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LM74700

Texas Instruments · Ideal diode controller · SOT-23-6

Drives an external N-channel MOSFET as an ideal diode, replacing a Schottky in the supply path with a FET that drops only millivolts, so it cuts the power lost to a series diode while still blocking reverse current. It works for reverse-polarity protection and for ORing two supplies, turning the FET on when its anode is higher and off in about a microsecond when current reverses. An EN pin gates it and an internal charge pump drives the gate. Runs from 3.2 to 65 V.

Pinout

Pin Name Type Function
1 VCAP power_out Charge-pump output. Connect a 0.1 μF ceramic capacitor from VCAP to ANODE; this reservoir supplies the ~15 V above ANODE needed to enhance the external N-channel MOSFET gate.
2 GND power_in Device ground reference. Tie to system ground; controller withstands VANODE swings down to -65 V relative to GND.
3 EN input Active-high enable input (VIL max 1.22 V, VIH min 1.06 V, hysteresis ~0.52 V). Drive high (or tie to ANODE) for always-on operation; pull low for ~1 μA shutdown. Absolute max 65 V; tolerates VANODE when VANODE ≤ 0 V.
4 CATHODE input Sense input for the ideal-diode cathode. Connect to the drain of the external N-channel MOSFET (system output rail). Recommended operating range -60 V to 60 V; ANODE-to-CATHODE regulated at 20 mV in forward conduction.
5 GATE output Gate-drive output for the external N-channel MOSFET. Sources ~11 mA peak to enhance the FET and sinks up to 2.37 A peak (2.3 A typical) during a reverse-current event for fast (<0.75 μs) turn-off. GATE-to-ANODE clamped ≤15 V.
6 ANODE power_in Input power and ideal-diode anode. Connect to the source of the external N-channel MOSFET (battery/input rail). 3.2 V to 65 V operating; POR rising ~3.9 V; requires a 22 nF (min) capacitor to GND at the pin.

Key specifications

Parameter Value
Type Ideal-diode / ORing controller
Drives External N-channel MOSFET
Input 3.2-65 V
Forward drop Set by FET RDS(on) (millivolts)
Turn-off ~0.6 us on reverse current
Enable EN pin
Package SOT-23-6

Ordering variants

Same part, different packaging or reel option.

  • LM74700QDBVR (SOT-23-6)
  • LM74700-Q1 (automotive)

CAD (KiCad official)

  • Symbol: Power_Management:LM74700 (KiCad official)
  • Footprint: Package_TO_SOT_SMD:SOT-23-6
  • 3D model: SOT-23-6 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (36 pp, sha256 e16b3a8c0023201f, retrieved 2026-08-17, tier: manufacturer)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF