1 Features

? 3.2-V to 65-V input range (3.9-V start-up)

? –65-V input reverse voltage rating

? Integrated charge pump to drive

– External back-to-back N-Channel MOSFETs

– External high side switch MOSFET

– External reverse polarity protection MOSFET

? Gate drive variants

– LM74502: 60-μA peak gate drive source

capacity

– LM74502H: 11-mA peak gate drive source

capacity

? 2.3-A peak gate sink current capacity

? Enable pin feature

? 45-μA typical operating quiescent current (EN/

UVLO = High)

? 1-μA shutdown current (EN/UVLO = Low)

? Adjustable overvoltage and undervoltage

protection

? –40°C to +125°C ambient operating temperature

range

? Available in 8-pin SOT-23 package 2.90 mm ×

1.60 mm

2 Applications

? Factory automation and control – PLC digital

output modules

? Industrial motor drives

? Industrial transport

? Power supply reverse polarity protection

3 Description

The LM74502, LM74502H is a controller which

operates in conjunction with an external back-to-back

connected N-channel MOSFETs to realize a low

loss reverse polarity protection and load disconnect

solution. The device can also be configured to drive

high side MOSFET as a load switch with overvoltage

protection . The wide supply input range of 3.2 V

to 65 V allows control of many popular DC bus

voltages such as 12-V, 24-V and 48-V input systems.

The device can withstand and protect the loads

from negative supply voltages down to –65 V. The

LM74502, LM74502H does not have reverse current

blocking and is suitable for input reverse polarity

protection only.

The LM74502 controller provides a charge pump

gate drive for an external N-channel MOSFET. with

the enable pin low, the controller is off and draws

approximately 1 μA of current, thus offering low

system current when put into sleep mode. LM74502

and LM74502H offers programmable overvoltage and

undervoltage protection which cuts off the load from

the input source in case of these fault events. The

devices are available in a 2.9 mm × 1.6 mm 8-pin

DDF package and are specified over a –40°C to

+125°C temperature range.