Simple Variable Power Supply 0-15VDC / 1A

This is the very simple general purpose variable power supply capable of delivering 0-15V DC output with about 1A electric current. The power supply circuit has regulated output and can be used for most small electronic circuit application.

This power supply circuit is very simple in construction, finding materials, easy and low cost. The output voltage is stabilized and regulated in the range of 0V to +15 V, supplied with a maximum current of 1 A. The adjustment is done in potensiometer R2. The Q1 is a classic power transistor and needs to be mounted on heatsink, and a constantly heated when working in the area of the peak current. The type of transformer is standard and can be found easily the market. The 4 rectifier diodes 1N4007 can be replaced with a standard 1A bridge diode.

Parts List:

R1 = 56ohm 2W
R2 = 330ohm Linear Potensiometer
C1 = 2200uF/35V
C2 = 100uF/35V
C3 = 10uF/25V
C4 = 220uF/25V
C5 = 100nF
GR1 = 4 x 1N4007
Q1 = 2N3055
T1 = 220V@18V 1.5A
D1 = 18V 1.5W zener

Simple variable power supply 0-15VDC / 1A, schematic diagram source: otenet.gr

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