# SMBJ8.5A

**FTR** · TVS · DO-214AA(SMB)

SMBJ8.5A from FTR, in a DO-214AA(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 banded/marked end per the datasheet; pad 1 of the KiCad diode footprint. |
| 2 | A | passive | Anode. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | FTR |
| Package | DO-214AA(SMB) |
| Category | Circuit 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 |
|---|---|---|---|---|---|---|---|
| Reverse stand-off voltage (unidirectional SMBJ8.5A) | VRWM |  |  | 8.5 | V |  | 2 |
| Breakdown voltage | VBR | 9.4 |  | 10.4 | V | IT = 1 mA | 2 |
| Maximum clamping voltage | VC |  |  | 14.4 | V | IPP = 41.7 A | 2 |
| Reverse leakage current | IR |  |  | 10 | μA | @VRWM | 2 |
| Peak pulse power dissipation | PPPM | 600 |  |  | W | 10/1000μs waveform (Note 1, Fig.1) | 1 |
| Peak pulse current | IPPM |  |  | 41.7 | A | 10/1000μs waveform (Note 1, Fig.3); value from IPP column for SMBJ8.5A | 1 |
| Steady state power dissipation | PM(AV) |  |  | 5 | W | TL=75℃ (Fig.4) | 1 |
| Peak forward surge current | IFSM |  |  | 100 | A | 8.3ms single half sine-wave, JEDEC method (Note 2) | 1 |
| Operating junction and storage temperature range | TJ,TSTG | -55 |  | 150 | ℃ |  | 1 |
| Thermal resistance junction to lead | RθJL |  | 20 |  | ℃/W | Typical | 1 |
| Thermal resistance junction to ambient | RθJA |  | 100 |  | ℃/W | Typical | 1 |
| Average ramp-up rate (TL to TP) |  |  |  | 3 | ℃/second | Pb-free assembly reflow profile | 4 |
| Preheat temperature min | TS min | 150 |  |  | ℃ | Pb-free assembly reflow profile | 4 |
| Preheat temperature max | TS max |  |  | 200 | ℃ | Pb-free assembly reflow profile | 4 |
| Preheat time | tS | 60 |  | 180 | seconds | Preheat, min to max | 4 |
| Ramp-up rate (TS max to TL) |  |  |  | 3 | ℃/second | Pb-free assembly reflow profile | 4 |
| Time maintained above liquidus temperature | tL | 60 |  | 150 | seconds | Time above TL = 217℃ | 4 |
| Liquidus temperature | TL |  | 217 |  | ℃ | Time maintained above TL | 4 |
| Peak temperature | TP |  |  | 260 | ℃ | Pb-free assembly reflow profile | 4 |
| Time within 5℃ of actual peak temperature | tP | 20 |  | 40 | seconds | Within 5℃ of actual peak temperature | 4 |
| Ramp-down rate |  |  |  | 6 | ℃/second | Pb-free assembly reflow profile | 4 |
| Time 25℃ to peak temperature |  |  |  | 8 | minutes | Pb-free assembly reflow profile | 4 |

## CAD (KiCad official)

- Symbol: `SMBJ8.5A`
- Footprint: `Diode_SMD:D_SMB`
- 3D model: DO-214AA(SMB) (KiCad packages3D, STEP)
- 3D model files: `smbj8-5a-etched.step` / `smbj8-5a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `smbj8-5a.step` / `smbj8-5a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [FTR datasheet](docs/smbj8-5a-datasheet.pdf) (6 pp, sha256 `0d5134e86f94d39e`, retrieved 2026-10-21, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins`, primary `cathode-band convention` (convention), consensus `off` (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](docs/smbj8-5a-datasheet.pdf)