BL9342 from BL Shanghai Belling, in a SOT-23-6. 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	BST	passive	Bootstrap pin. Positive supply for the internal floating high-side MOSFET driver. Connect a bypass capacitor (typ. 100 nF) between BST and SW; capacitor is charged from an internal regulator to ~5 V.
2	GND	power_in	Ground. Route as close as possible to the output capacitor return and away from high-current switching paths.
3	FB	input	Feedback input to the internal error amplifier. An external resistor divider from VOUT to GND sets the regulated output voltage, compared against the internal 0.794 V (typ. 0.8 V) reference. Recommended R1 ≈ 124 kΩ for optimal loop response.
4	EN	input	Enable input, active high. VIH ≥ 1.6 V (typ. 2.0 V) turns the chip on; pulling below the threshold shuts it down. Hysteresis 0.6 V. Internally pulled to GND so floating EN disables the part; do not leave floating in operation.
5	VIN	power_in	Power supply input, 4.2 V to 40 V (absolute max 43 V). Supplies all internal control circuitry and the integrated high-side power MOSFET. Decouple to GND with a low-ESR capacitor (e.g. 4.7 µF/50 V) placed close to the pin to minimise switching spikes.
6	SW	output	Switch node output from the internal high-side power MOSFET (RDS(on) ≈ 500 mΩ). Connect the inductor here and place a low-VF Schottky freewheeling diode from SW to GND close to the pin. Rated up to VIN (max 40 V).

Key specifications

Parameter	Value
Manufacturer	BL Shanghai Belling
Package	SOT-23-6
Category	PMIC
Pins	6

CAD (KiCad official)

Symbol: BL9342
Footprint: Package_TO_SOT_SMD:SOT-23-6
3D model: SOT-23-6 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`bl9342.step`	97 KB	You want the bare part, or you mark your own boards.
`bl9342-etched.step`	1.5 MB	You want the part with `BL9342` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 362 faces against 117 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: BL Shanghai Belling datasheet (10 pp, sha256 f05713c35e4f834e, 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