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Contents

README

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SMB3Z19A

XCH(旭昌辉) · IC · SMB

SMB3Z19A from XCH(旭昌辉), in a SMB. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 K passive Cathode, the end marked by the color band; the datasheet gives a Zener voltage of 19.0 V (18.05 V min to 19.95 V max) for the SMB3Z19A.
2 A passive Anode, the end opposite the color band; the datasheet gives a maximum forward voltage of 1.2 V at 200 mA.

Key specifications

Parameter Value
Manufacturer XCH(旭昌辉)
Package SMB
Category
Pins 2

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
Zener voltage (VZ MIN / AVE / MAX) VZ 18.05 19 19.95 V @IZT 7.0 mA 3
Zener impedance (ZZT MAX) ZZT 40 Ω @IZT 7.0 mA 3
Zener impedance (ZZK MAX) ZZK 750 Ω @IZK 0.25 mA 3
Reverse leakage current (IR MAX) IR 0.5 uA @VR 14.4 V 3
Maximum DC zener current (IZM) IZM 142 mA 3
Maximum forward voltage VF 1.2 V at IF = 200 mA 1
DC power dissipation PD 3 W at TL = 75 °C (note 1) 1
Junction temperature range TJ -55 150 ℃ 1
Storage temperature range TSTG -55 150 ℃ 1

CAD (KiCad official)

  • Symbol: SMB3Z19A
  • Footprint: Diode_SMD:D_SMB
  • 3D model: SMB (KiCad packages3D, STEP)
  • 3D model files: smb3z19a-etched.step / smb3z19a-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); smb3z19a.step / smb3z19a.glb are the bare package body.

Provenance

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

  • Datasheet: XCH(旭昌辉) datasheet (3 pp, sha256 f7084c044e53fbe6, retrieved 2026-10-17, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-5-5 (text+vision), consensus claude-opus-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF