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Use independent opamps for each string instead of a current mirror, might have extra voltage but the current level should be good. More effective, less efficient, other considerations include needing a FET in a power package and that the switching frequency will be lower
We could add balsast resistors though this is probably not needed since we are using the current mirrors
Sounds expensive but using a mag-amp with one dc driver for dimmable leds
Increase the FOV of the lights
increase power efficiency
Vary threshold voltages (use low voltage thresholds)
stack transistors in series
if we are using linear regulators switch to switching regulators
we can use fast switching mosfets
add more thermal vias if possible.
Make sure we keep the ground and power planes for low impedance paths
Adding decoupling and bypass capacitors (for filtering) near power pins of components
Center high power components for better thermal efficiency
even thought the driver boards are small, try to keep things away from the edge of the board
if necessary add heat sinks
Test the current boards with a PDN analyzer?
Probable Upgrades
Add reverse polarity protection using PMOS transistor
Example Circuits
https://youtu.be/oFdsiRMZZWk?t=145
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