FM9688AA from Shenzhen Fuman, in a SOP-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	SW	power_out	Boost converter inductor switching node; drain of the internal power MOSFET. Connect to the external boost inductor (typ. 2.2 uH) between SW and BAT. High dv/dt node - route with a short, wide trace.
2	GND	power_in	Device ground / power return for the switching stage. Tie directly to the negative terminal of the CBAT bypass capacitor and to the system ground plane without vias.
3	BAT	bidirectional	Li-ion battery positive terminal sense and charge current source. Sources up to 600 mA during constant-current charging and sinks current from the battery during boost operation. Bypass with ~10 uF ceramic capacitor to GND; use a thick trace to the cell.
4	VIN	power_in	5 V input supply from USB (recommended 4.5-5.25 V, absolute max 7 V). Powers the linear charger. UVLO rising 4.5 V, falling 3.5 V; input OVP at ~6 V. Bypass with ~1 uF ceramic (optional 1 Ω series R1).
5	DBLU	output	Discharge status LED driver (blue). Drives the discharge indicator LED to GND; blinks at 2 Hz under low-battery (VLOWQ) condition, solid/off per programmable discharge display mode.
6	DRED	output	Charge status LED driver (red). Off = not charging, blinking = charging in progress, solid = battery full. Drive an LED to GND with an appropriate series resistor.
7	TAP	input	User pushbutton input for boost enable/disable. Internally pulled high (idle ~4.9 V at VIN=5 V, ~4.15 V at VBAT=4.2 V). Short press (>40 ms) enables boost; long press (>2 s) disables it. Also supports Hall-sensor mode where a pull-low triggers boost start.
8	OUT	power_out	5 V boost output / drain of internal power P-MOS. Supplies up to 500 mA to the USB load; no-load Vout ~5.1 V, current limit ~500 mA, load-OCP threshold 4.5 V. Bypass with ~10 uF ceramic to GND.

Key specifications

Parameter	Value
Manufacturer	Shenzhen Fuman
Package	SOP-8
Category	PMIC
Pins	8

Ordering variants

Same part, different packaging or reel option.

FM9688AA
FM9688AABA

CAD (KiCad official)

Symbol: FM9688AA
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOP-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`fm9688aa.step`	122 KB	You want the bare part, or you mark your own boards.
`fm9688aa-etched.step`	2.0 MB	You want the part with `FM9688AA` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 481 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 Fuman datasheet (9 pp, sha256 7776bb744d55506f, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
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