Introduction

The LM2596S is a step-down switching regulator capable of driving up to 3A load current with excellent line and load regulation. This module converts higher DC voltages to lower voltages with high efficiency (up to 92%).

Key Features

Technical Specifications

Pin Configuration

Terminal	Label	Description
1	IN+	Positive input voltage (4.5-40V)
2	IN-	Negative input/Ground
3	OUT+	Positive output voltage
4	OUT-	Negative output/Ground
5	ADJ	Voltage adjustment (adjustable version only)

Basic Connections

Output Voltage Adjustment

// For adjustable version:
// 1. Connect input power (4.5-40V)
// 2. Use a small screwdriver to turn the blue potentiometer
// 3. Measure output voltage with multimeter
// 4. Adjust until desired voltage is reached
// 
// Formula for output voltage:
// Vout = 1.23V × (1 + R2/R1)
// Where R2 is the variable resistor (potentiometer)

Advanced Features

// Recommended protection:
// - Add 100μF electrolytic capacitor at input
// - Add reverse polarity protection diode
// - Add fuse for high current applications

// For high current applications:
// - Add heatsink to LM2596 chip
// - Ensure proper ventilation
// - Derate current at high temperature

// Fixed voltage versions available:
// - LM2596S-3.3 (3.3V output)
// - LM2596S-5.0 (5V output)
// - LM2596S-12 (12V output)
// No adjustment needed for fixed versions

// For best efficiency:
// - Keep input voltage close to output
// - Use low ESR capacitors
// - Keep traces short and wide
// - Operate below 2A for continuous use

Troubleshooting