Canb i convert 24v 250Mah to 12v500Mah? by resistor

Thread Starter


Joined Oct 22, 2020
hellow. this is my first post. sorry about the english..
be gentel with me :) haha

i have 2 led drivers.
one led driver 12V 500mah - work just fine.
the second led driver is 24v 250 mah

i want to make the 24v to be 12v.
i put 500 ohm resistor in sireus and it work fine - but the resistor was very very hot !!!
can i put more resistors (in other ways) to Cause the heat to divide between the resistors?

thank you alot.


Joined Sep 17, 2013
Welcome to AAC!
You can use series or parallel resistors of appropriate value (e.g. two 250 Ohm in series, or two 1k Ohm in parallel) to share a heat load, or simply use a single resistor of higher wattage rating and a suitable heatsink to cool things down, but for a given load the heat that needs to be dissipated in total will be the same.
You're never going to get 12V 500mA out of a 24V 250mA rated supply, although you could come close by using a high efficiency switch-mode buck converter.
Edit: BTW, supplies are rated in mA, not mAh. (mAh are units of charge, e.g. indicators of battery capacity.)
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