ET-C19
Differential I²C Extender
Runs Qwiic sensors up to ~30 m over twisted pair
AED 39.00
Out of stockOverview
Runs Qwiic sensors up to ~30 m over twisted pair
The ET-C19 is built around the NXP PCA9615 — converts I²C to differential (dI²C), 1MHz Fast-mode Plus, hot-swap. It runs from 3.0–5.5V (Qwiic).
Two Qwiic / STEMMA QT connectors let you chain it with other boards without soldering, and the 2.54 mm header fits a breadboard.
Designed in Dubai by ElectroTrical — the full schematic, BOM and design notes are published below.
Good for
- Sensors across a room or greenhouse
- Long cable runs in machines
- Noisy industrial environments
Key features
What makes it different
Buffer
NXP PCA9615: converts I²C to differential (dI²C), 1MHz Fast-mode Plus, hot-swap
Distance
Up to ~30m on CAT5 twisted pairs (lower speed)
Topology
Use one board at each end; power (VIN/GND) carried on the cable
Supply
3.0–5.5V (Qwiic)
Qwiic / STEMMA QT
Two JST-SH connectors plus a 2.54 mm header — 3.3 V and 5 V hosts.
Open documentation
Schematic, BOM and layout notes published for every board.
Specifications
Technical specifications
| Buffer | NXP PCA9615: converts I²C to differential (dI²C), 1MHz Fast-mode Plus, hot-swap |
|---|---|
| Distance | Up to ~30m on CAT5 twisted pairs (lower speed) |
| Topology | Use one board at each end; power (VIN/GND) carried on the cable |
| Supply | 3.0–5.5V (Qwiic) |
| Size | 25.4 × 25.4 mm |
|---|---|
| Mounting | 4 × M2.5 holes, 2.54 mm from each corner |
| Connectors | 2 × Qwiic / STEMMA QT (JST SH 4-pin) · 4-pin 2.54 mm header |
| Main IC | PCA9615DPZ (LCSC C3824272) |
| Revision | Rev A |
| JP1 (default Closed) | Cut to turn off the LED |
|---|---|
| JP2 (default Closed) | Cut to remove the host-side I2C pull-ups |
| JP3 (default Open) | Bridge on the two end nodes: SCL pair termination |
| JP4 (default Open) | Bridge on end nodes: SDA pair termination |
Performance
Distance
Pinout
Pin map and connections
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VIN | Power | Sensor supply = host logic level |
| 2 | GND | Ground | Ground |
| 3 | SCL | I²C | I²C clock |
| 4 | SDA | I²C | I²C data |
Qwiic / STEMMA QT pins: GND, VIN, SDA, SCL (same on both connectors). I²C pull-ups (10 kΩ) are on the board; cut JP2 to remove them.
Mechanical
Dimensions and what's in the box
In the box
- 1 × ET-C19 Differential I²C Extender (assembled)
- 1 × 4-pin 2.54 mm male header, unsoldered
Getting started
- Plug in a Qwiic / STEMMA QT cable, or solder the header and wire VIN, GND, SDA and SCL
Compare
Which long-distance I²C option?
| Differential I²C Extender (this board)This board | ET-C07 Isolated I²C Bridge | ET-A02 TCA9548A I²C Multiplexer | |
|---|---|---|---|
| What it does | Runs Qwiic sensors up to ~30 m over twisted pair | 2.5 kV isolation between your MCU and an I²C device | Eight separate I²C channels, each with its own Qwiic port |
| Interface | — | — | I²C 0x70 (0x70–0x77 via jumpers); Qwiic in/out +… |
| Best for | Sensors across a room or greenhouse | Sensors on motors and drives | Several sensors with the same address |
| Price | 39 AED | 25 AED | 22 AED |
Downloads
Documents and design files
Need a custom version of this board?
Different connector, size or sensor? We design and build custom variants.