Hi, I am working on an old project at the moment that had some issues and I think I have found that the reason is weak pull up resistors on the SCL & SDA lines. Now, one I2C sensor is not accessible and has 1K pull ups on the board that I cannot get at to change. Am I right in thinking that I cannot…

Increasing I2C pull-ups via additional resistor?

system December 11, 2012, 9:07pm 5

I guess I'm expecting the pull up value needs to be closer to 4K7 rather than 1K

Typically 4.7k, though I have used 220 - 10k.

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