Picture of the circuit:
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Circuit diagram:
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Transformer selection chart:
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Parts:
IC = LM317
P1 = 4.7K
R1 = 120R
C1 = 100nF - 63V
C2 = 1uF - 35V
C3 = 10uF - 35V
C4 = 2200uF - 35V
D1-D4 = 1N4007
Features:
- Just add a suitable transformer (see table)
- Great to power your projects and save money on batteries
- Suitable as an adjustable power supply for experiments
- Control DC motors, low voltage light bulbs, …
Specifications :
- Preset any voltage between 1.5 and 35V
- Very low ripple (80dB rejection)
- Short-circuit, thermal and overload protection
- Max input voltage : 28VAC or 40VDC
- Max dissipation : 15W (with heatsink)
- Dimensions : 52x52mm (2.1” x 2.1”)
Technical Specifications
- Input Voltage = 40Vdc max Transformer
- Output Voltage = 1.5V to 35Vdc
- Output Current = 1.5 Amps max.
- Power Dissipation = 15W max (cooled)
- It has not to be cooled if used for small powers. 28 Volt AC max is allowed for the input voltage.