TL;DR: Please make sure my schematic and board design won't blow up on me. GitHub Repo if you're feeling extra thorough.

Project overview

I am trying to create an Arduino based Bluetooth RGB led controller, but larger-scale than most. I'm planning on having 25 meters of (common-anode) 12v led strips, which means about 300 watts of lights. I'm using a scavenged Corsair CX430M for power, and as a housing for the Arduino. My proposed schematic I've already programmed the ESP32 brain and set up the circuit using a single RGB led with transistors instead of MOSFETs, and resistors between the emitter and ground. I don't know how closely that performance will translate to my PCB setup.

Main Schematic concerns

1: I've read that the 2 resistors before the MOSFETs will reduce accidental switching from trace capacitance or something. Regardless, If something is overkill or dangerously underkill, please let me know.

2: I've selected NCE3080KA MOSFETs. I think I can use just about any MOSFET, but if this one is wrong for some reason please let me know. Right now the PWM is set for a 5kHz, but I'm pretty sure I go much lower. GPIO voltage is 3.3.

Proposed PCB Layout sorry for the bad screenshot. I'm not sure what layers should be visible. The full board design is available here

Main PCB concerns

1: The PCB will be passing up to maybe 30 amps of current. To mitigate the issue, I added a stupid amount of vias to help sink heat and left the entire bottom solder mask-free, but I'm not sure if that's sufficient.

2: Manufacturability. Is something wrong with my design that just won't work, or can't be made for some reason?

**Edit 1: ** @WesleyLee pointed out that I switched the mosfet drain and source. Updated pictures to reflect changes.

  • \$\begingroup\$ What’s your Vcc voltage? What is your switching frequency? \$\endgroup\$ – winny Jul 19 at 16:21
  • \$\begingroup\$ The biggest problem you have is that you are feeding 10A of current into long LED strips. The traces and wiring on those strips aren't usually made for high current. You may find that the far end of each strip is darker than the near end - or doesn't light at all. Worst case, the traces burn off of the LED strips from the high current. \$\endgroup\$ – JRE Jul 19 at 16:21
  • \$\begingroup\$ Manually carve up some copper clad to build one copy of the amplifier and try it. You should probably re-place things so that the FETs are in a different area surrounding by copper pours, and the through hole ESP is elsewhere. I'd even consider making distinct little PCBs handling one channel each, at least for the initial test. \$\endgroup\$ – Chris Stratton Jul 19 at 16:22
  • 1
    \$\begingroup\$ I think you flipped the Drain and Source. \$\endgroup\$ – Wesley Lee Jul 19 at 16:58
  • \$\begingroup\$ @winny, LED voltage is 12V. Arduino runs off the 5v rail. the switching freq is configurable, but I was planning on 5kHz. \$\endgroup\$ – Benjamin Kittendorf Jul 19 at 17:05

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