L7805 Circuit DIY: Adjustable Power Supply Step-down Module

The chip used in the picture is the most common regulator on the board L7805, we can use it DIY adjustable power supply buck module voltage

Things used in this project

Linear Regulator (7805) X1
Resistor, 200 ohm X1
Multi-Turn Precision Potentiometer- 1k ohms (25 Turn) X1

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Everyone should be familiar with the 78XX series of three-terminal regulator tubes. These 78XX series regulator tubes can often be seen in the circuit.

The L7805 can output 5V stably. Its pins are input, ground and output from left to right. As far as its parameters are concerned, the minimum input and output voltage difference is 2V; the maximum input voltage is 35V; the maximum output current is 1.5A;

In addition to stabilizing the output voltage, the L7805 can also be used to make a voltage regulating circuit.

The circuit we are going to make today looks like this:

L7805CV Circuit Diagram

Not only we only need a few simple components to make such a circuit, but it is somewhat similar to the method of using LM317 to make an adjustable circuit. However, compared to LM317, the L7805 three-terminal regulator tube is easier to find on the old circuit board.

The DIY steps are as follows:

Step 1: Bend the pins of the L7805 chip



L7805 chip


Step 2: Solder the L7805 chip and 200 ohm resistor, and cut off the excess wire


200 ohm resistor


Solder the L7805 chip and 200ohm resistor


cut off the excess wire

Step 3: Solder the 1K ohm potentiometer


1K ohm potentionmeter

Step 4: According to the circuit diagram, solder the remaining wires


solder the remaining wires


Step 5: That's all!


That's all

In practical applications, we should add filter capacitors to both the input and output ends.

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L7805 Circuit DIY: Adjustable Power Supply Step-down Module

Things used in this project

Story

The DIY steps are as follows:

Lily Hathaway