1 Features

1? Versatile Synchronous Buck DC/DC Converter

– Operating Input Voltage Range of 9 V to 75 V

– Integrated 80-V, 0.7-A N-Channel Buck Switch

– Internal High-Voltage VCC Regulator

– Adjustable Output Voltage

– High Efficiency Operation

? Adaptive Constant On-Time Control Architecture

– Ultra-Fast Transient Response

– No Control Loop Compensation Required

? Nearly Constant Switching Frequency

– PWM On-Time Varies Inversely with Input

Voltage

? Precision 2.5-V Reference

? Low Input Quiescent Current

? Inherent Protection Features for Robust Design

– Intelligent Current Limit Protection

– VCC and Gate Drive UVLO Protection

– Thermal Shutdown Protection With Hysteresis

– External Shutdown Control

? 8-Pin VSSOP and WSON Packages

? Create a Custom Regulator Design Using

WEBENCH? Power Designer

2 Applications

? Non-Isolated DC/DC Buck Regulator

? Secondary High-Voltage Post Regulator

? 48-V Automotive Systems

3 Description

The LM5007 0.5-A step-down switching converter

features all of the functions needed to implement a

low-cost and efficient buck regulator. This highvoltage

converter has an integrated 80-V, 0.7-A Nchannel

buck switch and operates over an input

voltage range of 9 V to 75 V. The device is easy to

implement and is provided in 8-pin VSSOP and

thermally enhanced 8-pin WSON packages.

The converter uses a hysteretic control scheme with

a PWM on-time inversely proportional to VIN. This

feature allows the operating frequency to remain

relatively constant with load and input voltage

variations. The hysteretic control requires no loop

compensation and provides fast transient response.

An intelligent current limit is implemented with forced

off-time that is inversely proportional to VOUT. This

current limiting scheme ensures short-circuit

protection while providing reduced load current

foldback. Other protection features include thermal

shutdown with automatic recovery, VCC and gate

drive undervoltage lockout, and maximum duty cycle

limiter.