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what does this cd4011be chip do? Answered

on the datasheet it says its a CMOS NAND GATE, what does it do and what do i use it for?
http://pdf1.alldatasheet.com/datasheet-pdf/view/113449/TI/CD4011BE.html  <<Datasheet


It makes a great warble alarm sound effect. Check out the Ramsey Mad Blaster Warbler Alarm. The circuit uses a 4011. www.ramseyelectronics.com/downloads/manuals/MB1.pdf In this PDF it appears that they omitted the schematic for building it. I think I feel a new instructable coming on.

so what do i use it for? or what are the things i could use it for?

and let me see if i got this straight. if there is voltage on both of the input pins, then there is none on the output pin?

yup...like a VERY rudimentary coin acceptor that kicks out slugs that don't fit certain critera. if the coin is not a and b, it gets the kick. "lock the door unless both keys are inserted" is another scenario.

Where it gets interesting is when you CASCADE gates, so that one feeds into another, etc...since this one is a quad gate, it has 8 inputs and 4 outputs. Some of those outputs can feed other inputs to make a more complex system.

Generally they're used for such things as making sure certain circuits are in certain conditions before allowing something else to happen. in a rocket launcher, you would use AND (not NAND) to say 'is the safety turned on, and is the launch buton pressed, then launch the rocket"

ok thank you for dumbing it down for me :) i just pair the output with the common ground, and it outputs a voltage similar to the power supply, right?

The chip itself will have +V and ground to power itself -- all the signals will be in relation to that Vcc and Ground. In that truth table 1 = +5 volts, and 0 = either disconnected, or physically connected to ground (depends on what the datasheet says).

is this about how it works? (and do i use power on the "logic pins" or can i use a switch?


almost. "-5" should be "0 volts", ground.

You can look at it as a difference of +5 between Vcc and Ground. so if ground is -5, that's fine, but then Vcc is zero. Most commonly, ground is 0, and Vcc is Positive (5 in this case).

If you apply 5 volts to both input I and input II, you get 'not and' II (or zero, ground) on the output.

What you have to look for is 'are the inputs high impedence' meaning they look like a REALLY big resistor, and draw virtually no current -- or are they designed to absorb lots of power, and act as a current sink.

ok i get it now. sorry if it seemed like i was wasting your time. thanks :)

Good questions often require more digging. Good on you for being willing to learn.

You need to do some serious study of logic gates before the device is going to be any real use to you at all. Try starting here http://en.wikipedia.org/wiki/Logic_gate