Texas Instruments

• Euro line

Model: TI-45 1 version
Battery: BP8 or BP9
Adapter: AC9900
Year: 1977
Chip: TMC1983
Info:At first glance is the European TI-45 identical to the SR-40. Surprisingly the TI-45 features a green vacuum fluorescent display (VFD), a major exception in the Majestic-line. Dismantling this TI-45 manufactured in September 1978 by Texas Instruments in their Rieti, Italy facility reveals a slightly more complex design than the SR-40 sporting a red LED display. Main reason is the higher operating voltage of the VF-Display, engineers at Texas Instruments are using a very effective way to generate -22 Volts out o the 9V battery with a simple voltage multiplier using just four diodes and four capacitors and an charge-pump oscillator integrated on the TMC1980 single-chip calculator circuit. Two variations of the TI-45 were reported, they differ in the mask over the display. View the later model with a molded TI-logo and TEXAS INSTRUMENTS nameplate. 

 On the side you can see the serial, the date of construction 53 week of 1977 and the nation of manufacture Italy.

• Euro line

Model: TI-45 2v
Battery: BP8 or BP9
Adapter: AC9900
Year: 1978
Chip: TMC1983
Info: The TI-45 uses the exact same 4 ceramic capacitors plus 4 diodes to boost the 30 V anode voltage. No other components beside the TMC chip

• Desktop line

Model: TI-450
Battery: 
Adapter: 120 vac
Year: 1974
Chip: TMS0203, TMC0322
Info:

• First lcd and Slimline lcd

Model: TI-50
Battery: 2 x LR44
Adapter: 
Year: 1979
Chip:  TPO321
Info:  first LCD and slimline LCD   

• Desktop line

Model: TI-500
Battery: 
Adapter: 120 vac
Year: 1974
Chip:TMS0203, TMS0221, TMC0305
Info: This rare TI-500 was introduced in the year 1974 and seems to be a sibling of the TI-450 and TI-620.The TI-500 is based on the TMS0200 Chipset for 12-digit desktop calculators but misses the usual 12-digit display. Related calculators using this chip set are the SR-20 and SR-22. The first usage of the TMS0200 Building Blocks were the TI-4000 and the Canon 121F. The architecture found in this TI-500 differs greatly from these calculators, it uses the  Data Chip TMS0203, ROM Chip TMC0305, adding the Printer Chip TMS0221 to control the drum printer.