Logic IC Numbering
- details of the part numbering systems used for logic IC numbers including 7400 series, etc.
IN THIS SECTION
Logic IC families overview
Logic IC numbering
It is possible to tell much about an integrated circuit from its part number.
Logic IC numbering schemes are no different and dependent upon the type of logic IC and its family, it is possible to tell much about its function and specification from the IC number.
Although there are several very different forms of logic family, it is often possible to gain a good understanding of a particular logic chip from their part numbers. As logic chips are produced by many manufacturer's, industry standards have grown up, enabling manufacturers to second source components from various suppliers.
There are several different types of numbering system, dependent upon the overall logic family in question.

7400 series IC numbering
The most widely used is the 7400 series and all its derivatives. The derivation of these IC numbers is given below:
 
 
It can be seen that this IC part number consists of a number of elements:
 
Manufacturer
 
This code normally consists of two letters and is a code normally used by a given manufacturer. SM is one used by Texas Instruments.
 
Temperature range
 
This is indicated by these two figures. 74 indicates (0°C to 70°C commercial and 54 military (-55°C to +125°C.
 
Logic series
 
This is the sub-family. 7400 for example is the basic series, but there are many others as defined above.
 
Device
 
This indicates the device function / type. For example devices with 04 are hex inverters, etc. They are the common across all sub-families.
 
Package code
 
This is the package suffix. It is necessary to refer to the manufacturers datasheets as these codes vary between manufacturers.
 

4000 series IC numbering
The most widely used is the 4000 series and all its derivatives. The logic behind these part numbers is given below:
 
 
It can be seen that this part number consists of a number of elements:
 
Manufacturer
 
This code normally consists of two letters and is a code normally used by a given manufacturer. HEF is what used to be Mullard / Phillips.
 
Series
 
This is indicated by these the 4 in the 4000 figure.
 
Device
 
This indicates the device function / type. For example devices the 01, i.e. 4001 is a quad 2-input NOR.
 
Output
 
Early devices did not have any output buffering and were lacking in drive. Later versions were buffered and these chips had the "B" suffix added to the part number.
 

These are some of the major logic IC numbering systems. Others are available for other forms of logic, but these IC numbering schemes are not as widely used.
By Ian Poole
http://www.radio-electronics.com/info/data/semicond/logic-ic-families-technologies/ic-numbering.php