LM74700QDBVRQ1

The LM74700QDBVRQ1 is an automotive-qualified ideal diode controller from Texas Instruments that drives an external N-channel MOSFET to emulate an ideal diode with just 26mV forward voltage drop. AEC-Q100 Grade 1 qualified, it operates from 3V to 65V, covering the full automotive battery voltage range including load dump transients. The controller regulates the MOSFET gate to maintain 26mV across the MOSFET during forward conduction, automatically turning off the MOSFET within 0.5us when reverse current is detected. This eliminates the power dissipation and voltage drop of conventional Schottky diodes.

The LM74700 monitors the voltage across the external N-channel MOSFET between the ANODE and CATHODE pins. When forward current flows (ANODE > CATHODE), the controller drives the GATE pin 12V above ANODE to fully enhance the MOSFET, achieving near-zero voltage drop. A regulation loop maintains 26mV across the MOSFET for smooth current handling. When reverse current is detected (CATHODE > ANODE), the gate is pulled low within 0.5us, blocking reverse current. An integrated charge pump provides the gate drive voltage above the anode supply rail without external components.

• Automotive 12V/24V battery reverse polarity protection
• Redundant power supply ORing in ADAS systems
• Industrial 24V bus reverse current blocking
• Battery backup hot-swap protection
• LED driver supply polarity protection