Simple Switcher ® Integrated Circuit Chip 75V 3A Step Down Switching LM5576MHX

LM5576

SIMPLE SWITCHER® 75V, 3A Step-Down Switching Regulator

General Description

The LM5576 is an easy to use SIMPLE SWITCHER® buck regulator which allows design engineers to design and optimize a robust power supply using a minimum set of components. Operating with an input voltage range of 6 - 75V, the LM5576 delivers 3A of continuous output current with an integrated 170mΩ N-Channel MOSFET. The regulator utilizes an Emulated Current Mode architecture which provides inherent line regulation, tight load transient response, and ease of loop compensation without the usual limitation of low-duty cycles associated with current mode regulators. The operating frequency is adjustable from 50kHz to 500kHz to allow optimization of size and efficiency. To reduce EMI, a frequency synchronization pin allows multiple IC’s from the LM(2)557x family to self-synchronize or to synchronize to an external clock. The LM5576 guarantees robustness with cycle-by-cycle current limit, short-circuit protection, thermal shut-down, and remote shut-down. The device is available in a power enhanced TSSOP-20 package featuring an exposed die attach pad for thermal dissipation. The LM5576 is supported by the full suite of WEBENCH® On-Line design tools.

Features

■ Integrated 75V, 170mΩ N-channel MOSFET

■ Ultra-wide input voltage range from 6V to 75V

■ Adjustable output voltage as low as 1.225V

■ 1.5% feedback reference accuracy

■ Operating frequency adjustable between 50kHz and 500kHz with single resistor

■ Master or slave frequency synchronization

■ Adjustable soft-start

■ Emulated current mode control architecture

■ Wide bandwidth error amplifier

■ Built-in protection

Package

■ TSSOP-20EP (Exposed Pad)

Simplified Application Schematic