The actual driver is that UA7805 IC. The tiny IC is a PWM wave generator only (for switching purposes). Using PWM controller to power up LEDs is a good idea - since efficiency is superb. But, take care of the temperature of that UA7805. Any semiconductor leg will need to be operational at below 90 deg C (im guessing that is the burn point of the PCB - rough guess). And the junction temperature of the internal, well, usually should be aimed to be less than 150 deg C. As for me, when in doubt, slap a heatsink on it, and you're good to go lol...
On a second note, that UA7805 is already heatsinked to the silver track of the pcb. Probably it is enough.. not sure. just follow the circuit rating, you should be ok with it.