RY3408 from RYCHIP, in a SOT-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	EN	input	Chip enable input. Drive above 1.5V (typ. rising threshold 1.15V, hysteresis 140mV) to turn the regulator on; drive below 0.3V to shut it down (shutdown current <1µA). Must not be left floating. Absolute max 6.0V.
2	GND	power_in	Device ground return. Connect to a large copper area to improve thermal performance and provide a low-impedance return for the input capacitor and internal low-side NMOS.
3	SW	output	Switch-node output; drains of the internal P-channel and N-channel power MOSFETs. Connect to the external inductor. Peak SW sink/source current is rated to 3A; absolute max voltage -0.3V to (VIN+0.3V).
4	IN	power_in	Power supply input, 2.5V to 5.5V operating (absolute max 6.0V). Must be closely decoupled to GND with a 10µF or greater ceramic capacitor placed near the pin.
5	FB	input	Output-voltage feedback input. Connect to the external resistor divider tap; the regulator servos FB to the internal 0.600V reference (VOUT = 0.6V x (R1+R2)/R2). Absolute max 6.0V.

Key specifications

Parameter	Value
Manufacturer	RYCHIP
Package	SOT-23-5
Category	PMIC
Pins	5

Ordering variants

Same part, different packaging or reel option.

RY3408

CAD (KiCad official)

Symbol: RY3408
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`ry3408.step`	85 KB	You want the bare part, or you mark your own boards.
`ry3408-etched.step`	1.6 MB	You want the part with `RY3408` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 373 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: RYCHIP datasheet (9 pp, sha256 dff34b6a65435b27, retrieved 2026-08-17, tier: lcsc)
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