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Contents

README

markdown

SZ1SMA28CAT3G

Littelfuse · TVS · SMA

SZ1SMA28CAT3G from Littelfuse, 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 Terminal 1 is marked as cathode in the generic part-marking diagram, but the datasheet states the cathode indicator applies to uni-directional devices only, so this bi-directional part has no defined polarity.
2 Anode passive Terminal 2 is marked as anode in the generic part-marking diagram, and the device clamps transients with a 400 W peak power rating at 1 ms, per the datasheet.

Key specifications

Parameter Value
Manufacturer Littelfuse
Package SMA
Category TVS/Fuse/Board Level Protection
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
Breakdown Voltage VBR 31.1 32.74 34.37 V @ IT, IT = 1 mA 4
Maximum Reverse Leakage Current IR 2.5 µA @ VRWM 4
Peak Power Dissipation PPK 400 W TL = 25°C, pulse width 1 ms (Note 1) 1
DC Power Dissipation @ TL PD 1.5 W TL = 75°C, measured zero lead length (Note 2) 1
DC Power Dissipation @ TA PD 0.5 W TA = 25°C (Note 3) 1
Operating and Storage Temperature Range TJ, Tstg -65 175 °C 1
Clamping Voltage VC 45.4 V @ IPP, IPP = 8.8 A 4
Working Peak Reverse Voltage VRWM 28 V 4
Thermal Resistance from Junction-to-Lead RθJL 50 °C/W 1
Thermal Resistance from Junction-to-Ambient RθJA 120 °C/W 1

Materials and finish

As the datasheet states them (page.json metadata.appearance; the 3D model's colours follow it).

Part Material Colour / plating Datasheet says Page
contacts tin the terminal finish material is tin(Sn) (IPC/JEDEC J-STD￾609A.01) 1

CAD (KiCad official)

  • Symbol: SZ1SMA28CAT3G
  • Footprint: Diode_SMD:D_SMA
  • 3D model: SMA (KiCad packages3D, STEP)

Provenance

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

  • Datasheet: Littelfuse datasheet (7 pp, sha256 28d8bdc1607bd94e, retrieved 2026-11-02, tier: lcsc)
  • 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