Adafruit TCA9548A 1-to-8 I2C multiplexer (#2717): 17.78 × 30.48 mm board and 2 mounting holes — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/adafruit-tca9548a-2717/  (sheet CC BY 4.0)
Basis: Adafruit's EagleCAD board file for the TCA9548A I2C multiplexer breakout, including its own dimension lines.
Catalog version: 2026-10-20

Overall (mm): length 30.48, width 17.78, height 1.6
- Board 17.78 × 30.48 with square corners, centred, board bottom at 0. Board thickness 1.6 is assumed (Adafruit's board file does not state it); everything else is from the board file.
- Two plated Ø2.5 mounting holes on the long centre line at (0, ±12.70): 25.40 apart, 2.54 in from each short edge.
- No STEMMA QT connectors on this SKU (2717); Adafruit's STEMMA QT I2C mux is a different board (PCA9548, product 5626).
- Not modelled: the two loose 1×12 0.1 in headers along the long edges, the TSSOP-24 chip and passives.
- All dimensions are exact nominal millimetres, true size, with no tolerance added.

hole  x (mm)  y (mm)  diameter (mm)
1  0  -12.70  2.5
2  0  +12.70  2.5

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Adafruit: TCA9548A I2C Multiplexer (#2717) — web — Publisher's page; dimensions are facts — https://www.adafruit.com/product/2717
- Adafruit: Adafruit-TCA9548A-I2C-Multiplexer-PCB repository — web — Publisher's page; dimensions are facts — https://github.com/adafruit/Adafruit-TCA9548A-I2C-Multiplexer-PCB
- Adafruit Learning System: Adafruit TCA9548A 1-to-8 I2C Multiplexer Breakout guide — web — Publisher's page; dimensions are facts — https://learn.adafruit.com/adafruit-tca9548a-1-to-8-i2c-multiplexer-breakout

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/adafruit-tca9548a-2717/index.json
API: https://xemstudio.com/api/geometry?object=adafruit-tca9548a-2717