# ams AS5040 magnetic rotary encoder IC (SSOP16) — package footprint and magnet alignment

> What are the AS5040 SSOP16 package dimensions and where does the magnet go?

- Category: Electronic components › Modules, sensors & displays
- Kind: Modern device
- Basis: ams AS5040 datasheet package drawing (SSOP16 table, rev 2.10) and magnet specification (v2-12), cross-checked with the AS5140H SSOP16 table.
- Page: https://xemstudio.com/objects/ams-as5040-ssop16/ · JSON: https://xemstudio.com/api/geometry?object=ams-as5040-ssop16 · Plain text: https://xemstudio.com/objects/ams-as5040-ssop16/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 7.8 | 6.2 | 1.73 |

**Exact dimensions.** Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part.

## Notes

- Exact nominal dimensions. Body 6.20 (D, along the pin rows) × 5.30 (E1) mm; lead tip span E = 7.80 mm; datum is the package centre, seating plane on z=0.
- 16 gull-wing leads, 8 per side, 0.65 mm pitch, lead width b 0.315 mm, foot length L 0.75 mm typ.
- Modelled height 1.73 mm (body thickness A2); the datasheet gives 1.86 mm maximum seated height (A) with a 0.13 mm standoff (A1).
- Magnet axis on the package centre; the Hall array is a Ø2.2 mm circle (radius 1.1) around the die centre, and the die may sit up to ±0.235 mm off the package centre. Keep the magnet axis within 0.25 mm of the package centre.
- Recommended magnet: diametrically magnetised cylinder Ø6 × 2.5 mm. SMD part, no mounting holes. Not modelled: lead bends, mould draft, pin-1 mark.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| SSOP16 footprint | 16 leads, 0.65 pitch, 7.80 lead span, 6.20 × 5.30 body | SSOP16 (5.3 mm body) PCB land pattern | designed | all |
| magnet axis | on package centre, ±0.25 radial; Hall circle radius 1.1 | Ø6 × 2.5 diametric magnet on the shaft end | designed | all |

## Sizes

| dimension | symbol | mm |
|---|---|---|
| body length | D | 6.2 |
| body width | E1 | 5.3 |
| lead span | E | 7.8 |
| pitch | e | 0.65 |
| lead width | b | 0.315 |
| max height | A | 1.86 |
| standoff | A1 | 0.13 |
| body thickness | A2 | 1.73 |

## Where the files are

- ams (datasheet, via elecfans): [AS5040 datasheet rev 2.10 — package drawing](https://pdf.elecfans.com/AMSCO/AS5040.html) — web — Publisher's page; dimensions are facts
- ams (datasheet, via chipsmall): [AS5040 datasheet v2-12 — magnetic input specification](https://datasheet.chipsmall.com/AS5040-ASSM/107764.pdf) — web — Publisher's page; dimensions are facts
- ams (datasheet, via dtsheet): [AS5140H datasheet v1-08 — same SSOP16 table](https://dtsheet.com/doc/1463506/pdf) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/ams-as5040-ssop16/index.json

- ams-as5040-ssop16: [STEP](https://xemstudio.com/files/hardware/ams-as5040-ssop16/ams-as5040-ssop16.step) · [STL](https://xemstudio.com/files/hardware/ams-as5040-ssop16/ams-as5040-ssop16.stl) — ams AS5040 magnetic rotary encoder IC (SSOP16) — package footprint and magnet alignment

## Questions

**What package is the AS5040?**

SSOP16 with a 5.3 mm body: 6.20 × 5.30 mm body, 7.80 mm across the leads, 0.65 mm pitch, 1.86 mm max height.

**What magnet does the AS5040 use?**

A diametrically magnetised Ø6 × 2.5 mm cylinder on the package centre axis, within 0.25 mm.

**How far off-centre can the die be?**

Up to ±0.235 mm in X and Y from the package centre; the Hall sensors sit on a 1.1 mm radius around the die centre.

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