1 Features

• AEC-Q100 qualified with the following results

– Device temperature grade 1:

–40°C to +125°C ambient operating

temperature range

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

• –65-V reverse voltage rating

• Charge pump for external N-Channel MOSFET

• 20-mV ANODE to CATHODE forward voltage drop

regulation

• Enable pin feature

• 1-μA shutdown current (EN=Low)

• 80-μA operating quiescent current (EN=High)

• 2.3-A peak gate turnoff current

• FETGOOD output to indicate external MOSFET

health status

• Fast response to reverse current blocking:

< 0.75 μs

• Meets automotive ISO7637 transient requirements

with a suitable TVS Diode

• 8-pin SOT-23 Package 2.90 mm × 1.60 mm

2 Applications

• Automotive ADAS systems - camera

• Automotive infotainment systems - digital cluster,

head unit

• Body electronics and lighting

• Active ORing for redundant power

3 Description

The LM74703-Q1, LM74704-Q1 is an automotive

AEC Q100 qualified ideal diode controller which

operates in conjunction with an external N-channel

MOSFET as an ideal diode rectifier for low loss

reverse polarity protection with a 20-mV forward

voltage drop. 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 automotive

battery systems. The 3.2-V input voltage support

is particularly well suited for severe cold crank

requirements in automotive systems. The device can

withstand and protect the loads from negative supply

voltages down to –65 V.

The device controls the GATE of the MOSFET to

regulate the forward voltage drop at 20 mV. The

regulation scheme enables graceful turn off of the

MOSFET during a reverse current event and ensures

zero DC reverse current flow. Fast response (<

0.75 μs) to reverse current blocking makes the

device suitable for systems with output voltage holdup

requirements during ISO7637 pulse testing as well as

power fail and input micro-short conditions. LM74703-

Q1, LM74704-Q1 has FETGOOD output to indicate

external MOSFET drain to source short or open

condition. The device features enable pin (EN). With

the enable pin low, the controller is off and draws

approximately 1 μA of current.