hi, This is a bit of a noobish problem but I've about half finished my first proper arduino based gadget and I want to make sure I don't burn anything out. I'm trying to drive an array of LEDs from an ATMEGA328P, 1 bank of white lights that can be used as a flashlight or emergency beacon, and 1 bank of IR transmitters for using the IRremote library. (It's a bit of a multitool).
The problem is I'm not sure how best to drive them, as each LED draws 100mA, making 300mA per bank. I was planning on using a BC517 transistor on each pin, as shown here:
This circuit seems incomplete, and I don't know if the BC517 is fast enough for IR communication. It seems like there would need to be a pull-down resistor between each base pin and ground, is that needed? What about a series resistor between the arduino pin and the base pin? Any help or advice would be much appreciated, I've been reading bits and pieces of theory but it just feels like I need to get a foothold on this.