating Low voltage DC, from the 220v or 110v AC mains, is very useful and necessary in the field of electronics. Low voltage DC, like 5v, 6v, 9v, 12v, is used in electronics circuits, LED bulbs, toys and many household electronics items.
How does a Transformerless power supply circuit work?
Circuit is simple, Voltage dropping capacitor of 0.47uF is connected in series with Phase line of AC, this is a non-polarised capacitors so it can be connected from any side. A 470k ohm resistor is connected in parallel of Capacitor, to discharge the stored current in the capacitor when circuit is switched off, thus preventing from electric shock.
What’s the alternative to generating DC from AC mains?
So the alternative is to generate the DC from AC mains, for which there are many AC-DC adapters are available, but what circuitry they are using inside?
How does a transformer less power supply work?
This X rated capacitor is connected in series of Phase line of AC, to drop the voltage. This type of Transformer less power supply is called Capacitor Power Supply. As mentioned they are connected in series with phase line of AC to lower down the voltage, they are available in 230v, 400v, 600v AC or higher ratings.
How to avoid using a large DC transformer?
Some switching power supplies also avoid using the large power transformer by rectifying the mains voltage into a large DC voltage then use high frequency switching through a much smaller transformer. Again, though, “There be dragons here!”, and the DC voltages on the primary capacitors are nasty.