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What is a TTl Integrated Circuit and what is it used for? Answered

I got 3 TTl Integrated Circuits but I don't know what they are or what they are used for. So I was wondering if any one can help me, I would really appreciate that.The text on the bottom of them is 17T4 and the text on the top is 402198K  SN7400N .


I go to these sights for data on ICs, transistors, and diodes.
This is my favorite sight to get data sheets.

When you look up ICs the number you want starts with, SN, HD, MC, DM, LM some will have just 7404 instead of SN74LS04 or 14066 instead of MC14066.

I have an alphanumerical list of ICs as well as a transistor code list.

Some Transistors will be marked 3906 instead of 2N3906.
If the number on the component is 9013, you may half to try several abbreviations like 2SC or 2SK, and look at the data sheet to make sure the component looks like the one in the data sheet.

If you private message me and I can send the lists in MSWord.

Its a standard Quad 2-Input NAND gate. It is the most popular type of logic gate. All other forms of logic can be designed using the NAND gate. Here are some examples. Inverter (two NAND inputs tied together) AND (a NAND followed by an inverter) OR (two inverters feeding the inputs of a NAND) NOR (an OR feeding an inverter) and so on. Want to learn more about electronics? The GuruSantiago can help. Checkout his videos here: http://www.youtube.com/user/ElectronicsIsFun And follow him on twitter @ElectronicsFun

This particular TTL semiconductor is a quad 2 input nand gate. it's karnough map looks like this (A and B are the inputs for a given gate)

0  0  1
0  1  1
1  0  1
1  1  0

The thing to remember with TTL is that they are designed for pretty much exactly 5v operation. they don't tolerate other voltages at all well unlike their CMOS cousins.

They are 74 series logic chips. They hold several copies of fundamental building blocks for circuits, in this case 4, 2 input NAND logic gates. Look up 7400 logic on Google

+1. TTL, by the way, stands for "transistor-transistor logic", which was an improvement over the older RTL designs (resistor-transistor logic).

... and the SN prefix further qualifies the exact kind of circuit used. (SN chips use Shottkey junction and draw less power than their predecessors. There are even lower-power versions now, of course; the SN7400 family is at least 40 years old at this point..)

Agreed. @author: Additional info: The TTL stands for Transistor-Transistor Logic. The other major family of integrated circuits is CMOS. Wikipedia both of these for more information: TTL and CMOS.