The LM74700-EP is an 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 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 power
fail and input micro-short conditions.
The LM74700-EP controller provides a charge pump
gate drive for an external N-channel MOSFET. The high voltage rating of LM74700-EP
helps to simplify the system designs for automotive ISO7637 protection. With the
enable pin low, the controller is off and draws approximately 1 µA of current. The
LM74700-EP is fully specified over the temperature range of TA = –55°C to
+125°C.
Device Information(1)PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|
LM74700-EP | SOT-23 (8) | 2.90 mm × 1.60
mm |
(1) For all available packages, see the orderable addendum at the end of the data sheet.
Typical Application Schematic
Reverse Current Blocking During Input Short