RT9742GGJ5 from Richtek Tech, in a TSOT-23-5. 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	VOUT	power_out	Switched power output. Delivers up to ~1A (typ. current-limit 1.4A for the G-current option) from VIN through the internal N-MOSFET high-side switch. Requires a 0.1uF ceramic COUT for stability; internal auto-discharge pulls VOUT to GND when the switch is disabled.
2	GND	power_in	Device ground reference for the bias, control logic and the source-referred protection circuitry.
3	FLG	output	Active-low, open-drain fault flag. Pulled low after an over-current or over-temperature condition persists for approximately 10ms (deglitched). Requires an external pull-up resistor (typ. to VIN or a logic rail).
4	EN	input	Chip-enable input. For the RT9742G option this pin is ACTIVE HIGH: drive high (up to 6V) to turn the power switch on, drive low to turn it off. Absolute-max range -0.3V to 7V; no internal pull, so must be driven or externally biased.
5	VIN	power_in	Power input, 2.7V to 6V recommended (7V abs-max). Source for the switched output and internal bias. Bypass with a 10uF ceramic CIN close to the pin.

Key specifications

Parameter	Value
Manufacturer	Richtek Tech
Package	TSOT-23-5
Category	PMIC
Pins	5

Ordering variants

Same part, different packaging or reel option.

RT9742GGJ5
RT9742GGJ5F
RT9742GGJ5MGJ5
RT9742GGJ5MNGJ5
RT9742GGJ5UNGJ5
RT9742GGJ5JNGV
RT9742GGJ5KNGV
RT9742GGJ5LNGV
RT9742GGJ5SNGV

CAD (KiCad official)

Symbol: RT9742GGJ5
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: TSOT-23-5 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`rt9742ggj5.step`	85 KB	You want the bare part, or you mark your own boards.
`rt9742ggj5-etched.step`	1.9 MB	You want the part with `RT9742GGJ5` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 470 faces against 102 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

Datasheet: Richtek Tech datasheet (19 pp, sha256 ed44fd2fbcb11dc2, 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