Inexpensive Variable Power Supply




Introduction: Inexpensive Variable Power Supply

About: Fun with Electronics


Simple Power supply from LM2596 assembled module.

Can give output up to 35V.

Range 1.25V - 35V

Current up to safe 2.5A

Designed with

1. 2 Banana jacks for output

2. 1 Ammeter connection + its output

3. 1 External Voltmeter Connection (Can be used for output also)

4. USB output via Ammeter connection

5. DC Input via USB or Barrel Connector

6. 5mm LED for indication

7. DC Power switch

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Step 1: Components Needed

1 x External 30V 3A Power Adapter

1 x Barrel connector female

2 x Female Usb

1 x 5mm LED with holder

1 x 1.2kohm Resistor

1 x Slide switch

1 x Small cabel gland

DC DC Buck converter LM2596 Module

Link -

Link -

DC Voltmeter

Link -

10 x Banana connectors Female

2 x 12 Channel Terminal strip (to be cut into desired channels and be looped)

(Here I have used 4 channels 4 pieces looped one end)

Step 2: Drilling and Cutting

Position the components accordingly as required

I used a Power plus Die grinder for various drilling.

Step 3: Glued Fitting

These components needs to be glued to stay firm in place.

USB Female

LED with holder

Slide switch

Step 4: Circuit

Self Explanatory


1. Ammeter jacks can be jumped to use the third Output jacks on the right.

2. Voltmeter on board will not display less than 4.5V. Use the Yellow jacks with external Multimeter in voltage mode.

Step 5: Assembled

All connections made and ready to test.

Step 6: Samples

1. Battery bank charged via USB with current Indication.

2. 5V Output

3. 12V Output

1 Person Made This Project!


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3 Discussions


4 years ago

very good...


5 years ago

How much current are you getting out of the circuit?


Reply 5 years ago

Upto 3A acc. to specs.
Reliable to use upto 2.5A.