# Adafruit ADS1115 16-bit ADC breakout (1085, STEMMA QT): 25.4 × 17.78 mm board and mounting holes

> What are the Adafruit ADS1115 breakout dimensions and mounting-hole positions?

- Category: Electronic components › Modules, sensors & displays
- Kind: Modern device
- Basis: Adafruit's Eagle board file for the ADS1115 STEMMA QT breakout and the JST SH connector datasheet.
- Page: https://xemstudio.com/objects/adafruit-ads1115-1085/ · JSON: https://xemstudio.com/api/geometry?object=adafruit-ads1115-1085 · Plain text: https://xemstudio.com/objects/adafruit-ads1115-1085/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 |
|---|---|---|
| 25.4 | 17.78 | 4.55 |

**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

- Datum: board centred on X and Y, bottom on z=0, components up.
- Board 25.40 × 17.78 × 1.6 mm with R2.54 corners.
- Four Ø2.5 holes at (±10.16, ±6.35): a 20.32 × 12.70 mm pattern.
- Two side-entry JST SH 4-pin STEMMA QT connectors, each 4.25 × 6.10 × 2.95, centred at (±10.03, 0), openings facing outward; overall height 4.55.
- Not modelled: the two 1×6 headers along the ±Y edges (ship loose) and the ADC chip. The pre-2021 board (27.94 × 17.15, two holes) is a different part.
- Exact nominal mm.

## 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 |
|---|---|---|---|---|
| Mounting holes | 4 × Ø2.5 on 20.32 × 12.70 | M2 screws or standoffs | designed | all |
| STEMMA QT connectors | JST SH 4-pin, 1.0 pitch | STEMMA QT / Qwiic cable | socket | all |

## Sizes

| hole | x (mm) | y (mm) | diameter (mm) |
|---|---|---|---|
| 1 | -10.16 | -6.35 | 2.5 |
| 2 | 10.16 | -6.35 | 2.5 |
| 3 | -10.16 | 6.35 | 2.5 |
| 4 | 10.16 | 6.35 | 2.5 |

## Where the files are

- Adafruit: [ADS1115 16-Bit ADC – 4 Channel with Programmable Gain Amplifier](https://www.adafruit.com/product/1085) — web — Publisher's page; dimensions are facts
- Adafruit (GitHub): [ADS1X15 Breakout Board PCB files](https://github.com/adafruit/ADS1X15-Breakout-Board-PCBs) — web — Publisher's page; dimensions are facts
- Adafruit Learn: [Adafruit 4-Channel ADC Breakouts](https://learn.adafruit.com/adafruit-4-channel-adc-breakouts) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/adafruit-ads1115-1085/index.json

- adafruit-ads1115-1085: [STEP](https://xemstudio.com/files/hardware/adafruit-ads1115-1085/adafruit-ads1115-1085.step) · [STL](https://xemstudio.com/files/hardware/adafruit-ads1115-1085/adafruit-ads1115-1085.stl) — Adafruit ADS1115 16-bit ADC breakout (1085, STEMMA QT): 25.4 × 17.78 mm board and mounting holes

## Questions

**How big is the Adafruit ADS1115 breakout?**

25.40 × 17.78 mm (STEMMA QT version), 4.55 mm tall over the connectors.

**Where are the mounting holes?**

Four Ø2.5 holes on a 20.32 × 12.70 mm rectangle centred on the board.

## Fits with

- [Adafruit STEMMA QT sensor breakouts (BME280, BNO055/085, VL53, SCD-40, AHT20, SHT40, IMUs, light, magnet, RTC…)](https://xemstudio.com/objects/adafruit-stemma-qt-breakouts/)
- [JST SH connector (1.0 mm pitch): wire, ratings, circuits](https://xemstudio.com/objects/jst-sh-connector/)
- [2.54 mm pin headers, 1×2 to 2×20, vertical and right-angle](https://xemstudio.com/objects/pin-headers-2.54mm/)
- [Threaded standoffs, M2.5 and M3 (hex and round)](https://xemstudio.com/objects/threaded-standoffs-metric/)
- [Adafruit BME280 breakout (original)](https://xemstudio.com/objects/adafruit-bme280-breakout-original/)