Adjustable 0-35V 3Amps DC Power Supply

In this project we are designing 3Amps 0-35V Adjustable power using LM2576. It is Switching regulator. It has many benefits such as It does not require any Heat sink, You can give higher Input voltage at input.

The LM2576 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version.

Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator.

The LM2576 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in some cases no heat sink is required.

A standard series of inductors optimized for use with the LM2576 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies.

Other features include a specified ±4% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring 50 μA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.

Step 1 : Components Required 
1. LM2576
2. 100uH 3A Inductor
3. 1K Resistor
4. 1000uF Capacitor Qty.2
5. PBT2 Connector Qty. 2
6. 3.3K Pot

Step 2 : PCB and Circuit Development
Adjustable Power Supply Circuit Diagram:

Adjustable Power Supply PCB Layout:

Pin diagram of LM2576:

Step 3 : Download PCB Layout
1. Power Supply Layout pdf