I have a IKEA RGB Dioder set where each channel requires 12Vdc (& 1.25W), I want to connect this to my Phidget LED 64 Advanced.
Each channel on the Phidget can provide a maximum of 5Vdc with 80mA, from what I understand I need a resistor in the series to connect three 3 channels to provide sufficient voltage for one LED panel? What type of resistor will I need?
EDIT: I'm currently using what @clabacchio suggested where 7.5Vdc is provided by one transformer and the Phidget bumps up the rest. Only the Red LED cannot achieve perfect on/off switching but I should be able to mitigate this via stepping down all Red LEDs