Display used in TI calculators

The official introduction of the TI-2500 Datamath portable calculator and the desktop models TI-3000 and TI-3500 dates back to September 21, 1972. The three calculators used different display technology: The TI-2500 portable electronic calculator a red 8-digit light-emitting-diode (LED) display and the desktop models an orange gas-discharge displays with either 8 or 10-digits marketed by Burroughs as Panaplex™ display. Main disadvantage of these technologies was their high power consumption, later calculators like the TI-1750 used liquid-crystal-displays (LCD). The first LCD used yellow polarisation filters to damp the ultraviolet radiation of the sunlight, later calculators like the TI-25 got transparent filters. One step between the LED and LCD marked the TI-1025 with its green vacuum flourescent display (VFD).

Multi Digit Module LED Display 

This set of 3 integrated circuits was streamlined to the Pocketronic with it's thermal printer. 

Single Digit Module LED Display 

This set of 3 integrated circuits was streamlined to the Pocketronic with it's thermal printer. 

Multi Digit Stick LED Display 

This set of 3 integrated circuits was streamlined to the Pocketronic with it's thermal printer. 

Panaplex™ Display

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.

VFD (Vacuum-Flourescent-Display)

This chip set consists of 6 integrated circuit, one of them was later replaced.

LCD (Liquid-Crystal-Display)

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.

If you have additions to the above article please email: joerg@datamath.org.

© Joerg Woerner, April 13, 2001. No reprints without written permission.