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Contents

README

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1SMA5921BT3G

onsemi · Zener Diodes · SMA

1SMA5921BT3G from onsemi, in a SMA. 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 CATHODE passive Cathode terminal of the Zener regulator, identified by the molded polarity notch or cathode band; the datasheet specifies the cathode as pin 1 (Style 1).
2 ANODE passive Anode terminal of the Zener regulator; the datasheet specifies a maximum forward voltage of VF = 1.5 V at IF = 200 mA for all types.

Key specifications

Parameter Value
Manufacturer onsemi
Package SMA
Category Diodes
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
Reverse Zener Voltage VZ 6.46 6.8 7.14 V @ IZT = 55.1 mA (TA = 25°C) 2
Zener voltage tolerance (type number 5% designation) -5 5 % Type number 1SMA5921BT3G indicates 5% tolerance (Note 3) 2
Maximum Zener Impedance ZZT 2.5 Ω @ IZT = 55.1 mA 2
Maximum Zener Impedance ZZK 200 Ω @ IZK = 1.0 mA 2
Reverse Leakage Current IR 2.5 µA @ VR = 5.2 V 2
Forward Voltage VF 1.5 V @ IF = 200 mA 2
Maximum DC Zener Current IZM 221 mA 2
DC Power Dissipation PD 1.5 W @ TL = 75°C, measured zero lead length (Note 1) 1
DC Power Dissipation PD 0.5 W @ TA = 25°C (Note 2) 1
Operating and Storage Temperature Range TJ, Tstg -65 150 °C 1
Thermal Resistance, Junction-to-Lead RθJL 50 °C/W Note 1 (1 in² copper pad, FR-4) 1
Thermal Resistance, Junction-to-Ambient RθJA 250 °C/W Note 2 (FR-4, ON Semiconductor minimum recommended footprint) 1

CAD (KiCad official)

  • Symbol: 1SMA5921BT3G
  • Footprint: Diode_SMD:D_SMA
  • 3D model: SMA (KiCad packages3D, STEP)
  • 3D model files: 1sma5921bt3g-etched.step / 1sma5921bt3g-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); 1sma5921bt3g.step / 1sma5921bt3g.glb are the bare package body.

Provenance

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

  • Datasheet: onsemi datasheet (5 pp, sha256 1ca169f64a35c9ee, retrieved 2026-10-21, tier: manufacturer)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-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