I was given this circuit and it was supposed to be an LED dimmer circuit that changes its brightness (gradually) when the switch is closed/open. I was told that the darlington pair was supposed to "smooth-out" the changing brightness of the LEDs. But here are my questions about the circuit: 1)Why the need for the darlington pair? Cant one transistor do the job? 2)Regardless of the transistor, wont the LEDs come on any way? I mean the way I see it the anode is currently more positive than the cathode - shouldnt this cause the LEDs to light up wihtout any variations in brightness? 3)But the thing that bothers me the most, is the need for the transistors. How exactly is it suppose to smooth the brightness of the LEDs. Is it the collector voltage vs the collector current graph that illustrates this? http://img222.imageshack.us/img222/2923/slowledzi2.png [Broken] --thank you.