The MPR121 is the second generation of sensor controllers following the initial release of the MPR03x family of devices. In addition to Freescale's second-generation capacitive sensing engine, the MPR121 also improves internal intelligence. Key enhancements include increased number of electrodes, hardware configuration of I2C addresses, a new debounce filtering system in addition to the original filtering, and a fully independent auto-configurable electrode. The device also adds a 13th virtual analog electrode that powers up all connected electrodes simultaneously for close proximity detection of touchpads or touchscreen arrays.
characteristic
• 1.71 V to 3.6 V operating voltage
• 29μA current, 12 electrodes monitored, 16ms response time, IRQ enabled
• 3μA shutdown current
• 12 electrodes
• Continuous and independent automatic calibration of each electrode input
• Each electrode can be set with independent touch and release thresholds
• I2C interface, IRQ output to notify electrode status changes
• 3 mm x 3 mm x 0.65 mm 20-pin QFN package
• Provides up to 8 LED driver functions
• Operating temperature from -40°C to +85°C