Twenty minutes in, the I²C sensor stops answering
Illustrative image: khezez | خزاز on Pexels
Fictional engineering case. No real company or reader is being quoted.
This week’s problem
A small UK design team has a sensor controller that passes production test and behaves normally from a cold start. After around twenty minutes in its enclosure, communication with one I²C sensor becomes intermittent. The firmware logs missing acknowledgements, but swapping the sensor and slowing the bus have not removed the fault.
The team has checked the supply rail with a multimeter and found nothing obvious. The problem appears sooner in a warm chamber and disappears after the board cools. They want to know which measurements would separate a timing, signal-integrity, assembly or thermal component fault without changing several variables at once.
Next week, Troubleshooter will set out a structured test sequence and explain what the fictional team found.
Readers can submit their own problem through the Troubleshooter page.
