OFN Modules are quickly becoming popular as a user input device in many smart phones as a replacement for trackballs, which are subject to mechanical wear and tear.
OFN technology is very similar to the technology used in optical mice, and movement across the sensor can be read by any microcontroller using I2C communication.
- Built-in center select button
- Onboard red LED which lights when finger movement is detected
- Easy I2C communication interface with virtually any microcontroller
- Onboard voltage regulator conditions I/O to 3 V max for compatibility with 3.3 V devices even when 5.5 V is supplied to Vdd
- User-selectable 500 to 1000 counts per inch (cpi) resolution
- User-definable 0 or 90° module orientation
- Breadboard-friendly package with 0.1" pin spacing
- Power requirements: 3.3-5.5 VDC; 25 mA active, 1 mA standby
- Communication: Two-Wire Serial I2C (400 kHz)http://forums.parallax.com/content.php? ... Sneak-Peak
There is a .pdf online with more information available.