Standard Logic History

At the moment other advances in semiconductors are taking a backseat when compared to the AI boom. They're still happening, and not all about adding the next few billion transistors.

As a young engineer everyone's desk had 'The TTL (Transistor-Transistor Logic) Data Book for Design Engineers'. Details of the complete families of standard logic ICs. It was the way most electronic products were designed.
To be honest, I thought they might have disappeared. But they're still here, and in tiny packages - some as small as 0.6mm. For example it can make sense when you design an ASIC, spend a fortune on masks, it doesn't quite work, but a few tiny standard logic ICs can be added externally instead.

It was Fairchild's introduction of the integrated circuit and its 900 series RTL (Resistor-Transistor Logic) in 1961 that completely revolutionised electronics. Interestingly around the same time, IBM were developing an equivalent for its revolutionary System/360 that were ceramic substrate based devices, with deposited metal, thick film resistors and a few transistors. At the time IBM weren't yet convinced on the reliability of early ICs, and they could trim their in-module resistors, improving RTL logic function performance.

 

Fairchild uL903 IC

 
The Fairchild IC image is magnified detail from a uL903 3-input NOR RTL integrated circuit showing two of the three transistors in the circuit. The collector contact is at the top of the picture with the emitter then base contacts underneath. This was one of the first ICs, and the sole logic function used for the Apollo Guidance Computer.
 
 
IBM Mainframe Circuit Card
 
The IBM circuit card is a later version of the Standard Modular System (SMS) that IBM created for the System/360. The SLT module format remained beyond the simple logic function. The image also has an early SLT module in the background without the metal lid.
 
The major downside of RTL was the very high power dissipation of its on-chip resistors. In 1962, Signetics a spin out from Fairchild introduced the SE-1000 series, the first major DTL (Diode-Transistor Logic) family of ICs.
 

A Signetics74LS161 4-bit Counter from 1981

In 1963, Sylvania introduced the first family of the further improved and faster TTL (Transistor-Transistor Logic), called SUHL (Sylvania Universal High Level Logic). Very quickly, Texas Instruments and others introduced their own families of standard logic functions. Initially TI gave the logic family the prefix 54, then the 74 series with a narrower operating temperature range.

Fairchild, Signetics and other semiconductor companies eventually followed the lead of TI, and the ordering system for bipolar TTL.


Nexperia Standard Logic Packages


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