I’m working on my first, very simple PCB with kicad. It’s supposed to replace the breadboard based prototype of a DIY ambilight. The prototype consists of:
- Arduino Nano
- WS2801 LED strips
- Resistors between Nano and LEDs for data and clock lines
- Decoupling capacitor after the 2.5mm Barrel Jack
- 5V 4A PSU (DC)
Power is supplied to both ends of the LEDs. Controller and LEDs are connected through two female 4-pin JST cables.
The major (intentional) difference from the prototype is the fuse. The LEDs need 2.4A in the worst case, connectors and wires to/between the strips are rated for 3A. So I thought about using a 2.5A or 3A slow-blow fuse like this. The current track width for power and ground should be large enough for 4A (assuming 30° temperature rise) to leave some room for more LEDs.
I am a complete beginner, both in terms of circuits and kicad. I expect that parts of my PCB are … well, suboptimal or wrong But I’m happy to learn from my mistakes. I started with Fritzing and switched to kicad shortly afterwards, which I really like so far.
Any hints regarding obvious mistakes or possible improvements would be highly appreciated. Things I’m still thinking about:
- The placement of the capacitor.
- The mounting holes. Should I rather use those with a pad to prevent the screw heads from touching the power plane?
- From what I have read, choosing the right fuse seems like a science in itself.
Thanks in advance,