3.3V I2C from BS2px

jokerswild

I'm trying to control a 3.3V I2C device from BS2px and i have a few questions.

Only need to use I2COUT command.

Can i use a couple of resistors to make a voltage divider to reduce the 5V SDA and SCL lines to 3.3V and would i put the pull-up resistors on the 5V side of the divider?

Is the max pin current draw the same as normal when using I2C commands?

Cheers.

LoopyByteloose

You may not need to make a voltage divider, just insert the right sized resistor between the two.

The Art of Electronics has nearly a whole chapter explaining how to match up devices of different voltages and different generations of productions.

It would help if you could specifically mention what device you want to use. It might even work at 5volts without any resistor.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)

······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Jon Williams

The Philips I2C specification shows how to interface 3.3v and 5v I2C components.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Jon Williams
Applications Engineer, Parallax

jokerswild

Thanks for the help guys!!