Hello, I am relatively new to using transistors in my circuits and need some help understanding the scenarios they are used for. I want to make an Arduino 7-segment digital clock out of LEDs in parallel that switch on/off and are controlled by 8-bit shift registers. I have read in posts that switching on/off multiple LEDs in parallel could burn up a 555 chip if powering the LED's directly off the chip, and that transistors help resolve this.
I think I generally understand how transistors work by switching larger currents, I just don't understand in what cases to use them and why they are useful here. Like how would I know that a 555 chip would burn up in this case if I tried using it alone?
Thanks and please point out if I'm misunderstanding anything!
EDIT: Ok, I didn't realize that chips in general have a supply voltage range/limit and can't supply more than that. If I'm correct, this means that multiple LEDS in parallel require more power than the chip can provide, thus a transistor is needed?