Is the idea here to leave the trimpot on the board in place, then wire a parallel resistor in? Or are you still removing the trimpot?mawyatt wrote:Hello,
I've attached a schematic that uses the MT3608 as an LED "CURRENT MODE" controller. This requires just 2 resistors, one a current sense resistor (Rx) and another to scale the feedback potentiometer resistance to control the maximum allowed LED current (Ry).
The example shows the MT3608 with a BC-135 LED, a 5ohm 4watt resistor for Rx (can be a couple 10ohm 2watt resistors in parallel), and a 16Kohm resistor for Ry. Maximum LED current is limited to specification of 0.9amps, and minimum LED current is 0.12amps, with nominal at 0.6amps.
The idea I really liked about this modification over other modifications is that the wheel on the front of the microscope still controls the output. Would I be losing that feature with your retrofit?