The core of this project is a PIC12F1501 and CAT4101 led driver. The CAT4101 is the LED constant current driver and takes care of controlling and driving the LED. The PIC12F1501 is used to control the dimming via PWM, Fan control (either PWM or just on / off), and tracking the user input via the buttons. One button increases the brightness from off though 10 levels ending in full brightness while the other decreases the level. Pressing both buttons at once will skip from off to full on or if already on to off.
Other than this card just a power supply and a LED (or string of LEDs) are required to complete this setup. When choosing the LED (or string of LEDs) keep the following in mind. The maximum supply voltage for the CAT4101 is 25V and requires 0.5V drop for the regulator. So the maximum LED (or string of LEDs) voltage can be is 24.5V. When choosing the power supply it must be greater than your max LED (or string of LEDs) voltage, less than 25V, and less than your LED (or string of LEDs) on voltage plus 6V.