MC34063 DC to DC Converter : Pin Configuration & Its Applications

An MC34063 DC to DC converter is also called a step-down or buck converter. This kind of converter is used to decrease the voltage when the current is increased from its supply to load. Here the regulated output voltage is lower as compared to the input voltage. There are different types of DC to DC converter ICs available in the market like LM2596, LM2576D2TR4, R1SE0505R, TSRN12433, LM2678TADJ, etc.


A DC to DC converter is one kind of electromechanical device or an electronic circuit, used to convert a DC source from one level of voltage to other. In this converter, the power levels mainly range from small to high. This article discusses MC34063 DC to DC Converter, pin configuration, working & its applications.

What is MC34063 DC to DC Converter?

A buck converter IC like MC34063 is a DC voltage converter that converts the voltage from high level to low level. These ICs are common elements in several applications like portable devices, satellites, hybrid energy systems, etc.

This MC34063A IC includes many functions which are mainly necessary for DC to DC converters. This series was specially designed to use in different applications like a step up, step down & inverting of voltage.

MC34063 DC to DC Converter
MC34063 DC to DC Converter

The main reason to use these converters in several applications is, they provide high efficiency, stable operation, greater reliability, various voltage and current levels from a similar PCB design. There are different kinds of DC to DC converters like a buck, boost, flyback, etc.

All these converters are also called switching regulators which are efficient highly like above 80% as evaluated to linear type regulators. While choosing a DC/DC converter, every designer must consider different factors like efficiency, the relation of I/O voltage, I/O isolation, highest o/p current, and range of i/p voltage.

Pin Configuration

The pin configuration of the MC34063 DC to DC converter is shown below. This IC includes 8-pins where each pin with its functionality is discussed below.

MC34063 IC Pin Configuration
MC34063 IC Pin Configuration

Pin1 (Switch Collector): This is the collector pin of the transistor which is also known as an o/p voltage pin.

Pin2 (Switch Emitter): This is an emitter pin of the transistor

Pin3 (Timing Capacitor): This pin is connected to a capacitor to decide the switching frequency

Pin4 (Ground): This pin is connected to the GND pin

Pin5 (Inverting Input of Comparator): This pin is used to set the o/p voltage

Pin6 (Vcc): Input voltage is given to this pin

Pin7 (Ipeak Sense): This pin is used to set the o/p current

Pin8 (Driver Collector): This is the collector pin of the transistor

Features & Specifications

The features and specifications of the MC34063 DC to DC converter include the following.

  • Input voltage supply ranges from 3V – 40 V
  • Standby current is low
  • DC to DC converter chip
  • O/P voltage can be adjusted from 1.25volts to 40volts
  • The operating frequency is 100 kHz
  • Max capacity of current is 1.5A
  • Switching frequency is100KHz
  • Collector current is 100mA
  • The internal reference is 2%
  • These ICs are Halogen, BFR, Pb−Free & are compliant with RoHS

Alternative DC-DC converters are LM2596, UCC25600, TC7660, and MCP16252 & Equivalent MC34063A DC to DC converters are CS51411, ACT4514, and TS2580.

Switching Regulator Circuit using MC34063 DC to DC Converter

The circuit diagram of the switching regulator with MC34063A DC to DC converter is shown below.
This circuit operates with a 12V stable battery. Even though, the input voltage can be changed 5V & 13V.
This circuit has maximum efficiency above 90% and this can be built with some basic electronic components very easily with less cost. This circuit can be built with an MC34063 dc to dc converter and a variable resistor like VR1 to control efficiency.

Switching Regulator Circuit with MC34063 IC
Switching Regulator Circuit with MC34063 IC

This IC is extremely helpful, so it can be used like different DC to DC converters like step-up step-down & the inverter including the functions of step-up/step-down. This IC is used in different devices like automobile chargers.

Circuit Working

The above circuit uses basic electronic components. In the circuit, the IC is powered by providing voltage to pin 6 like VCC & pin-4 to the GND terminal. A 100uF capacitor is used in this circuit to filter surplus noise from the power supply.

The Pin-2 of IC is connected to the base terminal of the transistor in the circuit like TIP31 to GND. In the circuit, pin-3 is connected to the timing capacitor like C2 & it will decide the circuit’s switching speed. Here pin-5 is an inverting terminal for the comparator

The non-inverting terminal’s voltage is from the interior voltage regulator is 1.25V. A resistor network is placed at the inverting terminal of the comparator. The gain of the comparator can be decided through the formula like VOUT = 1.25V * (1 + (R4/R3)). A potentiometer like VR1 is used for regulating the efficiency at 12V 600mA.

In this way, the above circuit has the boost functionality and this is a typical SMPS with the MC34063 IC to operate like a boost converter or step-up converter.

Where to use MC34063A/Applications

Generally, the IC like MC34063A DC-DC converter is used to design step down or Buck, step up or boost, and inverter circuits. This IC is an industry-standard, used to change the voltage in phone chargers in automobiles.

Since the regulation takes place throughout switching then it is extremely efficient as compared to linear circuits. So if you are looking to design a DC to DC converter with the above-mentioned specifications, then an MC34063 dc to dc converter is best.

The MC34063 IC was mainly designed to integrate into different converter-based applications like boost, buck otherwise voltage-inverter. It is used in the applications like portable chargers, circuits operated with a battery, medical devices, consumer electronics & measurement devices.

Thus, this is all about an overview of the MC34063 DC to DC Converter datasheet which includes its pin configuration, features, specifications, circuit, and applications. Generally, this DC to DC converter is one kind of electronic circuit, used to step down/up the voltage to obtain the preferred voltage. This converter is used in automobiles, solar grids, adaptors of laptops, etc. Here is a question for you, what is a boost converter?