My LED panel came with a driver that gets really hot, i've measured 95C on the transformer - I dont want to put that driver in my ceiling.
I know that LEDs need constant current, and the driver regulates the voltage.
My driver specs are: 24-45V 300mA
Can I replace this driver with any driver/transformer which has a constant current output on 300mA ? ...just as long as the voltage is between 24-45V?

in short: how do I keep my LED panel, but replace the crappy led driver with a more reliable one?

 

http://www.trcelectronics.com/View/Roal/RCL015-0300A.shtml

 

I agree. It's easier and safer to replace a bad design with something of good quality than to try to fake it by maybe bolting on a heat radiator.

 

Would a driver only output the current a LED request?
e.g.
If a driver is rated at 400mA, would it try to force the output to 400mA, or would it let the LED decide?
and
I assume a higher voltage on the driver output side than specified on the LED would damage it.

 

Would a driver only output the current a LED request?

No. The LED is a current operated device so it will take whatever current you give it until it blows.
It makes no request.
You need a current driver provides the desired current and that can output the necessary voltage to the LEDs.

 

With most circuits, you apply the right voltage and they take the current they need. LEDs are backwards. You give them the current they need and they determine how much voltage is required.

Read this:
http://forum.allaboutcircuits.com/threads/ohms-law-for-noobies-or-the-amp-hour-fallacy.69757/