# Hello! New to circuits

Discussion in 'The Projects Forum' started by zyphirr, Feb 14, 2009.

1. ### zyphirr Thread Starter New Member

Feb 14, 2009
4
0
Hi, my name is Tim. I'm a sophomore in Computer Engineering and Computer Science. I'm constructing my first electronic circuit, sorta, and I ran into a wall.

I have to build some simple logic circuits on a solderless breadboard using some 74xx integrated circuits (IC), an inverter, a DIP switch, and some LEDs. They supply me with the circuit diagram, but I don't really understand where to wire the inputs and outputs of the circuit. The individual numbers correspond to the IC's.

1) Do I wire the number of the IC's directly into the DIP switch?

2) Where do the outputs go to?

I'm very green when it comes to circuits, so please don't be too technical when you try to help me, thanks much in advance!

2. ### beenthere Retired Moderator

Apr 20, 2004
15,815
282
It might help with the confusion if you get the data sheet for a 7410. The IC package has a marker on the top to help with orientation, and pin 1 is always the top left pin. Pin numbers wrap around the bottom, so pin 14 will always the at the top right (or 16, or 24, as the case may be).

The partial schematic you posted does nothing of itself. The U1 gates can only go low at the output is all the inputs are logic highs (each gate is an NAND). U2A is a negative OR. going high if any input is low.

Does your instructor really expect you to just pick up some logic gates and do something with no background? If that is the case, you need to find some material
you can read beside the data sheets for the 7410's. Pay attention to the limits for Vcc and always tie unusued inputs either to ground or pull them up with a 4.7K resistor.

You can always think of using the logic to illustrate some simple Boolean equations - one nice thing about NAND gates is that they can be used for any function possible.

3. ### zyphirr Thread Starter New Member

Feb 14, 2009
4
0
I think it's just me who lacks the necessary background.

I understand boolean algebra and all the stuff on paper, but when it comes to these physical circuits, I'm lost. I know I can pick up on this fairly quick if I could just get a tutorial. Being in a class of roughly 150 students, my instructor and 2 other TA's are the people who I should go to for this tutorial.

I was just thinking that I should get into a forums where I can get additional help (when I can't get help from anyone else in person).

Anyways, thanks for trying!

Apr 20, 2004
15,815
282