Canon LE-10

Date of introduction:  January 1972 Display technology:  LED-modules
New price:  $259 Display size:  10
Size:  5.7" x 3.2" x 1.5"
 146 x 82 x 38 mm3
Weight:  15.5 ounces, 440 grams Serial No:  158965
Batteries:  4*NiCd AA Date of manufacture:  year 1972
AC-Adapter:   Origin of manufacture:  Japan
Precision:  10  Integrated circuits:  TMC1824, TMC1825A
Program steps:   Courtesy of:  Joerg Woerner

LE-10_0.jpg (51767 Byte)When Canon introduced in 1972 the LE-10 it was far ahead competition. The smart housing accommodates not only the calculator chip set of the LE-100A but even a rechargeable battery assembled of 4 AA-sized NiCd batteries. 

LE-10_7.jpg (36803 Byte)A huge cradle holds the calculator during recharge-time of the internal batteries. The small analogue battery meter gives you the remaining operation time of the LE-10.

Dismantling this Canon LE-10 calculator manufactured in 1972 reveals a genius masterpiece of Japan's engineering capabilities. The internal construction of the LE-10 is based on a robust chassis holding three printed circuit boards (PCBs) - two of them easily removable for repairs:

Main PCB with hybrid display drivers and power supply.

Calculator brain with the Texas Instruments TMS1824 and TMS1825 chipset known from the Canon LE-100A.

The Canon LE-10 followed the Pocketronic and uses red LED-modules manufactured by Texas Instruments to display the 10-digit results instead the serial thermal printer.

The overall power consumption of the LE-10 dropped dramatically and the combined 13 rechargeable NiCd cells were replaced by s small module with just 4 cells.

In Texas Instrument's history of Integrated Circuits for calculators the LE-10 plays an important role. If you remember the three LSI-circuits of the Pocketronic, you will find in the LE-10 only two chips of a later generation but one step towards the single-chip calculator chip. 

TMC1824 - Data Chip
TMC1825A - ROM Chip

The same chip set was used in the desktop calculator L100A introduced in the year 1971.

A special feature of the LE-10 is the 10-digit display compared with the the successor LE-80 making use of the TMS0101 "calculator-on-a-chip" driving only an 8-digit display. It took some time before with the LE-100 again a 10-digit calculator in the Canon’s pocket calculator line appeared. In the meantime some odd calculators like LE-80M, LE-80R, LE-81 and LE-82 were introduced before the LE-83, LE-84 and LE-85 settled the design line.  

According to Shinichiro Osaki a later model carried the designation LE-10A. Differences are unknown but could be found in a LED display manufactured by Antex and provided by Amcon, Canon's subsidiary situated in Silicon Valley, California.

In 1974 the era of pocket calculators with LED displays was over in Japan and Canon introduced with the LD-80 their first product with the green VF-Display (Vacuum Fluorescent). Main advantage of this technology was that time both lower power consumption and cheaper purchase price. Interesting to know that Texas Instruments – manufacturing their own LED displays – introduced only few VFD calculators.

Don't miss competition, the Sharp EL-811 and the later Toshiba BC-1205B sporting a 12-digit display.

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