4x4 Matrix Keypad with I2C Adapter, 2-Pack

A heavy-duty 16-key keypad with an I2C adapter that cuts its wiring from eight GPIO pins to two. Two complete sets in the pack.

Highlights

• Eight pins down to two. The adapter reads the keypad over SDA and SCL, and other I2C devices can share the same wires.
• Rigid keypad. Moulded ABS frame with 16 raised keys: 0–9, A–D, * and #.
• Plug together. The 8-pin header is soldered to the keypad at the factory and plugs into the adapter socket.
• 3.3V or 5V. Runs at your board's logic voltage, no level shifter needed.
• Both on one bus. Adapters ship at 0x20; bridge the A0 pad on one (soldering required) to move it to 0x21. The pads cover 0x20–0x27.

In the box

• 2 × heavy-duty 4x4 keypad, 8-pin header soldered on
• 2 × I2C adapter with an 8-way socket

Specifications

• Keys: 16 (4 × 4)
• Actuation force: 160–180g
• Contact resistance: under 100Ω
• Supply: 3.3V or 5V
• I2C address: 0x20 as shipped, 0x20–0x27 by pads

Works with

Any board with I2C in the Arduino IDE, including the ESP32-S3. The open-source I2CKeyPad library is in the Arduino Library Manager.