Toshiba LC-831W

Date of introduction:  1978 Display technology:  2 LCD (yellow)
New price:   Display size:  8
Size:  5.3" x 2.7" x 0.405"
 135 x 68 x 10 mm3
Weight:  3.0 ounces, 86 grams Serial No:  047040
Batteries:  3*LR44  Date of manufacture:  
AC-Adapter:   Origin of manufacture:  Japan
Precision:  8 Integrated circuits:  NEC uPD877G, ?
Memories:  1    
Program steps:   Courtesy of:  Joerg Woerner

Tokyo Shibaura Electric Co., Ltd., better known as Toshiba - the official name since 1978 - introduced early in their history this combination of a calculator and clock. This LC-831W combines a standard calculator like the LC-830 with an additional watch module. Please notice the grey color of the clock display and the extra LIGHT-button. 

LC-831W_PCB.jpg (57328 Byte)Dismantling the LC-831W reveals indeed a printed circuit board (PCB) with two different integrated circuits. The bigger one - a NEC uPD877G - includes the complete calculator functions, the smaller one - unfortunately without designation - is connected only to the small clock display, an quartz oscillator and some small components.

Don't miss the Olympia HIT 2000, introduced a few month before this LC-831W. Later products like the LC-833WA combined the calculator and clock into only one integrated circuit driving a common LC-Display.

If you are curious about the first calculator-clock combos you should visit three products introduced already in 1972 and 1973: Garrett 2002, Corvus 305, and Texas Instruments TI-3510.

If you have additions to the above article please email:

Joerg Woerner, February 27, 2004. No reprints without written permission.