nRF5340 I2C driving strength tuning

RE: nRF5340 I2C driving strength tuning

Kenneth — Tue, 30 Dec 2025 15:22:27 GMT

Usually using smaller pull up resistors or add some capacitance can do the trick. Though I was not aware there was also a requirement that fall times must be larger than a minimum value, I was only aware there were some max values that is must be lower than.

Kenneth

RE: nRF5340 I2C driving strength tuning

Poki Huang — Tue, 30 Dec 2025 01:51:28 GMT

Hi Kenneth:

Sorry for confuse

I mean I2C SCL falling time is 5.87ns, little shorter than spec. 6.54ns (20*1.8/5.5)

This measurement is by standard drive setting, and high drive setting will cause the falling time shorter, but I need this timing longer than 6.54ns, not use more stronger drive like extra high drive

So I want to know if any other register can tune I2C SCL drive more weak to let SCL falling longer

Thank you

Poki

RE: nRF5340 I2C driving strength tuning

Kenneth — Mon, 29 Dec 2025 12:54:10 GMT

Hello,

Some pins also have extra high drive, ref: https://docs.nordicsemi.com/bundle/ps_nrf5340/page/chapters/pin.html

Kenneth