DC-DC Boost Converter using MC34063A

DC-DC Boost converter circuit constructed by using IC MC34063A, the MC34063A series is a monolithic control circuit containing the primary functions required for DC- to -DC converters.

Hence it requires minimum number of external components for step up, step down and voltage inverting operations.

Circuit Diagram

Construction and Working

This circuit is designed to give 12V/1.5A output from minimum 5V DC input main part of this step up DC-DC converter is IC MC34063A, it is capable of taking input from 3.0V to 40V and gives output current range upto 1.5A with Adjustable output Voltage and also it has current limiting possibility and low standby current.

MC34063A Pinout

Value of R1 and R2 Resistors are responsible for internal oscillating frequency and VR1 is takes control on efficiency because it is connected between output and internal comparator.

Here L1 is 100µH or you can make core coil with 30 turns of 22 AWG, the MBR340 schottky barrier rectifier gives pure DC at output.This circuit can be used for step up DC supply from batteries.


5 thoughts on “DC-DC Boost Converter using MC34063A

  1. i tried this circuit but i get fixed output which is 11.1v, can you please explain more to me how it works?


    1. MC34063A Serisi, DC-DC dönüştürücüler için gereken birincil işlevleri içeren monolitik bir kontrol devresidir. Bu cihazlar dahili sıcaklık kompanzasyonlu referans, karşılaştırıcı, aktif akım limit devreli kontrollü görev döngüsü osilatörü, sürücü ve yüksek akım çıkış anahtarından oluşur. Bu seri, minimum sayıda harici bileşenle Step-Down ve Step-Up ve Voltaj-Ters Çevirme uygulamalarına dahil edilmek üzere özel olarak tasarlanmıştır. Vout formülünü kullanın ve istenen çıkış voltajı için R1, R2’yi değiştirin.

  2. On Q1 I missed the pull-down resistor at base so Q1 will safe turn off. Reduce C2 will increase switching frequency so you can reduce size for L1. TIP31 for Q1 looks like to small for 1.5A output current, Q1 should be switching 3 to 5 times more than output current. I though there were a lot of mistakes in this circut, you should calculate the correct values by using the equations given by datasheet from the MC34063

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