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I picked up a couple of these: https://smile.amazon.com/gp/product/B0814MKZVW/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1 and am trying to do a basic circuit.

First, maybe if you could give me the proper name for the circuit I am trying to build, that would help so I know what I am looking for. Since this isn't with a 555 timer, I tend to get lost in some of the other responses to similar questions.

Ok, so using a 5V in, I was able to check with an LED and the PWM is working properly, so I hooked it up to a breadboard with an LED light strip to visualize the output power.

I have a wide assortment of transistors from tearing apart TVs, power supplies, amplifiers, even one an electric city train, so not just the small ones. Most I have so far seen are NPN or NFET. I tried laying it out with the following transistors:

https://datasheetspdf.com/pdf-file/678667/Savantic/D998/1
https://datasheetspdf.com/pdf-file/660793/InfineonTechnologies/11N60C3/1
https://www.mouser.com/datasheet/2/149/KSA916-66917.pdf

enter image description here

I am sorry for the artwork, I am not great at reading schematics and wanted to make sure I conveyed what I was doing properly. I am getting the 110V DC from a bridge rectifier and the 5V from a wall plug transformer. To test I have the PWM at 2Hz and 10% duty cycle. Sometimes I can see where it looks like it is almost working, I can see a pulsing in the LED strip, but I am not sure if it doesn't have enough to drain the internal capacitor on the transistor, because it stays on all the time, just flickering.

I am not sure what I am missing here, but I hope to be able to drive a variety of gadgets using the same type of circuit once I understand what I am doing wrong. Currently I would like to drive an ultrasonic inductor and 1-5HP motors (not at the same time, those are just the two projects).

I assume to drive something the size of the IGBT (CM400DU-12F https://www.mitsubishielectric.com/semiconductors/content/product/powermodule/igbt/nfh_series/cm400du-12nfh_e.pdf) I will need to step up my input voltage to maybe 24V, but the rest of the schematic would be exactly the same, right?

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  • \$\begingroup\$ It looks like the NPN darlington transistor symbol in your sketch is upside-down. The emitter (pin with the arrows) and the collector (pin with the junction dot) need to be swapped. Also, there must be a resistor between the PWM and the transistor's base. Finally, there must be a diode across any motor connected (not LEDs), connected in reverse, to prevent the motor from making high-voltage spikes which will destroy the transistor. Be careful around that 100VDC; anything over 50VDC is considered hazardous. \$\endgroup\$
    – rdtsc
    Commented Nov 30, 2020 at 22:18
  • \$\begingroup\$ Beware! The result of rectifying 110VAC is generally not 110VDC. \$\endgroup\$
    – Math Keeps Me Busy
    Commented Nov 30, 2020 at 22:48

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