HG811TM4 from HGSEMI, in a SOT-143-4. 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	GND	power_in	Ground / negative supply return.
2	VRESET	output	Active-low reset output. Pulled low when VCC drops below the threshold Vth (3.08 V typ for HG811TM4) or when MR is asserted low; returns high after the Trp reset delay (500 ms typical). VOL ≤ 0.5 V at ISINK = 3.2 mA; VOH ≥ 0.8·VCC at ISOURCE = 500 µA.
3	MR	input	Manual reset / enable input, active low. Driving MR low forces VRESET low; releasing MR high starts the Trp reset delay. VIH ≥ 0.7·VCC, VIL ≤ 0.2·VCC. Minimum pulse width tMR = 10 µs.
4	VCC	power_in	Positive supply and monitored voltage input. Operating range 1.0 V to 6.0 V (absolute max 6.5 V). Quiescent current ICCH ≈ 1 µA typ, 5 µA max at VCC = 6 V with MR high.

Key specifications

Parameter	Value
Manufacturer	HGSEMI
Package	SOT-143-4
Category	PMIC
Pins	4

Ordering variants

Same part, different packaging or reel option.

HG811TM4/TR

CAD (KiCad official)

Symbol: HG811TM4
Footprint: Package_TO_SOT_SMD:SOT-143
3D model: SOT-143-4 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`hg811tm4.step`	75 KB	You want the bare part, or you mark your own boards.
`hg811tm4-etched.step`	1.3 MB	You want the part with `HG811TM4` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 343 faces against 87 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: HGSEMI datasheet (7 pp, sha256 a75fd3d5b03be350, 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