I have 5 pieces of 100W LED chips but customs won't let me import 5 pieces of drivers to power them unless I pay a ridiculous sum. They are 100 Watt LED chips rated 30-35V @ 3A.

I cannot find 36V LED drivers locally, So I need to choose a 400 to 600W LED driver and use several DC-CC converters.

There are 12 to 48 Volt drivers available; which voltage would be a better choice? Should I go for a lower voltage driver (12V or 24V) and step-up converters or higher voltage driver (36V or 48V) and step down converters to obtain a more reliable and efficient system?

My gut tells me to go with a 36V-600W driver and add 5 pieces of DC buck converters but I am not sure if it would be a long term & reliable solution. Can I succesfully power these LEDs using this DC converter?


1 Answer 1


If you have a 600W, 36V LED driver circuit available to power 5 100w, 30-35V LEDs, why would you then need to use voltage converters?

LEDs actually don't care if you apply a source to them that is capable of an open-circuit voltage over their rated voltage; they only care how much current you allow through them.

This means that all you really need is a FET for each LED & a resistor/zener diode to set the current passed by the FETs in order to drive your LEDs from that 600W, 36V driver (or from any other 35-38V source that's capable of pushing the needed 15A). Something like this should work great:
CC LED Driver x5

* Zener Diode - NZX3V3B,133
* Resistor - 2K2, >=0.25W
* Heat Sink - 530002B02500G
* Total Bill Of Sale < $25USD

  • \$\begingroup\$ Isn't this branch voltage regulation and not current regulation? \$\endgroup\$
    – VoteCoffee
    Oct 16, 2018 at 22:57
  • \$\begingroup\$ @VoteCoffee Field Effect Transistors (FETs) Allow X amps to pass through when Y voltage is applied to their gate (Often termed as "voltage controlled current controllers"). Therefore, by using a FET with its gate biased in the linear working region, the transistor will only allow a set current through, almost regardless of the voltage across its source & drain pins (witin its safe working range, of course). That's what makex this a current-regulated circuit. \$\endgroup\$ Oct 18, 2018 at 16:19

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