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I just made two LED panels each consisting of two colors of LED strips.

They are wired in a way that allows it to be powered from a 19V (3.42A) laptop power supply:

enter image description here

(This image shows only one panel.)

These are 60 SMD3528 per meter LED strips.

How can I drive the two colors (separately) at at least 10kHz from an Arduino MKR WiFi 1010 (3.3V)?

I already found that I should drive them with an IRF520 or IRF630 MOSFET, but apparently they will not be able to handle that high frequency. I need the high frequency because I am going to be using those panels for photography and filming.

What would you suggest?

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  • \$\begingroup\$ Welcome! ”IRF520 or IRF630 MOSFET, but apparently they will not be able to handle that high frequency” Both would switch your load happily at 100 kHz given sufficient gate drive. My guess is that your board lack the latter. Please clarify with a schematic what’s going on between the MCU and your string of LEDs. \$\endgroup\$
    – winny
    Jan 30 at 12:23
  • \$\begingroup\$ @winny That's exactly what I'm trying to know, for now I haven't bought any MOSFETs or anything and I haven't tested anything. So you're saying that both IRF MOSFETs will handle 100kHz? I had seen that there was a limit around 1kHz or so somewhere... Can you confrm that I could use those for high frequency? \$\endgroup\$
    – tarneo
    Jan 30 at 12:28
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    \$\begingroup\$ Please simulate them and/or hand calculate how much gate drive current you need to have at 10 kHz to have acceptable switching losses. If they won’t, there are thousands of different MOSFETs available. Pick the right one for the job. \$\endgroup\$
    – winny
    Jan 30 at 12:41
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    \$\begingroup\$ The MCU will not be able to drive the FET directly at these speeds, you need a FET driver circuit. You can buy ICs that do this, something like a UC3709N (see figure 2). \$\endgroup\$
    – Mattman944
    Jan 30 at 13:25

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So actually, using an N-channel MOSFET was the way to do it. A few things to note here:

  • I needed 5V to drive my MOSFET (IRFZ44N), so used a 3V/5V 2-way voltage shifter (doesn't need to be 2-way, it's just what I had handy).
  • As an N-channel MOSFET will drive the ground, you have to think about how you want to connect your panels to your control unit. For example, BNC connectors that have the outer pin connected to the panel will just make all the panels be on at all times...
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