Features of the LM74700-Q1

Features the following AEC-Q100 qualified

Device Temperature Grade 1: –40°C to +125°C ambient operating temperature range

Device HBM ESD Classification Level 2

Device CDM ESD Classification Level C4B

Provide functional safety

Documentation to aid in functional safety system design

3.2V to 65V Input Range (3.9V Startup)

-65V reverse voltage rating

Charge Pump for External N-Channel MOSFET

20mV anode-to-cathode forward voltage drop regulation

Enable Pin Characteristics

1μA Shutdown Current (EN = Low)

80µA Operating Quiescent Current (EN = High)

2.3A Peak Gate Off Current

Fast response reverse current blocking: less than 0.75μs

Complies with automotive ISO7637 transient requirements with suitable TVS diodes

2.90mm × 1.60mm in 6-pin and 8-pin SOT-23 packages

Description of LM74700-Q1

The LM74700-Q1 is an automotive AEC Q100 qualified ideal diode controller that operates in conjunction with an external N-channel MOSFET as an ideal diode rectifier for low loss reverse protection with a 20mV forward voltage drop. The wide power supply input range of 3.2V to 65V enables control of many common DC bus voltages such as 12V, 24V and 48V automotive battery systems. 3.2V input voltage support is suitable for demanding cold cranking requirements in automotive systems. The device tolerates negative supply voltages down to –65V and provides load protection.

The device regulates the forward voltage drop to 20mV by controlling the gate of the MOSFET. This current regulation scheme supports smooth shutdown during reverse current events and ensures zero DC reverse current. The device's fast (< 0.75μs) response to reverse current blocking makes it suitable for systems that require output voltage to be maintained during ISO7637 pulse testing as well as power failure and input micro-short-circuit conditions.

The LM74700-Q1 controller provides charge pump gate drivers for external N-channel MOSFETs. The high voltage rating of the LM74700-Q1 helps simplify system design for automotive ISO7637 protection. When the enable pin is low, the controller is turned off, consuming approximately 1µA of current.