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I've bought this sensor, and I'd like to connect it to Raspberry Pi (unless I manage i2c on dagu minidriver). The spec on the sensor say:
How does it relate to the output voltage it produces? Is my intuition right that I can plug it to rpi 3.3V line and it will operate happily producing 3.3V level logic for rpi?
Yes, in this case that is true.
The SCL and SDA level shifters pull the I²C bus high bits up to this level.
Which means the 1 bit will be the same as the VIN voltage. So 3.3v input = 3.3v HIGH Bit for I2C
It also supplies a 3.3v regulated voltage separately on VDD, but only if the voltage is higher tan 3.3 but when its LESS than 3.3v you actually supply the voltage into VDD. Pretty confusing but allows for flexible prototyping. In your case supply 3.3v to VIN and you will be OK to connect the pins directly to Pi.
Looking at the schematics though, the circuit is always powered by 3.3v - The level shifters on I2C are responsible for using VIN as reference to produce I2C at the requested VIN voltage.
