I've been confused about something for a while.
So logic gates work by basically controlling how current moves from Vcc to either GND or OUTPUT.
Like for example, a NOT gate with input 0 properly moves the Vcc current through the OUTPUT to power for example a LED.
But, if the input is 1, then it flows into GND....and the LED is off.
But the LED is off and current is still flowing.
The sounds like a huge waste of power to me. It sounds like basically a short circuit to me.
I understand putting a resistor before GND but this resistor always has to be smaller than the OUTPUT resistor otherwise the current will just follow the path of least resistance and go out through the OUTPUT. That basically means that GND (off mode) will always waste more power than the OUTPUT path. That just doesn't seem right....
So what do you do about that?
And another thing I do not get is this:
Are logic gates ever completely on or completely off?
Or does it depend on the type of transistor being used? Like I think bjt's aren't usually completely on or off but mosfets can.
So logic gates work by basically controlling how current moves from Vcc to either GND or OUTPUT.
Like for example, a NOT gate with input 0 properly moves the Vcc current through the OUTPUT to power for example a LED.
But, if the input is 1, then it flows into GND....and the LED is off.
But the LED is off and current is still flowing.
The sounds like a huge waste of power to me. It sounds like basically a short circuit to me.
I understand putting a resistor before GND but this resistor always has to be smaller than the OUTPUT resistor otherwise the current will just follow the path of least resistance and go out through the OUTPUT. That basically means that GND (off mode) will always waste more power than the OUTPUT path. That just doesn't seem right....
So what do you do about that?
And another thing I do not get is this:
Are logic gates ever completely on or completely off?
Or does it depend on the type of transistor being used? Like I think bjt's aren't usually completely on or off but mosfets can.
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