# SM540A

**LRC** · Schottky Barrier Diodes (SBD) · DO-214AC

SM540A from LRC, in a DO-214AC. 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 terminal, marked by the color band on the package; rated for 40V maximum repetitive peak reverse voltage and 40V DC blocking voltage (SM540A). |
| 2 | A | passive | Anode terminal, opposite the color-banded cathode end; SM540A passes 5.0A maximum average forward rectified current at TA = 80°C. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | LRC |
| Package | DO-214AC |
| 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 |
|---|---|---|---|---|---|---|---|
| Maximum repetitive peak reverse voltage | VRRM |  |  | 40 | V |  | 1 |
| Maximum RMS voltage | VRSM |  |  | 28 | V |  | 1 |
| Maximum DC blocking voltage | VDC |  |  | 40 | V |  | 1 |
| Maximum average forward rectified current | IF(AV) |  |  | 5 | A | TA = 80°C | 1 |
| Peak forward surge current | IFSM |  |  | 100 | A | 8.3ms single half sine-wave superimposed on rated load (JEDEC Method) | 1 |
| Operating junction and storage temperature range | TJ, TSTG | -40 |  | 150 | °C |  | 1 |
| Typical thermal resistance | RθJA |  | 50 |  | °C/W | Note 1: 8.0mm2 (.013mm thick) land areas | 1 |

## CAD (KiCad official)

- Symbol: `SM540A`
- Footprint: `Diode_SMD:D_SMA`
- 3D model: DO-214AC (KiCad packages3D, STEP)
- 3D model files: `sm540a-etched.step` / `sm540a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sm540a.step` / `sm540a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [LRC datasheet](docs/sm540a-datasheet.pdf) (9 pp, sha256 `3cab7e4290cabad4`, retrieved 2026-10-22, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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](docs/sm540a-datasheet.pdf)