# SOD diode package

Small surface-mount diode packages SOD-123, SOD-323, SOD-523 and SMF (DO-219AB), as Vishay draws them. The package is centred on the origin with the seating plane on the XY plane and its length along X. It is the moulded body, the cathode band on top at the -X end, and a lead at each end. Each lead is its own solid.

- **SOD-123 and SOD-323** have gull-wing leads: each leaves the body's end, bends down and runs out along the board to its tip. The body stands off the board.
- **SOD-523 and SMF** have flat leads: each is a strip on the board under the body's end, and the body sits on the leads.

## Source

Vishay Semiconductors, "Package Dimensions for ESD-, Zener-, Small Signal Switching-, and Schottky Diodes", document number 80128, revision 1.4, 11-Oct-2022, <https://www.vishay.com/docs/80128/package_information.pdf>. Each page is "PACKAGE DIMENSIONS in millimeters (inches)":

- SOD-123: page 25, drawing S8-V-3910.01-001, rev. 4, 24 Sep 2009.
- SOD-323: page 26, drawing S8-V-3910.02-001, rev. 6, 23 Sep 2016.
- SOD-523: page 27, drawing S8-V-3880.02-003, rev. 3, 27 May 2019.
- SMF (DO-219AB): page 31, drawing S8-V-3915.01-001, rev. 5, 09 Oct 2017.

| Package | Body length | Body width | Lead width | Height | Lead thickness | Foot | Over the leads | Standoff |
|---|---|---|---|---|---|---|---|---|
| SOD-123 | 2.55–2.85 | 1.40–1.70 | 0.45–0.65 | 1.0–1.35 | 0.10–0.15 | 0.25–0.45 | 3.55–3.85 | 0–0.1 |
| SOD-323 | 1.60–1.95 | 1.1–1.5 | 0.20–0.40 | 0.8–1.15 | 0.10–0.15 | 0.25–0.40 | 2.50–2.85 | 0–0.1 |
| SOD-523 | 1.1–1.3 | 0.7–0.9 | 0.18–0.35 | 0.55–0.75 | 0.1–0.2 | not given | 1.5–1.7 | 0–0.1 |
| SMF | 2.7–2.9 | 1.7–1.9 | 0.8–1.2 | 0.88–1.08 | 0.05–0.25 | 0.35–0.85 | 3.5–3.9 | 0–0.1 |

The foot of a gull-wing lead is measured from its tip to the inside of its bend. SMF's foot is the flat lead's whole length from its tip, as the drawing's top view gives it. The model uses the middle of each range.

**Proportions, stated plainly.** The drawings show these but don't dimension them:

- A gull-wing lead's middle leaves the body at half the body's height, and the lead runs 0.15 into the body.
- SOD-523's leads run 0.15 under the body from its ends. The drawing shows them meeting the body's ends but doesn't give their length under it.
- Leads sit in rooms cut out of the body, so no solids overlap.
- The flat-lead packages' bodies sit on the board. The drawings' 0 to 0.1 step under SOD-523's and SMF's bodies isn't modelled. A gull-wing body stands 0.05 off the board, the middle of its 0 to 0.1.
- The cathode band is 0.12 of the body's length wide, 0.1 of the length in from the -X end, and 0.03 proud of the top. The drawings mark the band but don't dimension it.
- The bodies are plain blocks. The drawn draft of the moulding's sides isn't modelled.

**Materials and mass.** The moulding is epoxy compound, mostly silica filler (density about 1.9 to 2.0), and ptfe (2.07) is the nearest in the material list. The leads are tin-plated copper alloy, shown as copper. Vishay's data sheets give each package's weight:

| Package | Model | Vishay's weight | Data sheet |
|---|---|---|---|
| SOD-123 | 11.2 mg | approx. 10.3 mg | 1N4148W, document 85748, rev. 1.8, 23-Feb-18 (LCSC's copy, datasheet.lcsc.com) |
| SOD-323 | 5.1 mg | 4 mg | 1N4148WS, document 86455, rev. 1.2, 03-Mar-2026 (LCSC's copy, datasheet.lcsc.com) |
| SOD-523 | 1.5 mg | 1.32 mg | VESD05A1-02V, document 86129, rev. 1.7, 04-Aug-2020 (vishay.com) |
| SMF | 11.8 mg | 15 mg | SMF5V0A-M to SMF58A-M, document 86330, rev. 1.1, 04-Jul-2023 (vishay.com) |

The small packages come out heavier than stated, because the plain blocks leave out the moulding's draft. SMF comes out lighter, because its lead frame inside the body isn't modelled.

## Catalogue models

The old catalogue's `D_SOD-123`, `D_SOD-323`, `D_SOD-523` and `D_SMF` entries have no models to measure. Each names its package, and each maps to Vishay's drawing of that package (SMF is DO-219AB).

The family is shared with `do214-diode` (SMA, SMB and SMC). The other surface-mount diode packages in it (SOD-123F, SOD-323F, MELF, PowerDI and the others) aren't read yet; see `COVERAGE.md`.