I am a sophmore at an university. I am taking digital logic and intro to computer hardware class, and I need help with a lab. I am supposed to find a simple design for a debounced switch that can be built using the materials in our lab (as far as I know, we don't have any resistors). However, I cannot find a simple design for one. All we have to work with are some standard TTL chips (7400, 7402, 7403 just to name a few). It also doesn't help that the teacher hasn't talked about these in the lecture part of the class, so I'm not entirely sure what a debouced switch really is (I did some internet research and have the basic idea though). Can someone help me find a design for a simple debounced switch? I think I found one, but it mentions that I need some resistors (found here: http://www.ee.nmt.edu/~elosery/fall_2009/ee231L/lab6.pdf, p. 3 figure 2). Would I really need the resistors and is it really a debounced switch?

 

I know we have JK Flip Flop chips and D Flip Flop chips, but I don't know about any other Flip Flop chips

 

Have I got a reference for you!

Read here: http://www.ganssle.com/debouncing.htm

You will find it very educational and helpful.

 

 

I am a sophmore at an university. I am taking digital logic and intro to computer hardware class, and I need help with a lab. I am supposed to find a simple design for a debounced switch that can be built using the materials in our lab (as far as I know, we don't have any resistors). However, I cannot find a simple design for one. All we have to work with are some standard TTL chips (7400, 7402, 7403 just to name a few). It also doesn't help that the teacher hasn't talked about these in the lecture part of the class, so I'm not entirely sure what a debouced switch really is (I did some internet research and have the basic idea though). Can someone help me find a design for a simple debounced switch? I think I found one, but it mentions that I need some resistors (found here: http://www.ee.nmt.edu/~elosery/fall_2009/ee231L/lab6.pdf, p. 3 figure 2). Would I really need the resistors and is it really a debounced switch?

Hi EonsNearby,

For the circuit in the lab you posted, and for the other one presented (I guess some people do not read well), yes, you would need resistors.

In any case, do you have access to a single pole, double throw (SPDT) switch, like the one in the lab schematic?

 

With no capacitors, and the fact you are given a SPDT switch, it appears you are to build the S-R latch on page 3 of the attachment.

--ETA: Reading the first page:

In this lab we will use the logic analyzer to look at switch bounce, and use an SR latch to debounce a mechanical switch.

---ETA Again.... Clock a few FF's together from the input signal, and when they all match, output that value.