We have a Wii balance board pressure sensor and were wondering how we could connect this sensor to an Arduino board.
On the circuit board (see picture) of the Wii Balance Board are Japanese characters printed, only those are pointing out which color there must be. The problem is, most pressure sensor examples of the Arduino are with 2 cables, but the Wii pressure sensor got 4 cables. So which cable is for what?
It has two TI ADS1222 2 channel Serial ADC converters, for four sensors total.
The two smaller ics labeled TI 93 DBA3/DBAQ are probably opamps (can't find the part) but they should trace out to the ADC converters. Most likely, LMV932s, dual low voltage high quality opamps, but they don't match the suggested topcodes.
The four pin connections are Strain gauge wheatstone bridge connections.
The topmost (White) connection for each of the four bridge connections is the ground; relative to this, the two middle connections should be at 1.2 VDC, and the bottom should be at 2.7 VDC
The entire board acts like a standard wii remote, with a standard i2c wii balance board extension/accessory. It can be accessed via Bluetooth, or you could maybe tap into the i2c lines as well.
See http://wiibrew.org/wiki/Wii_Balance_Board for the bluetooth/hid descriptions and information.
Frankly, the bluetooth way is the easiest. Unfortunately, it's not as easy as the Wii Nunchuck being a simple i2c device with a connector.
I know this is a very old topic, but it looks like there is no other resource on the internet. As Peter said, it looks like the smaller IC is a OP2333. I've soldered on the OUT A and OUT B pins of this IC wires, which I connected to the analog inputs from the arduino (A0-A3). I also took a 3.3V from the board and connected it to the reference pin for the ADC of the arduino. This will work and you get usable values.
