General Description

The BM2596(=MSP1250G) series of regulators are integrated circuits that provide all

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 MSP1250G series operates at a switching frequency of 150 kHz thus allowing smaller

sized filter components than what would be needed with lower frequency switching

regulators. Available in a standard 5-lead TO-220 package with 5 pins lead in one line

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 MSP1250G series.

This feature greatly simplifies the design of switch-mode power supplies.

Other features include a guaranteed ±2 tolerance on output voltage under specified input

voltage and output load conditions, and ±10 on the oscillator frequency. External

shutdown is included, featuring typically 80 μA standby current. Self-protection features

include a two stage frequency reducing current limit for the output switch and an over tem

perature shutdown for complete protection under fault conditions.

Features

※ 3.3V, 5V, 12V, and adjustable output versions (ADJ)

※ Adjustable version output voltage range, 1.25V to 37V±2 max over line and load

conditions

※ Available in TO-220 and TO-263 packages

※ Guaranteed 3A output load current

※ Input voltage range up to 40V

※ Requires only 4 external components

※ Excellent line and load regulation specifications

※ 150 kHz fixed frequency internal oscillator

※ TTL shutdown capability

※ Low power standby mode, IQ typically 80 μA

※ G means Pb free in MSP1250G

※ Uses readily available standard inductors

※ Thermal shutdown and current limit protection

Applications

※ Simple high-efficiency step-down (buck) regulator , CAR DVD electronic

※ On-card switching regulators , LCD-TV , LCD-monitor , ADSL

※ Positive to negative converter