SPECIFICATIONS

Brand Name: NONE

High-concerned chemical: none

Origin: Mainland China

MPR121 Module Capacitive Touch Sensor Key Induction Keypad

Size: 48mm*78mm

Product Introduction

This MPR121 capacitive keypad adopts MPR121 chip with 12 touch sensing pads, featuring I2C signal output. The module is designed with four mounting holes, which can replace traditional physical buttons to build input control systems. Refer to the attached sample code to quickly realize keypad reading function.

Note: This module outputs 3.3V level signal. It cannot be directly connected with 5V single-chip microcontroller mainboard. Please use level conversion module or 3.3V compatible control board for matching use.

MPR121 Touch Keypad Dialing Demo Code

Author: Jim Lindblom

Brand: SparkFun Electronics

Creation Date: January 6, 2010

Open Source License: CC-SA 3.0

Function Introduction

Realize telephone dialing function via MPR121 touch pad, trigger corresponding output of numbers 0-9, asterisk and pound sign by touching different areas.

MPR121-Breakout-v12 Proximity Capacitive Touch Sensor Controller Development Board

This is a dedicated expansion board based on Freescale MPR121QR2 chip. The MPR121 is an I2C-controlled capacitive touch sensing controller, which can independently drive up to 12 touch electrodes and simulate the 13th sensing channel. Meanwhile, it is equipped with 8 LED drive pins, which can be used to control LED indicator lights when not used as touch detection pins.

Board Design Features

Four default closed jumper caps are reserved on the back of the board;
The address jumper connects the ADD pin to GND by default, and the factory I2C communication address is fixed at 0x5A. To modify the address, disconnect the jumper first;
SDA, SCL and interrupt pins are externally connected with 10K pull-up resistors via jumpers, which can be cut off and removed if pull-up function is not needed;
No built-in voltage stabilization circuit on the board, the applicable input DC voltage range is 2.5V ~ 3.6V;
The VREG pin is grounded with 0.1uF capacitor. Without hardware modification, it does not support low voltage working mode of 1.71V~2.75V.