LM3404HVMRX from Texas Instruments, in a SO-8-EP. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	SW	output	Switch pin. Connect this pin to the output inductor and Schottky recirculating diode. Internal high-side N-channel MOSFET drain; swings between VIN and roughly -1 V during freewheel. Absolute rating -1.5 V to 76 V (LM3404HV).
2	BOOT	power_in	MOSFET drive bootstrap pin. Connect a 10-nF ceramic capacitor from this pin to SW to develop the gate-drive rail above VIN. Absolute rating BOOT-to-SW 14 V max.
3	DIM	input	Input for PWM dimming. Connect a logic-level PWM signal to this pin to enable and disable the internal power MOSFET and reduce the average LED array light output. Absolute rating -0.3 V to 7 V.
4	GND	power_in	Ground pin. Connect this pin to system ground; also serves as the return for internal control circuits.
5	CS	input	Current sense feedback pin. Set the current through the LED array by connecting a sense resistor from this pin to ground; regulated to 200-mV (typ) threshold. Overvoltage threshold 300 mV. Absolute rating -0.3 V to 7 V.
6	RON	input	On-time control pin. A resistor connected from this pin to VIN sets the regulator's controlled on-time (hysteretic constant on-time control). Also acts as a low-voltage shutdown when pulled low (VSD-TH ~0.7 V).
7	VCC	power_out	Output of the internal 7-V linear regulator that supplies gate drive and control circuits. Bypass this pin to ground with a minimum 0.1-µF ceramic capacitor with X5R or X7R dielectric. Absolute rating -0.3 V to 14 V.
8	VIN	power_in	Input voltage pin. Nominal operating input range is 6 V to 42 V (LM3404) or 6 V to 75 V (LM3404HV). Absolute rating -0.3 V to 76 V (HV).

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SO-8-EP
Category	LED-drv
Pins	8

Ordering variants

Same part, different packaging or reel option.

LM3404HVMRX
LM3404HVMRXSD
LM3404HVMRXSDX

CAD (KiCad official)

Symbol: LM3404HVMRX
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SO-8-EP (KiCad packages3D, STEP)

Provenance

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

Datasheet: Texas Instruments datasheet (46 pp, sha256 3b94b6631f184de4, 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