I’m creating a Kicad PCB design to replace a breadboard circuit I’ve built that helps drive three stepper motors controlled by an ESP32, TMC2208 controllers and a 4x4 keypad. The breadboard setup works well. I’m now on to designing the ground fill zone and reading tutorials etc I’m become confused:

Do I have one zone to connect all the ground pads on the ESP32, controller, motor supply and all?
Or one zone for the ESP32 and another zone for the motor supply ground with one connection between these two ?
Or something else ?
And why?
Any help would be much appreciated.

 

Small voltages will occur in the motor ground wire created by the motor switching currents. It is better to have separate ground pads for the controller and the motors so that these voltages do not affect the controller. Each ground pad should be connected to the supply using a separate wire.

 

Thanks Kieth, I’ve read similar comments else where and its what I don’t understand I guess. The four motor coils connect to the controller as does the ESP32 5V supply (Vdd) and its ground, as does the motor 12V supply (Vmot) and its ground via a capacitor.
So if I understand correctly you mean that that the motor ground (GND1) fill zone should be separate from the controller and ESP32 zone (GND), and so the two grounds are connected through the controller. And in the circuit attached GND and GND1 would remain separate
Yes?

 

Yes, there should be a separate wire connection to the power source negative terminals from each negative supply connections on the microcontroller supply and the motor controller. The 5V and 12V negative supplies should be connected directly at the source.

 

Thanks for the clarification much appreciated

 

Be careful not to do what they did in my WiFi-equipped microwave... The antenna of the ESP8266 sites right on top of a ground shape. The resultant RSSI/sensitivity is terrible! Take a look at: