Two i2c slaves connected to nrf52832

[Manoj Hiwarkar]

Dear Sir,

I want to access two slaves viz. MAX30205 & LIS3DH by using nrf52832. The problem is, as per the datasheet the values of the pull up resistors required by both the slaves are different. Max30205 needs 4.7k & LIS3DH needs 10k. So what values of pull up resistors shall I put on the i2c bus ?

Eagerly waiting for your reply.

Warm regards,

Manoj Hiwarkar

[Stian Røed Hafskjold]

What is the bus speed you are going to use? You will probably be fine with just the internal 13k pull-up on the nRF chip for lower speeds.

[Stian Røed Hafskjold]

It is hard to give an exact answer to this because it depends on several factors. The driver strength on each of the slaves, the line capacitance, etc.

You should check with a scope to see if the driver strength on the slaves are good enough to drive the pull resistor down, and that the pull resistor pulls the line back up again fast enough, for both of the slaves.