Transformerless AC to DC power Supply circuits
I often make small projects. However have problems to find a small power supply is not. The problem is not to find a small transformer, However it is big and heavy. Not suitable for my project. But I see in the small appliance production in China. Do not widely used a transformer. However like to use a capacitor replace. Which it smaller and lighter than a transformer. Today I collect these circuits, so you can select to use in required. Hopefully it will be useful to you. There are 4 circuits, as follows. (see below!)
Danger! Do not touch any part of these circuits. Because you may be hit by electric shocks.
(1.)Power Supply 9VDC no transformer
This is circuiut power supply 9VDC no transformer,It easy circuit and small size.
Volt output = Volt Zenerdiode. Output Current 100mA (min).
It easy circuit and small size. Power Supply 9VDC no transformer
You may know the reason that make power supply circuit have large-sized as a result , because transformer. Way this out be must not use. We use capacitor replace as a result work also well. In Power Supply 9VDC no transformer circuit . The this base equipment have zener diode perform heal voltage be stable or 9V DC Regulator. but kind this circuit be defective that current not tall sir. The detail is other , see in the circuit sir.
(2.) DC power supply not use transformer
Work cycle is C1 and R1 acts reduced AC Current Source to rectifier current is a DC Volt by bridge diode circuit which D1-D4 acts to change AC to DC with the C2 makes the filtering power DC to smoother will a zener diode acts to reduce voltage is equal to the number of volt zener diode and C3 will DCV voltage output that is more smooth.
(3.)Negative Volage Regulator 6V not use Transformer
If friends with look for Mini power supply 6V sizes. That give negative voltage. I begs for to advise this circuit. It has prominent small-sized point and light weight. Because do not use Transformer. But still can use current get 0.07Amp not exceed and when see the circuit. Think use Zener diode control voltage be stable that 6V and have transistor enlarge the trend equal to that want. And still systematically protect through the circuit or Shot Circuit Protect with Transistor as well. The detail is other , see in circuit picture has yes.
(4.) DC Regulator supply 15V non transformer
Friends at don’t like large-sized of a transformer. I begs for to advise 15VDC regulator power supply can give the trend current get low about 80mA not exceed. But enough will usable small-sized circuit has comfortablely. Think I uses Zener Diode be formed help maintain one’s position volt be stable , and use Transistor help enlarge current tallly increasingly. Make this circuit is usable well , But friends as a result must use the carefulness specially , because apply to the level voltage tall directly yes.