Texas Instruments IC - Integrated Circuits

Texas Instruments invented the integrated circuit (IC) in the year 1958. The first calculators with integrated circuits used DTL (Diode Transistor Logic), RTL (Resistor Transistor Logic) or TTL (Transistor Transistor Logic) elements. These IC's are small building blocks with typical 4 logic gates or 2 flip-flops in a 14 to 16 pin plastic housing. To get a working calculator you need more than 50 of them. The Cal-Tech project demonstrated in 1967 a calculator using only 3 LSI circuits (Large Scale Integration) with more than 1000 transistors per circuit. From that starting point the calculator race created every year new integrated circuits with higher complexity following the Law of Moore. Working at another supplier of integrated circuits, the well known company Intel, Moore stated: Every three years the complexity of integrated circuits will double. The law is proofen, within 30 years the complexity reached more than a million of transistors per integrated circuit. 

In the meantime Texas Instruments stopped the production of integrated circuits for calculators. Most modern TI products use chips from Toshiba. View the calculator chips manufactured by Toshiba here.

It's difficult to get information about the calculator circuits manufactured by Texas Instruments. The following table gives an overview of the known circuits, a brief description and the calculators using them. 

First TI chip set produced for Canon Inc.

This set of 3 integrated circuits was streamlined to the Pocketronic with it's thermal printer. 
These chips are manufactured in a "state of the art" 10-micron 1-metal PMOS process and using Dual-Inline-Ceramic or Plastic (DIC/DIP) cases with 40 pins.

Second TI chip set produced for Canon Inc.

The second chip set supported displays instead the thermal printer of the Pocketronic. Two different Data Chips are known, the Arithmetic Chip was later replaced.
These chips are manufactured in a "state of the art" 10-micron 1-metal PMOS process and using Dual-Inline-Ceramic or Plastic (DIC/DIP) cases with 40 pins and 28 pins.

Third TI chip set produced for Canon Inc.

This chip set consists of 6 integrated circuit, one of them was later replaced.
These chips are manufactured in a "state of the art" 10-micron 1-metal PMOS process and using Dual-Inline-Plastic (DIP) cases with 40 pins.

Forth TI chip set produced for Canon Inc.

Compared with the previous chip sets the trend goes toward single chip solutions. Both chips contain together 512*13-bit read-only program memory, a 19*16-bit random-access memory and support calculators with upto 14 digits display width.
These chips are manufactured in a "state of the art" 10-micron 1-metal PMOS process and using Dual-Inline- Plastic (DIP) cases with 40 pins.

First TI chip set produced for Sumlock-Compucorp

This huge chip set was developed by the engineers of Compucorp and produced by AMI. Later TI qualified as a second source to AMI. The chip set forms one of the first programmable calculators, the Compucorp 324G Scientist.

First TI chip set produced for Olivetti

This rare chip set was found recently in a Olivetti 55 desktop printing calculator. The keyboard of the calculator sports additional [00][000] keys, unusual [*=] [/=] keys and a memory.
These chips are manufactured in a "state of the art" 10-micron 1-metal PMOS process and using Dual-Inline- Plastic (DIP) cases with 28 pins (TMC1876) and 16 pins (TMC1828, TMC1877).

First commercial available single chip calculator

The first commercial available "calculator-on-a-chip" was an MOS integrated circuit announced by TI in September 17, 1971. Get the original press release here. The chip containes 3520-bit read-only program memory, a 182-bit random-access memory and a decimal arithmetic logic unit as well as control, timing, and output decoders but no drivers for the display. This gives an overall complexity of roughly 5000 transistors. The typical supply voltage ot this chip is ±7.2 V at roughly 15 mA power consumption. 
These chips are manufactured in a "state of the art" 10-micron 1-metal PMOS process and using Dual-Inline- Plastic (DIP) cases with 28 pins.
It took about a year till the first copy of the original design appeared. US based company MOSTEK introduced the MK5020P December, 1972.

First commercial available single chip scientific calculator

The original single chip calculator was limited to basic calculators. The TMS0120 added to the 8 digit mantissa a two digit exponent display but still uses external display drivers.  

Later single chip calculators

There are some later single chip calculators using external drivers for the display. One calculator, the Exactra 20 used only digit drivers, the segment drivers of the calculators were connected directly to the display. The TMS0135 e.g. containes 8192-bit read-only program memory, a 256-bit random-access memory and a decimal arithmetic logic unit as well as control, timing, and output decoders and the segment drivers for the display. This gives an overall complexity of roughly 8800 transistors. 

Chip set for 12 digit calculators

One limitation of the 28-pin packages of the TMS01xx was the maximum number of 10 or 8+2 digits for the results. For desktop calculators Texas Instruments developed chip sets with two 40-pin integrated circuits.    

Chip set for scientifical calculators

With the TMC0501 building blocks Texas Instruments created a novel architecture for scalable scientific calculators. The architecture used minimum a 2 chip design with the Arithmetic chip and the SCOM (scanning read only memory) but was expandable to a maximum of 8 SCOM's, additional RAM as program memory for programmable calculators, additional RAM for general purpose registers and even a chip driving a printer. Most scientific and programmable calculators from Texas Instruments between the years 1974 and 1982 (SR-50..TI-59) use these chips.
 
Abbreviations:

Texas Instruments used the leading designation TMS (Texas Mos Standard) or TMC (Texas Mos Custom) for most chips. The following table uses only the (more common) TMC designations.