I have a light sensor IC.
I have 2 questions:
- The I2C Lines is connected between the microcontroller (3.3V domain) and the light sensor IC. The microcontroller is placed on a PCB and the light sensor is placed on a separate PCB. Both PCBs are connected by a cable of length 30cm.
In this case, is it correct to place the pull ups of the I2C near the microcontroller on the microcontroller PCB, or should I place it on the light sensor PCB? As far as I have read, the pull-up resistors should be placed close to the master and hence I am thinking it should be placed close to the microcontroller. Please confirm.
- I am not planning to use the INT pin. INT is an open-drain output pin from the datasheet. I don't want to use that pin because it will help in one connector pin less. So, in order to not use the INT pin, what should I do? The datasheet doesn't recommend what to do with unused pins. So, what should I do? As far as I know, since the INT pin is an open drain pin, can I leave it floating. Please confirm.