I cannot connect pads

Hi, find attached my pcb, I cannot connect some pads. The track just goes around the pad or I cannot even select the pad

meditation_v1.kicad_pcb (229.2 KB)

I would guess that you are referring to pin 10 of U1. If not, please specify.

You have a hole under U1 that intersects pin 10. For this reason, you are not allowed to route to it without allowing DRC violations.

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Thanks @Seth_h, yes, I wasn’t able to connect that pin, thanks for make me notice the hole.
The rest of the pins I cannot connect are:

  • Pin 1 of J3
  • 5.0V_OUT between R5 and C3
  • GND of C4

If you switch to “Highlight collisions” mode in your Interactive router settings (right click while routing), you can see what element is preventing the connection.

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The net clearance of your 5 V net(s) is too high to allow connection. If you really require this much clearance then you need to select another connector and larger packages for the capacitor and resistor. If this clearance is set this high by accident then reduce it.

Ye , I just figured out that. I learned in a tutorial that power tracks should be 0.3mm. I guess for the resistors and capacitors I can just change the size, but how can I do with the micro usb connector (J3)?

It’s not that simple. It’s about resistance, power loss, generated heat and dissipated heat. 5mm long 0.15mm track generates as much power loss (and heat) as 10mm long 0.30mm track. You can try it with KiCad’s PCB calculator.

The track or a part of it just can’t be allowed to get too hot, and whether it does or not depends on the surrounding temperature, other tracks and especially zones and planes around it (even of different nets), other metal parts and components, air flow around it, the time over which the high current flows through it etc.

A narrow but short track segment isn’t usually a problem near a connector. It’s supposed that the track gets wider as soon as there is space. Some of the heat will of course flow to the metal parts of the connector and even to the cable attached to it.

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Was that regarding clearance or track width? Because right now your problem is with the clearance which is determined by the manufacturers capabilities and possibly by your required isolation rating. (I however doubt that a 5V supply will need such a huge clearance.)

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