component
SZ1SMB43AT3G
Public Made by Adomby adom
Littelfuse TVS, SMB. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
3D Model
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Symbol & Footprint
Schematic Symbol
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PCB Footprint
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Datasheet
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Contents
README
markdownSZ1SMB43AT3G
Littelfuse · TVS · SMB
SZ1SMB43AT3G from Littelfuse, 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 | Cathode | passive | Cathode of the unidirectional TVS diode, marked by the color band; connect to the positive/protected line, with VRWM of 43 V and VBR of 47.8 V to 52.8 V at 1.0 mA. |
| 2 | Anode | passive | Anode of the unidirectional TVS diode, normally connected to ground; clamps at VC 69.4 V at IPP 8.6 A. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Littelfuse |
| Package | SMB |
| 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 | 47.8 | 50.3 | 52.8 | V | @ IT = 1.0 mA, TA=25°C | 3 |
| Working Peak Reverse Voltage | VRWM | 43 | V | 3 | |||
| Maximum Reverse Leakage Current | IR | 5 | µA | @ VRWM | 3 | ||
| Clamping Voltage | VC | 69.4 | V | @ IPP = 8.6 A | 3 | ||
| Maximum Reverse Peak Pulse Current | IPP | 8.6 | A | 3 | |||
| Forward Voltage | VF | 3.5 | V | IF = 30 A, TA=25°C, uni-directional | 2 | ||
| Peak Power Dissipation | PPK | 600 | W | TL = 25°C, Pulse Width = 1 ms, 10/1000 µs non-repetitive | 1 | ||
| DC Power Dissipation (lead) | PD | 3 | W | TL = 75°C, zero lead length, 1" square copper pad FR-4 | 1 | ||
| DC Power Dissipation (ambient) | PD | 0.55 | W | TA = 25°C, FR-4 board, minimum recommended footprint | 1 | ||
| Forward Surge Current | IFSM | 100 | A | TA = 25°C, 1/2 sine wave PW = 8.3 ms, uni-directional only | 1 | ||
| Operating and Storage Temperature Range | TJ, Tstg | -65 | 175 | °C | 1 | ||
| Thermal Resistance Junction-to-Lead | RƟJL | 25 | °C/W | 1 | |||
| Thermal Resistance Junction-to-Ambient | RƟJA | 100 | °C/W | 1 | |||
| Capacitance | C | 400 | pF | Bias Voltage = 0 V, F = 1 MHz, TJ = 25°C | 3 |
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-STD609A.01) | 1 |
CAD (KiCad official)
- Symbol:
SZ1SMB43AT3G - Footprint:
Diode_SMD:D_SMB - 3D model: SMB (KiCad packages3D, STEP)
- 3D model files:
sz1smb43at3g-etched.step/sz1smb43at3g-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);sz1smb43at3g.step/sz1smb43at3g.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Littelfuse datasheet (7 pp, sha256
9b427104bf8c86ce, retrieved 2026-10-27, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-sonnet-5-5(text), consensusclaude-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).