Help with PCB project - ESP32 Drone

[Samuel000]

Hello, I would like to create a drone based on ESP32 with 4 DC motors and MPU6050. I added ch340c to be able to upload the code to esp and USB-C. Can anyone check if the pcb is designed correctly, what should I change or add, if the paths are correctly routed and connected to the correct pins?

https://easyeda.com/editor#id=99cb6e292 ... 3a35c57914

Motors I used:
https://pl.aliexpress.com/item/32732965 ... pt=glo2pol

[username]

Couple things.

#1) I see that VBAT & VUSB are tied together. Not sure your plans, but If the battery is plugged in at same time USB is something bad will happen.
#2) I see you have no 0.1uf caps to GND on the EN or GPIO0 lines, Neither pullups to +3.3v.
I have seen far to often not doing this typically causes problems.
#3) C8 is to far away from U6. You should have that as close to the regulator as you can. You should also have a larger cap in parallel with it something like >=10uf. Check the data sheet. You should also have another one for the input as well. Personally, I would use something like a few 10 or 22uf on the input because your motors are ran off the same supply. your gonna get some noise on the power rail with those motors on it so you should have a way to filter that to help the regulator.

[Samuel000]

Thank you for your answer, it is very helpful.
1) The idea is that the USB will only be used to upload the code and the battery will be disconnected during this time, can it stay like this or should I change something?
2) I added resistors and capacitors to EN (R21 -> 3.3v, C15 -> GND) and GPIO0 (R20 -> 3.3v, C16 -> GND)
3) I moved C8 closer to U6, added C17 (10uF) next to it, and added C18, C19, C20 (22uF) at the regulator input, should I replace C7 (100nF) with something else or can it stay? And in the case of CH340C, should I add an additional capacitor next to the 3.3v pin or are these enough?
Apart from that, is there anything else I should change?

[username]

1) The idea is that the USB will only be used to upload the code and the battery will be disconnected during this time, can it stay like this or should I change something?

Then you are ok.

2) I added resistors and capacitors to EN (R21 -> 3.3v, C15 -> GND) and GPIO0 (R20 -> 3.3v, C16 -> GND)

looks good

3) I moved C8 closer to U6, added C17 (10uF) next to it, and added C18, C19, C20 (22uF) at the regulator input, should I replace C7 (100nF) with something else or can it stay? And in the case of CH340C, should I add an additional capacitor next to the 3.3v pin or are these enough?

looks good, Personally I am a strong believer to put 0.1uf caps at the power pins of every chip. So if your up for it I would do it.

Apart from that, is there anything else I should change?

Seems the silk screen for M1-M4 +/- is flipped.
Not sure how much current those motors take but the trace width from Q3-Q6 to M1-M4 seem very thin. They should at least be the same as the VBAT width if not larger. Also I would triple up (parallel) your vias for the VBAT to M1-M4. You dont want to wind up starving the motors for power through just one small via

[Samuel000]

Thanks for your advice, thinking about it, it seems very wise. Tomorrow evening I will check all connections to make sure they are correct and place an order for a PCB. If anyone has anything else to add, please write.

[Samuel000]

I will also add that I added a capacitor to the CH340C, increased the track width to 0.62mm, the same as the vias, and added 3 vias on the power supply connection to the motor, as you wrote earlier.

[Samuel000]

Hello. I assembled the PCB and I have a problem, I have soldered the parts to M1 and when I measure the voltage with a meter, while PWM is at 0, the voltage is 3.44v and when PWM is at 255 it is 3.27v. Does anyone have any idea what it could be or something? Is this the case with the connection or maybe the mosfet is bad?