I'm experimenting with a couple of VL6180x distance sensors on breakouts (http://www.ebay.com/itm/172823051918, the blue ones).
Because the sensor resets its i2c adress when the power is removed, and because I want to use more than one, I need to be able to set the desired adress after boot.
My idea to solve that was to simply turn on the VIN to the sensors one after the other, and set the adress before the next one turns on. Unfortunately it seems like the sensors get power somehow even without any VIN connected. I'm guessing it's through the pullup resistors on the i2c bus.
How can I solve this? Do I have to add something to break the i2c bus connection together with VIN, or are there other better ways?
(Since the project they're intended for have limited free space, I'd prefer a solution with a low component count)
Best Answer
So that's just a breakout board for this? http://www.st.com/content/ccc/resource/technical/document/datasheet/c4/11/28/86/e6/26/44/b3/DM00112632.pdf/files/DM00112632.pdf/jcr:content/translations/en.DM00112632.pdf
If so, you can hold the GPIO0 input (the 0 on the breakout board) low to put the chip into a reset state. This means you will need to dedicate an I/O line to each board, but that way you can bring them up one at a time without doing crazy things to the I2C bus itself.