FRNBv2 is dead. Long live FRNBv3!

Christoph Mair ml at chonyota.net
Mon Feb 28 23:41:59 CET 2011


Dear list,

unfortunately the compass chip included in the FRNBv2 is no longer available. 
Thus, I am not able to produce the FRNBv2 anymore. For those of you who still 
want the board I am designing the FRNB version 3. The discontinued chip 
HMC5843 will be replaced with it's successor HMC5883 which is slightly smaller 
and therefore requires a new PCB layout.

A new feature of the FRNBv3 will be the support for different supply and I/O 
voltage levels. The sensors need at least 3V to work properly while the 
voltage for the I2C bus can be as low as 1.8V. 
This allows you to connect the board to your Freerunner (using 3.3V for supply 
and I/O) as well as to other hackable devices such as most devices using a TI 
SoC (Beagleboard, Pandaboard, AI SmartBook ect.).

The top side of the new board which contains all sensors is already finished. 
For the bottom side I'd like to hear your opinion: what should be included?

Currently, the board contains the following parts:
Top-Side:
- HMC5883 Compass
- ITG3200 Gyroscope
- BMP085 Pressure sensor
- BMA180 Accelerometer (new!)

Bottom-Side:
- MPR121 Touch Sensor
- 38kHz Fixed Frequency Oscillator with ~10% duty cycle for IR remote
control applications. I hope this works better than the last approach.
- TCA6507 7 channel LED Controller
- I2C-Level-Shifter to connect additional electronics with I/O voltages
bewteen 1.8 and 5V

And there is still some space left (about 50mm²) which I'd like to fill up with 
other nice gadgets. Suggestions?

Best Regards,
  Christoph



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