Logic IC Numbering

- details of the part numbering systems used for logic IC numbers including 7400 series, etc.

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Logic IC families & Technologies Includes:
IC logic families & technolgies summary chart Numbering schemes 7400 Series TTL 7400 sub-families listing

The part number for most logic ICs gives a lot of information about its function, performance and manufacturer.

It is possible to tell the logic family, the manufacturer and various other elements of the performance of the logic IC simply by looking at the number and deciphering the code.

There are several different types of numbering system, dependent upon the overall logic family in question.

7400 series IC numbering

The most widely used logic family is the 7400 series, i.e. 74xx00 series and all its derivatives. The derivation of these IC numbers is given below:

Numbering scheme for the 7400 or 74xx00 series logic family showing manufacturer, temperature range, logic family, device type and package

It can be seen that this IC part number consists of a number of elements:

Part Numbering Scheme for 74xx00 Series Logic ICs
	Manufacturer		This code normally consists of two letters and is a code normally used by a given manufacturer. SN is one used by Texas Instruments. Other manufacturers have their own codes that they place here.
	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. For most applications the 74 series is perfectly acceptable and this series will be found in consumer devices.
	Logic series		This is the sub-family. 7400 for example is the basic series, but there are many others.
	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.

7400 series logic part numbering infographic

In order to summarise and provide more information about the popular 7400 series logic technologies, I've produced a summary infographic.

This provides a visual breakdown of the part number with explanations and examples of the different chips available.

7400 series logic part numbering
*Click on image for larger version*

4000 series IC numbering

The 4000 series was the first family or series of CMOS ICs. They were widely used in their day and although available today, they are not as widely used.

Numbering scheme for the 4000 series logic family showing manufacturer, logic family, device type and package

It can be seen that this part number consists of a number of elements:

Part Numbering Scheme for 4000 Series Logic ICs
	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.