The Grove 12 Key Capacitive I2C Touch Sensor V3 (MPR121) is a multi-channel proximity capacitive touch sensor. It's a 3-in-1 module with the following features: Capacitance Sensing, Touch Sensing, and Proximity Sensing.
Capacitance Sensing: This module uses a constant DC current capacitance sensing scheme. It can measure capacitances ranging from 10 pF to over 2000 pF with a resolution up to 0.01 pF.
Touch Sensing: Once the electrode capacitance data is acquired, the electrode touch/release status is determined by comparing it to the capacitance baseline value.
Proximity Sensing: One new feature of the MPR121 is the near proximity sensing system. This means that all of the system’s electrodes can be summed together to create a single large electrode.
Based on Freescale MPR121, this sensor has 12 completely independent electrodes with built-in autoconfiguration. Thanks to the I2C interface, you can detect all 12 electrode signals with only one Grove pott and the I2C address is hardware configurable from 0X5B to 0X5D. This also makes it possible for multiple Grove -12 Key Capacitive I2C Touch Sensor V3 (MPR121) to be used together for channel expansions in a single system, you can build a touch system that contains max 36 electrodes.
- Powerful functions: Integrated capacitance sensing, touch sensing, proximity sensing, and Integrated independent autocalibration for each electrode input
- Hardware configurable I2C address: I2C interface, with IRQ, Interrupt output to advise electrode status changes
- Drive the LEDs: 12 electrodes/capacitance sensing inputs of which 8 are multifunctional for LED driving and GPIO
- Safe handling: Add two more GND pins and expand the gap of pins for safe handling
- Grove compatible interface: The product ensures "Plug and Play" and could be versatile for various applications of Grove
- PC Peripherals
- MP3 Players
- Remote Controls
- Mobile Phones
- Lighting Controls
|Dimensions||60mm x 20mm x 7mm|
|Operating Voltage||3.3 V / 5V|
|Operating Temperature Range||- 40°C to 85°C|
|Storage Temperature Range||- 40°C to 125°C|
|Capacitances Range||10 pF to over 2000 pF|
|I2C address range||0x5B,0x5C,0x5D|
|Default I2C address||0x5B|
Figure: Device Schematics