I2C sensors power level

[unroller]

Hi,

I found that LeJOS uses TYPE_LOWSPEED_9V constant to specify 9V power level for some I2C sensors. But I could not find any documentation that describes the necessary power level for these sensors.
I tested HiTechnic Accelerometer sensor using TYPE_LOWSPEED_9V and TYPE_LOWSPEED and found that it worked in both cases.

What advantages of using 9V power level instead of 5V? Is it safe to use HTAccelerometer sensor in HIGH_SPEED mode using 9V power level (by specify TYPE_LOWSPEED_9V)?

Thanks

[gloomyandy]

It all depends on the sensor, for instance the Lego Ultrasonic sensor requires 9V to operate correctly (it uses the 9V supply in a voltage doubler circuit to driver the ultrasonic emitter). I suspect that all certified Lego devices will be safe with a 9V supply. As to other devices best read the documentation. The safe option is to try it with 5V if it works stick to that...

Andy