NS4150B from Shenzhen Nsiway Tech, in a MSOP-8. 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	CTRL	input	Operating mode control. Logic high (VIH ≥ 1.2V, up to VDD) enables the amplifier; logic low (VIL ≤ 0.2V) puts the device into shutdown. Typical shutdown leakage 0.1µA at VDD=3.6V.
2	Bypass	passive	Internal common-mode voltage bypass. Connect a 1µF ceramic capacitor from this pin to GND to filter the internal mid-supply reference.
3	INP	input	Positive audio input. AC-coupled through a series capacitor and input resistor Rin; combined with the internal 240kΩ feedback resistor to set differential gain AVD = 240kΩ / Rin.
4	INN	input	Negative audio input. AC-coupled through a series capacitor and input resistor Rin; used differentially with INP, or grounded through Cin/Rin for single-ended input.
5	VON	output	Negative Class-D BTL audio output. Drives one side of the speaker load (4Ω or 8Ω); filterless PWM output, optional ferrite bead + 1nF cap for EMI suppression on long speaker leads.
6	VCC	power_in	Supply input and power stage supply. Recommended operating range 2.2V-5.0V (absolute max 5.25V). Decouple with a 1µF ceramic close to the pin, optionally add 10µF for low-frequency filtering.
7	GND	power_in	Device ground. Return path for supply, bypass capacitor, and speaker EMI filter capacitors.
8	VOP	output	Positive Class-D BTL audio output. Drives the other side of the speaker load; filterless PWM output, optional ferrite bead + 1nF cap for EMI suppression.

Key specifications

Parameter	Value
Manufacturer	Shenzhen Nsiway Tech
Package	MSOP-8
Category	Op-amp/Cmp
Pins	8

CAD (KiCad official)

Symbol: NS4150B
Footprint: Package_SO:MSOP-8_3x3mm_P0.65mm
3D model: MSOP-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`ns4150b.step`	123 KB	You want the bare part, or you mark your own boards.
`ns4150b-etched.step`	1.7 MB	You want the part with `NS4150B` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 427 faces against 147 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: Shenzhen Nsiway Tech datasheet (9 pp, sha256 8f26ce641fd0ead9, 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