Texas Instruments TI-1680

Date of introduction:  1977 Display technology:  Fluorescent
New price:  $29.95, 22.95 Display size:  8
Size:  4.9" x 2.8" x 0.65"
 125 x 70 x 16 mm3
Weight:  4.0 ounces, 112 grams Serial No:  997340
Batteries:  Custom made  Date of manufacture:  wk 07 year 1978
AC-Adapter:  AC9132, AC9131  Origin of manufacture:  USA (MTA)
Precision:   Integrated circuits:  TMC1981, TMC0999
Memories:  1 + 20 Playback    
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (US: 7.3M Bytes)

The TI-1600, TI-1650 and the TI-1680 were very flat calculators compared to the previous TI-1200 models. Only one year in front of the first pocket-sized LCD-calculators you could carry them in your shirt.

With this tiny calculator Texas Instruments introduced a new calculator feature, the Playback or replay mode. Similar to a paper printout you can scroll back up to 20 of your entries and do some corrections. This technology was used in the TI-2550-IV, too.

Read more about the memory operations possible with just the [M] and [MR] keys here.

Instead of the normal 9V battery used in other calculators a very flat (custom made by French company SAFT) rechargeable battery is used. The first TI-1680 were sold with the AC9232 charger, later the manual was corrected and the AC9131 delivered.

Sales figures kept very low, soon after the introduction of the TI-1680 the first LCD-calculators appeared on the market.

According to Texas Instruments only between 10,000 and 20,000 units were manufactured.

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Joerg Woerner, December 5, 2001. No reprints without written permission.