IC 7805 12V To 5V 2A Boost Converter Circuit

Sometimes 7805 regulator is not enough, as it gives only around 1 amp current.

However, many projects need more current for example motors, relays, LED strips and logic boards together.

Therefore, we need a simple solution, so we used an external power transistor TIP42 with 7805 IC.

This transistor boosts output current with this the voltage regulation remains stable.

Thus, this circuit is very useful as it is with low cost and easy to build and also it protects 7805 from overheating.

Circuit Working:

Parts List:

The circuit uses IC 7805, input DC voltage is given to the circuit and this voltage comes in at Vin terminal.

Then capacitor C1 removes ripple and so input noise is less.

After that current goes through resistor R1 and this resistor controls base current.

Now transistor TIP42 starts ON and it gives extra current to the load.

At the same time 7805 controls voltage and output stays at fixed 5V.

Because transistor helps the load the IC 7805 works with less stress and so heat is reduced.

Finally capacitors C2, C3 and C4 filter noise and output becomes clean and voltage is stable.

Formula with Calculation:

The calculation as per the circuit is for :

Input Voltage for Vin = 12V

Output Voltage for Vout = 5V

Voltage Drop Across R1:

Vdrop = Vin – Vout
Vdrop = 12 – 5
Vdrop = 7V

Resistor Value: R1 = 4.7 ohm

Current Through R1:

I = V / R
I = 7 / 4.7
I = 1.48 amp

Power Dissipation of R1:

P = I x I x R
P = 1.48 x 1.48 x 4.7
P = 10.3 watt

So minimum resistor power rating is 10W

But we have used 15W for safer choice.

How to Build:

To build a IC 7805 12V To 5V 2A Boost Converter Circuit follow the below steps:

• First, gather all the parts as shown in circuit diagram.
• Then start with 7805 pin 1 Input connect to Vin 12V positive.
• Connect pin 2 common Ground.
• Pin 3 output connect to output terminal.
• Also connect capacitors C3 and C4 positive and negative to GND.
• TIP42 Transistor emitter connect to Vin positive.
• Collector connect to output line.
• Base connect to junction of resistor R1, C1 capacitor and input pin of IC.
• Capacitor C1 positive connect to resistor R1 one end and collector of transistor Q1.
• C1 negative goes to ground.
• C2 connect between input and ground.

Notes:

• Use heat sink for transistor TIP42.
• Use heat sink for IC 7805 also.
• Input voltage must not exceed 20V.
• Capacitors should be good quality.

Conclusion:

This IC 7805 12V To 5V 2A Boost Converter Circuit is very useful.

It increases current capacity of 7805 and at the same time voltage stays stable.

Also circuit is simple and its components are easily available with low cost.

Therefore, this design is perfect and is good for beginners and professionals.

This circuit is highly recommended for power projects.

References:

Datasheet IC 7805

Datasheet TIP42