djQUAN
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Datasheet says no, I say yes.. by just adding two components
Based on the AMC driver datasheet, it can only accept voltages of up to 7V max. Running it on 12V will surely blow the IC apart.
I have a use for this: COB LED strip from DX powered off the solar 12V system in my house so I need to run it off 12VDC.
Since running it to its max rated 1320mA produces a great deal of heat, I found from previous LED lamp builds that underdriving these results to minimal reduction of light output but increases its efficiency and less heat to dissipate but still bright enough for my intended uses.
Since its measured Vf is only 11.3V, I decided a low dropout linear driver will work well especially with a 12V supply. A drive current of 700mA is about right from testing.
This is the circuit I made to run an AMC7135 at 12V (expect the actual used two AMC drivers in parallel for 700mA).
The IC will be dropping only about 1V from a 12V supply so heat should be minimal.
Parts used: AMC7135 and LED star with inbuilt AMC driver from FT, COB LED from DX
I mounted the AMC chips on the LED star as it was convenient (rather than etching my own PCB) and acts a good heatsink for the chips since it's an alu core PCB. I didn't have a 5V zener on hand so I used two green LEDs in series for a Vf of about 4V for the AMC chips.
Here's a test setup mounted on an aluminum angle bar.
At 12V, we get a little over 700mA.
Highest I've tested is at 14V though it will never go that high in my application since the battery voltage drops at night (no solar power). Keep in mind the AMC chips are dropping about 5V at that input voltage so it is not recommended unless heavily heatsinked.
Here's the final version. The capacitor is 2.2uF 25V. It is necessary as the wiring inductance triggers the protection circuit of the AMC chip and prevents it from working properly. I also made a 350mA version for dad's room as he uses it for a night light.
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