LM2731XMF from Texas Instruments, in a SOT-23-5. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	SW	output	Drain of the internal DMOS FET switch, rated -0.4 V to 22 V absolute maximum and 3 V to 20 V recommended.
2	GND	power_in	Analog and power ground for the converter.
3	FB	input	Feedback point that connects to the external resistive divider, with an absolute maximum pin voltage of -0.4 V to 6 V.
4	SHDN	input	Logic-level shutdown control input that must not float or exceed VIN + 0.3 V, and should be connected to VIN if the feature is not used.
5	VIN	power_in	Analog and power input supply, recommended 2.7 V to 14 V.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOT-23-5
Category	Power Management (PMIC)
Pins	5

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter	Symbol	Min	Typ	Max	Unit	Conditions	Page
Operating Junction Temperature		-40		125	°C		3
Lead Temperature (Soldering, 5 sec.)				300	°C	Soldering, 5 sec.	3
FB Pin Voltage		-0.4		6	V		3
SW Pin Voltage		-0.4		22	V		3
Input Supply Voltage		-0.4		14.5	V		3
SHDN Pin Voltage		-0.4			V	max VIN + 0.3 V	3
Storage Temperature	Tstg	-65		150	°C		3
VIN Input Supply Voltage	VIN	2.7		14	V		4
SW Pin Voltage	Vsw	3		20	V		4
Shutdown Supply Voltage	Vshdn	0			V	max VIN; pin must not float or exceed VIN + 0.3 V	4
Junction Temperature Range	TJ	-40		125	ºC		4
VIN Input Voltage	VIN	2.7		14	V	−40°C ≤ TJ ≤ 125°C	5
Minimum Output Voltage Under Load	VOUT (MIN)		7		V	RL = 43 Ω, VIN = 2.7 V, X option, TJ = 25°C	5
Minimum Output Voltage Under Load	VOUT (MIN)	5.4			V	RL = 43 Ω, VIN = 2.7 V, X option, −40°C ≤ TJ ≤ 125°C	5
Minimum Output Voltage Under Load	VOUT (MIN)		10		V	RL = 43 Ω, VIN = 3.3 V, X option, TJ = 25°C	5
Minimum Output Voltage Under Load	VOUT (MIN)	8			V	RL = 43 Ω, VIN = 3.3 V, X option, −40°C ≤ TJ ≤ 125°C	5
Minimum Output Voltage Under Load	VOUT (MIN)		16		V	RL = 43 Ω, VIN = 5 V, X option	5
Minimum Output Voltage Under Load	VOUT (MIN)		5		V	RL = 15 Ω, VIN = 2.7 V, X option, TJ = 25°C	5
Minimum Output Voltage Under Load	VOUT (MIN)	3.75			V	RL = 15 Ω, VIN = 2.7 V, X option, −40°C ≤ TJ ≤ 125°C	5
Minimum Output Voltage Under Load	VOUT (MIN)		6.5		V	RL = 15 Ω, VIN = 3.3 V, X option, TJ = 25°C	5
Minimum Output Voltage Under Load	VOUT (MIN)	5			V	RL = 15 Ω, VIN = 3.3 V, X option, −40°C ≤ TJ ≤ 125°C	5
Switch Current Limit	ISW	1.8	2		A	TJ = 25°C	5
Switch Current Limit	ISW	1.4			A	−40°C ≤ TJ ≤ 125°C	5
Switch ON-Resistance	RDS(ON)		260	400	mΩ	TJ = 25°C, ISW = 100 mA, Vin = 5 V	5
Switch ON-Resistance	RDS(ON)			500	mΩ	ISW = 100 mA, Vin = 5 V, −40°C ≤ TJ ≤ 125°C	5
Switch ON-Resistance	RDS(ON)		300	450	mΩ	TJ = 25°C, ISW = 100 mA, Vin = 3.3 V	5
Switch ON-Resistance	RDS(ON)			550	mΩ	ISW = 100 mA, Vin = 3.3 V, −40°C ≤ TJ ≤ 125°C	5
Shutdown Threshold, Device ON	SHDNTH	1.5			V	Device ON, −40°C ≤ TJ ≤ 125°C	5
Shutdown Threshold, Device OFF	SHDNTH			0.5	V	Device OFF, −40°C ≤ TJ ≤ 125°C	5
Shutdown Pin Bias Current	ISHDN		0		µA	VSHDN = 0, TJ = 25°C	5
Shutdown Pin Bias Current	ISHDN			2	µA	VSHDN = 5 V, −40°C ≤ TJ ≤ 125°C	5
Feedback Pin Reference Voltage	VFB		1.23		V	VIN = 3 V, TJ = 25°C	5
Feedback Pin Reference Voltage	VFB	1.205		1.255	V	VIN = 3 V, −40°C ≤ TJ ≤ 125°C	5
Feedback Pin Bias Current	IFB		60		nA	VFB = 1.23 V, TJ = 25°C	5
Feedback Pin Bias Current	IFB			500	nA	VFB = 1.23 V, −40°C ≤ TJ ≤ 125°C	5
Quiescent Current, X option, switching	IQ		2		mA	VSHDN = 5 V, Switching, TJ = 25°C	6
Quiescent Current, X option, switching	IQ			3	mA	VSHDN = 5 V, Switching, −40°C ≤ TJ ≤ 125°C	6
Quiescent Current, not switching	IQ		400		µA	VSHDN = 5 V, Not Switching, TJ = 25°C	6
Quiescent Current, not switching	IQ			500	µA	VSHDN = 5 V, Not Switching, −40°C ≤ TJ ≤ 125°C	6
Quiescent Current, shutdown	IQ		0.024	1	µA	VSHDN = 0	6
FB Voltage Line Regulation	ΔVFB/ΔVIN		0.02		%/V	2.7 V ≤ VIN ≤ 14 V	6
Switching Frequency, X option	FSW		1.6		MHz	TJ = 25°C	6
Switching Frequency, X option	FSW	1		1.85	MHz	−40°C ≤ TJ ≤ 125°C	6
Maximum Duty Cycle, X option	DMAX		86		%	TJ = 25°C	6
Maximum Duty Cycle, X option	DMAX	78			%	−40°C ≤ TJ ≤ 125°C	6
Switch Leakage	IL			1	µA	Not Switching, VSW = 5 V	6
Junction-to-ambient thermal resistance	RθJA		209.9		°C/W	DBV (SOT-23), 5 pins	4
Junction-to-case (top) thermal resistance	RθJC(top)		122		°C/W	DBV (SOT-23), 5 pins	4
Junction-to-board thermal resistance	RθJB		38.4		°C/W	DBV (SOT-23), 5 pins	4
Junction-to-top characterization parameter	ψJT		12.8		°C/W	DBV (SOT-23), 5 pins	4
Junction-to-board characterization parameter	ψJB		37.5		°C/W	DBV (SOT-23), 5 pins	4

CAD (KiCad official)

Symbol: LM2731XMF
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)
3D model files: lm2731xmf-etched.step / lm2731xmf-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); lm2731xmf.step / lm2731xmf.glb are the bare package body.

Provenance

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

Datasheet: Texas Instruments datasheet (30 pp, sha256 ff9a7a31b10ac731, retrieved 2026-11-05, tier: manufacturer)
Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF

LM2731XMF

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3D Model

Symbol & Footprint

Schematic Symbol

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Datasheet

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