Hi there, I was wondering if you all could give me some feedback on my latest hobby electronics project.
I thought it would be fun to try to replicate Epcot's jumping water fountain at a very small scale, so I bought some cheap pumps and have been designing a microcontroller + power mosfet board that should be able to PWM 12V@350mA * 8 through 0.05 Ohm FETs. The board is 50mm^2, designed to fit inside a Hammond 1593K box, includes a buck regulator to provide 3.3V to a STM32 microcontroller, RGB LED in the corner, button, clock crystal, 4 JST PH connectors on either side plus a green terminal block for DC input. Most complicated thing I've attempted so far. How do you like it?
I think it will probably be fine to route the input voltage around the outside of the board. The board has a virtually unbroken ground plane.
Not sure about the 750mA polyfuses on each set of 4 outputs. Better than nothing but the trip current of 750mA @ 12V is a decent amount of power. Yes I'm currently living dangerously without reverse polarity protection.
Think I can get away without big caps to bypass the motor outputs and just let the them take the ripple?
Will be interesting to listen to the buck regulator on an AM radio. How do I know whether it should it have a common mode choke, a ferrite bead, or some other kind of filter?
Loving KiCad's new push-and-shove router by the way.
Thanks,
D