Best way to boost 6v to 9v (variable) at highish currents?

[revilo951]

Hello,

I have a 6v 10A Power Supply that I want to use to run some high power LED's (overdriven). They are MT-G2's so the nominal voltage is 6v, and I would like to drive them up to 8.5v when I need extra brightness. At 8.4v, they take about 2.5A each.

Can anyone point me in the right direction?

Any more information you need, just let me know!

Thanks!

[sacherjj]

Do a search for LED driver chips  There are many out there for LED backlights and for camera "flash" LEDs.  They are usually done as a current control, rather than voltage control.  Then the boost circuitry take the voltage up to where is needed to provide the current set.

[Teledog]

eBay has buck-boost boards for dirt cheap, do a search. ( Step up /step down power supply)
It's not worth making them yourself.
I buy shitloads ;-)
PS: might want to stick with the same voltage, just slowly increment the current (with suitable heat-sinks)

[revilo951]

OK, I was hoping there would be something that would be a nice project for me to DIY.

I'm not a stranger to eBay.  If anyone has any suggestions for one in the right voltage range that will do 90W+, I'll be glad to hear.

Also, regards:
 

PS: might want to stick with the same voltage, just slowly increment the current (with suitable heat-sinks)

Do you care to explain a little? ('scuse my noob question here) Doesn't ohms law come into play? Or do you mean just adjust the current and let the voltage look after itself (adjusting the current rather than the voltage)? From your comment, if I didn't know better, I'd be asking how to increase the current using a heatsink! 

[Psi]

Trying to boost convert 90W from 6V will result in terrible efficiency. Its bad enough at 12V


You'll probably lose half a volt just in the wiring. which is 0.5 * 15A = 7.5W.
And that's before the switchmode conversion has even started.

[mzzj]

Trying to boost convert 90W from 6V will result in terrible efficiency. Its bad enough at 12V


You'll probably lose half a volt just in the wiring. which is 0.5 * 15A = 7.5W.
And that's before the switchmode conversion has even started.

Better than 90% effiency is possible but it wont be easy like slapping wires to cheap ebay module.

[revilo951]

Efficiency is not a major concern here... 

I have a power supply that I would like to use, and will work to do what I want at lower efficiencies, even down to 70%