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I have a short question.
I have to read this text regarding the 555 IC:
As you can see, there is the following sentence:
"Even at 5V, the 555 will easily drive LED's and small relays."
Can someone explain to me what exactly does this mean? Like...
Why is is true?
Why is it important?
Thank you!
You need to consider this in context of the full statement
The output is fairly powerful, especially when the supply voltage is 15V, and will supply up to 200 mA. Even at 5V, the 555 will easily drive LED's and small relays.
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Why is this true?
The output transistors of the 555 have a relatively large current handling capability. 200mA output at 5V is a full Watt, while at 15V, that is 3W. That's a good bit of output, compared to a microcontroller.
Why is this important?
If you want to drive LEDs or relays directly, this tells you that the 555 is capable of driving moderate loads without external components or external buffers. This is useful if you want to keep your parts count low or would rather not deal with a buffer stage.
It's saying that even at that lower voltage, the 555 can still drive significant loads. Some chips wont be able to directly drive those things, and will need some sort of amplifier.
It is true because in the output stage of the NE555 chip (connected to the flip flop) there is a buffer that can sink "high" currents, usually some hundreds of mA. So if you have to drive a relay or a LED you don't have to use an external transistor or some others power drivers circuits. It is important to know this thing because in this way you don't need οthers external components in your project.
