DATAMATH CALCULATOR MUSEUM
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DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-25
| Date of introduction: | 1978 | Display technology: | LCD |
| New price: | $27.95 | Display size: | 8 (5 + 2) |
| Size: | 5.2" x 2.9" x 0.4" 133 x 73 x 10 mm3 |
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| Weight: | 2.8 ounces, 80 grams | Serial No: | 40850 |
| Batteries: | 2*LR44 | Date of manufacture: | mth 05 year 1978 |
| AC-Adapter: | Origin of manufacture: | Japan | |
| Precision: | 9 | Integrated circuits: | Toshiba T3763 |
| Memories: | 1 | ||
| Program steps: | Courtesy of: | Joerg Woerner | |
| Download manuals: | 
(US: 6.7 MByte)
(EU: 18.6 MByte) |
With
the TI-25 Texas Instruments entered in 1978 the market of scientific
LCD-calculators. On a first view the TI-25 looks like one of the later slimline
models TI-50 or TI-35 but it
is totally different. This calculator was
produced in Japan in opposite to the later US origin of the slimline models and
is somewhat larger.
The electronics of the TI-25 is based on a Toshiba design
with only 9 digits of calculating precision instead of the later US designs with
11 digits precision. Comparing
the TI-25 with the Toshiba SLC-8260
gives the impression that the whole calculator is is a Toshiba design.
The first version of the TI-25 was soon replaced with a design using the PN1033734 calculator chip. Find more information here. Don't miss a rare TI-25 with a yellow polarizer for the liquid crystal display.
Don't miss the Toshiba SLC-8300, the first scientific calculator using a yellow LCD.
If we trace back the routes of Toshiba calculator chips within the TI-line, we evaluate:
| Type | Model | Introduction | First Toshiba IC |
| Basic | TI-1750 (1st) | year 1977 | T3532, year 1976 |
| Basic SLR | TI-1766 | year 1981 | T6789, year 1981 |
| Scientific | TI-25 | year 1978 | T3636, year 1977 |
| Scientific SLR | TI-30 SLR | year 1982 | T6824, year 1982 |
| Financial | none | T6787, year 1982 | |
| Financial SLR | BA-SOLAR | year 1986 | T7917, year 1986 |
It took only a short time between the introduction of a
Toshiba calculator chip and the corresponding Texas Instruments calculators. For
the financial calculators TI used between the years 1978 and 1986 always their
own chips, the missing link could be found with the Canon
Financial calculator.
It was not unusual for Texas Instruments to start an epoche with Japanese technology and move later to US developments. You'll find similar approachs from the TI-1750 to the TI-1030.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, December 5, 2001. No reprints without written permission.