Cin is the Carry Input, because there is no Carry input connected, so that pin must connecting to GND, if that pin is floating, it could be affect the S(Sum).I connect all the ics to power and ground, but when I flick a switch, it shows both LEDs flashing. What do you mean by connect cin to ground?
Don't forget, if you're using switches or something for the inputs, you'll still need to use a pull-down resistor. That is, use a fairly high-value resistor to connect the inputs to ground. That way, when you press a button and connect that pin to power, you're not shorting to ground, and the IC still sees the high voltage, yet when the button isn't pressed, the input isn't just "floating". Floating inputs will act crazy due to static and other interference. For example, ff you use a counter, and leave the CLOCK input floating (or, better yet, connected to a wire you're holding. Like an antenna), you'll actually be able to see it begin to count; Usually at around 60 Hz, due to mains interference.I also didn't ground the unused inputs of the ics, that may be a problem too. I will try again.
I'm not sure what you mean by "vibration"?The 2nd Xor and first AND gate had a common input pin - Cin, so grouned it if you unused.
>I also didn't ground the unused inputs of the ics, that may be a problem too. I will try again.
The first bad thing is increase the current dissipation.
The second bad thing is when the floating pins occur the vibration, the vibration could be affect the others input gates of CMOS IC.
You can do it with two of the gates from a quad XOR gate and three of the gates from a quad NAND gate.Hey guys,
I am trying to make a full adder with these ics:
(2) 4011 Quad Nand Gate
(2) 4001 Quad Nor Gate
(1) 4070 Quad Xor Gate
(1) 4049 Hex Inverter
Can it be done?
I'm uploading on the OPs behalfOk, I did that and 1 LED was on, the Cout LED. I made a diagram of what my circuit looks like but I can't put it on this. Here is my email if you want the image: aj8898@aol.com If not, thanks for helping, I will try more.
I believe you can't upload with less than 10 posts on the forum.>I made a diagram of what my circuit looks like but I can't put it on this.
You have to use the reply function, if you wish to upload any images.
And then you will find the function located on lower of the messages box, as:
Additional Options
Manage Attachments ← choose this key to get your images that you want to upload.
When you upload the images successful, then you just move the cursor to the image linked line, and then click right key to active the menu, and choose the function as duplicate the linked website.
And now you can put the image on your messages box where you want to paste it.
Choose the function - insert image, the function located on upper of the messages box(there is a mountain on it), and paste the image linked page that you already copied.
And move the cursor to choose the place where you want to paste it.
Thank you, you are right, many forums had that kinds of rule.I believe you can't upload with less than 10 posts on the forum.
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