LM2596SX-12

Product Summary

Simple high-efficiency step-down (buck) regulator
On-card switching regulators
Positive to negative converter
ote: ? Patent Number 5,382,918.

Parametrics

n 3.3V, 5V, 12V, and adjustable output versions
n Adjustable version output voltage range, 1.2V to 37V
± 4% max over line and load conditions
n Available in TO-220 and TO-263 packages
n Guaranteed 3A output load current
n Input voltage range up to 40V
n Requires only 4 external components
n Excellent line and load regulation specifications
n 150 kHz fixed frequency internal oscillator
n TTL shutdown capability
n Low power standby mode, I
Q
typically 80 μA
n High efficiency
n Uses readily available standard inductors
n Thermal shutdown and current limit protection

Features

The LM2596 series of regulators are monolithic integrated
circuits that provide all the active functions for a step-down
(buck) switching regulator, capable of driving a 3A load with
excellent line and load regulation. These devices are avail-able in fixed output voltages of 3.3V, 5V, 12V, and an adjust-able 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 LM2596 series operates at a switching frequency of
150 kHz thus allowing smaller sized filter components than
what would be needed with lower frequency switching regu-lators. Available in a standard 5-lead TO-220 package with
several different lead bend options, and a 5-lead TO-263
surface mount package.
A standard series of inductors are available from several
different manufacturers optimized for use with the LM2596
series. This feature greatly simplifies the design of
switch-mode power supplies.
Other features include a guaranteed± 4% tolerance on out-put voltage under specified input voltage and output load
conditions, and ± 15% on the oscillator frequency. External
shutdown is included, featuring typically 80 μA standby cur-rent. Self protection features include a two stage frequency
reducing current limit for the output switch and an over
temperature shutdown f