Hi Guys! Welcome you on board. Happy to see you around. In this post today, I’ll detail the Introduction to LM2596.
LM2596 is a step-down voltage regulator, also known as buck convertor, mainly used to step down the voltage or to drive load under 3A. It carries the remarkable load and line regulation and is available in fixed output voltages including 3.3V, 5V, 12V. It also comes with a customized output version where you can set the output voltage as per your requirement.
Just stay with me for a little while, as in this post I’ll walk you through the Introduction to LM2596 covering the datasheet, pinout, features, and main applications of this tiny device.
Let’s jump right in.
Introduction to LM2596
LM2596 is a voltage regulator mainly used to step down the voltage or to drive load under 3A.
It is also known as DC-to-DC power converter or buck converter which is used to step down the voltage from its input supply to the output load. The current goes up during this voltage step down process.
LM2596 comes with a remarkable load and line regulation. It is available in both versions: fixed output voltage version with 3.3V, 5V, 12V, and customized output version where you can choose the output as per your requirement.
This regulator is incorporated with a fixed-frequency oscillator and an internal frequency compensation method.
Frequency compensation is applied by adjusting both phase and gain characteristics of the open-loop output to avoid oscillation and vibration in the circuit. This is achieved with the help of resistance-capacitance networks.
A minimum number of external components are required for this regulator that works at a fixed frequency of 150 kHz.
It is available in surface mount package TO-263 and standard 5-pin package TO-220.
Before you use this device for your electrical project, it’s wise to have a look at its datasheet that gives you an overview of the main characteristics of the component.
Click below to download the datasheet of LM2596.
The following figure shows the pinout diagram of LM2596.
The LM2596 comes with total five pins as follow:
Vin = I = this is the input supply pin interlaced with the input bypass capacitor to provide the switching current and to reduce voltage transients.
Output = O = this is the internal switch with voltage switches between (Vin – Vsat) and -0.5V. It comes with a duty cycle of Vout/Vin. The PCB copper area attached to this pin is used to minimize the coupling.
Ground = this pin is connected to the ground.
Feedback = I = this pin identifies the regulated output voltage for the feedback loop.
ON/OFF = I = this pin is used to shut down the voltage regulator circuit with input supply current reducing to 80uA. When the voltage on this pin goes below the threshold voltage of 1.3V, it turns on the buck converter. And when the voltage goes above the 1.3V, it turns off the converter. You can get rid of this shutdown feature by attaching the pin to the ground or leaving it open. In both cases, the regulator remains ON.
Fixed versions i.e. 3.3-V, 5-V, 12-V, and customizable output versions
Customizable output version with voltage range: 1.2-V to 37-V ±4% maximum over load and line conditions
Available in two packages including TO-263 and TO-220 packages.
Can drive load under 3A.
40 V is the input voltage range
4 external components are needed
Remarkable load and line regulations
Internal oscillator with a fixed frequency of 150 kHz
TTL shutdown capability
Comes with low power standby mode, commonly 80 µA
High efficient and readily available
Protection against thermal shutdown and current
LM2596 Power Ratings
The following table represents the absolute maximum ratings of regulator LM2596.
Absolute Maximum Ratings LM2596
Maximum Supply Voltage
SD/SS Input Voltage
Delay Pin Voltage
Flag Pin Voltage
Feedback Pin Voltage
Output Voltage to Ground
-65 to 150
While working with this component, make sure stresses don’t exceed the absolute maximum ratings, else they can permanently damage the component.
Plus, if stresses are applied for more than the required time, they can affect device reliability.
Used to step down voltage
Can drive load under 3A
Provide remarkable load and line regulation
That’s all for today. I hope you find this read helpful. If you’re unsure or have any questions, you can leave your query in the section below, I’d love to help you the best way I can. You’re most welcome to share your feedback and suggestions, they help us create quality content. Thank you for reading the article.
I am Syed Zain Nasir, the founder of The Engineering Projects (TEP). I am a
programmer since 2009 before that I just search things, make small projects and now I am sharing my
knowledge through this platform. I also work as a freelancer and did many projects related to
programming and electrical circuitry. My Google Profile+Follow