Automotive, low IQ ideal diode controller with active rectification and load dump protection

The LM74720-Q1 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 automotive battery powered ECUs. The

device can withstand and protect the loads from negative supply

voltages down to –65 V. An integrated ideal diode controller (GATE)

drives the first MOSFET to replace a Schottky diode for reverse

input protection and output voltage holdup. A strong boost regulator

with fast turn ON and OFF comparators ensures robust and efficient

MOSFET switching performance during automotive testing such as

ISO16750 or LV124 where an ECU is subjected to input short

interruptions and AC superimpose input signals up to 100-kHz

frequency. Low Quiescent Current 35 µA (maximum) in operation

enables always ON system designs. With a second MOSFET in the power

path, the device allows load disconnect control using EN pin.

Quiescent current reduces to 3.3 µA (maximum) with EN low. The

device features an adjustable overvoltage cut-off protection feature

for load dump protection.