Simple 6V to 12V boost converter circuit using BD679 transistors

In this post, I am going to show you the 6v to 12v boost converter circuit. Imagine you have a 6V battery. But you need to use 12V of load like LEDs.  How do? See in your store, has only a transistor and simple parts without IC.

Stop thinking to buy a new 6V battery.

You may use these components to easy to solve problems.

Some called 6 volts DC to 12 volts DC step-up converter circuit. But the output is low current.

How it works

Look at the circuit Diagram below.

Simple 6V to 12V boost converter circuit using BD679 transistors

Here is the step-by-step process.

This circuit includes Q1, Q2, R1, R2, R3, R4, R5, D1, C1, and C2. They are the astable multivibrator mode. And the output is a Square Wave in many frequencies of the positive pulse signal.

Read also: Transistor circuit works

Then, look at R6 limits current flowing come to the base of Q3 and collector of Q4.

In this condition, Q3 gets a bias current, it runs. In contrast, Q4 does not get a bias current, so it does not run.

While Q3 runs. The current can flow through L1, D2 to an output. And some current via ZD1, cause drop voltage at ZD1.

Which be output voltage and voltage this increase continually poverty voltage that equal to 12 the volt.

By have R7 be limit current already change come in the way pin B of Q4

make Q4 work be make Q3 stop bias.

Then make output voltage be 0 volts, but when positive pulse signal that made come to then change come to at R6 then make Q3 bias again.

And work character as before but there are many speeds than can make output that appear

can come out 12 volts all the time by having C3 perform in something current filter smoothly

before increasingly lead output voltage goes to be usable.

Parts you will need

0.25W Resistors, tolerance: 5%
R1, R4: 1.8K
R2, R3: 4.7K
R5: 1K
R6: 1.5K
R7: 33K
R8: 10K
C1, C2: 0.1uF 50V Ceramic or Mylar
C3: 470uF 25V Electrolytic
D1, D2: 1N4148
ZD1: 12V 0.5W Zener Diode
Q1,Q2, Q4: BC547, 0.4A 40V Transistors
Q3: BD679 NPN transistor
L1: 100uH-22ouH

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5 thoughts on “Simple 6V to 12V boost converter circuit using BD679 transistors”

  1. Kontaktadresse : Dieter Jesse
    Grudene 8e
    58644 Iserlohn
    Nordrein-Westfalen/ Sauerland
    I speak not so good English

    Ist auch ein deutschsprachiger Kollege bei Euch dabei ?

    • Hello dieter jesse,

      Thanks for your visit to my site.

      Also, my English is so poor. I have used Google Translate. It is really good for me.

      No, We do not have who knows Germany. But I use google translate, I can understand what you said.

      Thus, what do you want? Can we help? Do not wait, tell us, our friend.


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