OK - I have removedI wouldn't include the LED indicator. The MOSFET modules have an LED on the output side.
It seems I can connect to the terminal on the MOSFET - is this best?I'd also tidy up the wiring on the MOSFET module output. It's not clear from the drawing.
Should I have level shifters between the Pi and PCA9685? To get from 3.3V I2C bus to the 5V CMOS?Google is increasingly not your friend when it comes to decent search results! That's a 7-year old post, and times have changed. Nowadays, you can certainly get MOSFETS which can operate with less than 3.3V gate voltage. Or, as you suggest, you could power all the PCA9685 from 5V (which may mean one less power supply); however you then ideally need level shifters to convert the Pi's 3.3V I2C bus to the 5V CMOS levels of the PCA9685. (Or you could just pull the I2C bus up to 3.3V and use direct connection - you may well get away with it, but you could also get obscure problems.) Personally I somewhat prefer powering the PCA9685 from 5V - if nothing else, it gives you a wider choice of MOSFETs.
Statistics: Posted by cairanvanrooyen — Thu Dec 26, 2024 2:39 pm