OB3636AMP from OB On Bright Elec, 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	FB	input	Voltage feedback from auxiliary winding. Connected to a resistor divider from the auxiliary winding to reflect the output voltage; also used for quasi-resonant valley detection (new PWM cycle initiated when FB falls below ~0V). Absolute max -0.3 to 7V.
2	GND	power_in	Power ground. Return for VDD supply, CS sense resistor, CMP compensation capacitor, and FB divider.
3	VDD	power_in	Power supply pin. UVLO(OFF) turn-on threshold ~22.5V (VDD rising), UVLO(ON) turn-off threshold ~8.1V (VDD falling). VDD OVP at ~32V typical. Absolute max 40V. Start-up current ~3uA typ; operating current ~850uA typ at VDD=20V.
4	GATE	output	Gate driver output for external power MOSFET. Internally clamped to 12V typ to protect MOSFET gate. Rise time 80ns, fall time 30ns with CL=1nF. Absolute max -0.3 to 40V.
5	CS	input	Current sense input. Connect an external sense resistor between the MOSFET source and GND to this pin for cycle-by-cycle current limiting. Internal 300ns leading edge blanking suppresses turn-on spikes; OCP threshold ~0.7V typ (at Ton=0us). Absolute max -0.3 to 7V.
6	CMP	output	Loop compensation pin, internally connected to the error amplifier (transconductance ~40uS) output. A capacitor between CMP and GND sets loop bandwidth (<20Hz to suppress AC line ripple). Absolute max -0.3 to 7V.

Key specifications

Parameter	Value
Manufacturer	OB On Bright Elec
Package	SOT-23-6
Category	LED-drv
Pins	6

Ordering variants

Same part, different packaging or reel option.

OB3636AMP

CAD (KiCad official)

Symbol: OB3636AMP
Footprint: Package_TO_SOT_SMD:SOT-23-6
3D model: SOT-23-6 (KiCad packages3D, STEP)

Provenance

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

Datasheet: OB On Bright Elec datasheet (10 pp, sha256 e5a0e38b2dd607ab, 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