LM2596 Pinout

5 - ON / OFF 4 - Feedback 3 - Ground 2 - Output 1 - V IN GND

The LM2596 series of regulators are monolithic integrated circuits designed for step-down (buck) switching applications. They are capable of driving a 3-A load with exceptional line and load regulation. Available in fixed output voltages of 3.3 V, 5 V, and 12 V, as well as an adjustable output version, these regulators support an input voltage range of up to 40 V.

Datasheet