1 Features

• Qualified for extended temperature applications

– Device temperature:

–55°C to +125°C ambient operating

temperature range

• 3-V to 65-V input range

• Reverse input protection down to –65 V

• Drives external back-to-back N-channel MOSFETs

in common drain and common source

configurations

• Ideal diode operation with 10.5-mV A to C forward

voltage drop regulation (LM74800)

• Low reverse detection threshold (–4.5 mV) with

fast response (0.5 μs)

• 20-mA peak gate (DGATE) turnon current

• 2.6-A peak DGATE turnoff current

• Adjustable overvoltage protection

• Low 2.87-μA shutdown current (EN/UVLO = Low)

• Available in space saving 12-pin WSON package

2 Applications

• Avionics Input reverse polarity protection

– Sensors

– Imaging

– Radar

• Active ORing for redundant power

3 Description

The LM7480 ideal diode controller drives and controls

external back to back N-channel MOSFETs to

emulate an ideal diode rectifier with power path

ON/OFF control and overvoltage protection. The wide

input supply of 3 V to 65 V allows protection and

control of 12-V and 24-V input powered systems.

The device can withstand and protect the loads

from negative supply voltages down to –65 V. An

integrated ideal diode controller (DGATE) drives the

first MOSFET to replace a Schottky diode for reverse

input protection and output voltage holdup. With a

second MOSFET in the power path the device allows

load disconnect (ON/OFF control) and overvoltage

protection using HGATE control. The device features

an adjustable overvoltage cut-off protection feature.

LM7480 has two variants, LM74800 and LM74801.

LM74800 employs reverse current blocking using

linear regulation and comparator scheme versus

LM74801, which supports a comparator based

scheme. With common-drain configuration of the

power MOSFETs, the mid-point can be utilized for

OR-ing designs using another ideal diode. The

LM7480 has a maximum voltage rating of 65 V. The

loads can be protected from extended overvoltage

transients like 200-V unsuppressed load dumps in

24-V battery systems by configuring the device with

external MOSFETs in common source topology.