Low cost mini boost driver for 3W LEDs

This little driver can handle input voltages in the range of 3.6 to 24V and boost the voltage to drive a string of 3 watt LEDs at 650mA current.

Maximum output voltage is 42V, and you must have a string of LEDs connected to the driver before you power it up to prevent a possible over voltage condition damaging the driver (this is common on boost drivers).

Output current can be changed by swapping out the feedback resistors (the two resistors at bottom-left in the pic, we'll call them Rfb). Remove one (they are wired in parallel) and the current drops to 325mA, perfect for 1W LEDs. Output current is 0.22/Rfb.

A nice simple driver where you need to drive a string of LEDs with a higher voltage requirement than your power supply.

Note that efficiency is better the closer the LED string voltage and the power supply voltages are. Don't try to drive a string of ten 3W LEDs from a 5V power supply, the driver will get hot and die as the input current will exceed the driver IC's 2A maximum input current capabilities.

Driver board measures just 13mm wide x 28mm long and around 5mm thick. Driver uses the XL6003 driver IC, click here for a datasheet.