Every time I try to look for a 20 amp or higher voltage regulator all I find is voltage regulators meant for cars or not laser related purposes. I am thinking of making something similar to a video made by styropyro, instead of using complicated custom circuitry could I use something like an automotive voltage regulator as a diode driver? this is what I am trying to recreate:
Why not just use LM338 regulators configured as current limiters like drake did ?
Also you don't need 20 amps, for a nubm31 you have 4 strings of 5 laser diodes in series and you don't want to drive those 4 strings in parallel because any inconsistencies could have one string pulling more than another, so just use a lm338 for each string limited to 4.0A or how ever hard you want to drive them or connect your 4 strings in series and use a single current regulator ( you will need more Vin of course if you do that ) and if you don't want to make one you can buy this >>> use this > CLCK THE OPTION AND SELECT " PCB DRIVER "
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It should go without saying but I will say it, you need the proper laser safety glasses to attenuate the wavelength of laser that you are working with or else you will likely go blind, so if you don't already have them get some of THESE
