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Texas Instruments TI-2200 II CheckWriter

Date of introduction:  October 1986 Display technology:  LCD
New price:  $19.95 (SRP 1988) Display size:  8
Size:  2.8" x 6.1" x 0.25"
 70 x 154 x 7 mm3
   
Weight:  2.5 ounces, 72 grams Serial No:  
Batteries:  LR54 Date of manufacture:  mth 03 year 1987
AC-Adapter:   Origin of manufacture:  Taiwan (C)
Precision:  8  Integrated circuits:  Toshiba T7752S
Memories:  3    
Program steps:   Courtesy of:  Stefan Klaes
    Download manual:   (US: 4.3 MByte)

National Semiconductor introduced already in 1978 with the NS103 Data Checker an electronic record keeper with three continuous memories to track bank and charge account balances with dedicated keys:

Memory 1 [CHK] [DEP] [BAL] [A]
Memory 2 [PMT] [CHG] [BAL] [B]
Memory 3 [PMT] [CHG] [BAL] [C]
Total sum of Memories [GT]

While the NS103 Data Checker was based on proprietary technology, introduced NEC of Japan with the uPD1833G in 1980 a single-chip calculator circuit that created the blueprint for checkbook-sized Account Manager calculators and thereupon the market got swamped with products based on this design. The uPD1833G simplified the use of the memories by removing the redundant [A], [B], and [C] keys and replaced the inconvenient three-way power-switch of the NS103 Data Checker with two dedicated [ON] and [OFF] keys and a [DS] key to toggle between two entry modes:

Indicator (--) Floating decimal with manual insertion of the decimal using the [.] key
Indicator (AM) Add mode with the decimal automatically put in the dollars and cents position (0.00)

Even the successor of the NS103, known as NS103A, switched its internals to the uPD1833G but we feature some more Account Manager calculators in the Datamath Calculator Museum based on this technology:

Canon Checkbook - Missing the Toggle Key for the decimal mode
Royal LCB 841 - The Art of Perfection in Japan
Royal LCB 835 - Just one Memory (uPD1831G)
Texas Instruments TI-2200 Checkwriter - Late, but not too late
Unisonic LC 262CK Check Master - Credit Card sized

NEC of Japan lost some market share with their design for Account Manager calculators in the Eighties, when competitors like Hitachi and Sharp introduced similar chips and finally lost the business completely to Toshiba's "Solar Cells" compatible design. Find more Account Manager calculators in the Datamath Calculator Museum:

Canon Checkbook II - Toshiba inside
Casio CB-80 - Hitachi inside
Unisonic LC 224CK Check Master- Sharp Inside
This Texas Instruments TI-2200 II Checkwriter - Toshiba + Solar cells = Winning formula

Dismantling the featured TI-2200 II manufactured in March 1987 by Compal Electronics in Taiwan reveals a clean design centered around a Toshiba T7752S single-chip calculator circuit soldered on a double-sided printed circuit board (PCB) and powered by four solar cells and a small LR54 (LR1130) backup battery.
PCB-Mark 308

Inspecting the PCB of this TI-2200 II manufactured in March 1987 brought our attention to a small mark reading 308 II-02, most likely a reference to Type 308, TI-2200 II, and Revision 2 of the design (schematics and layout). We noticed the PCB-Mark 308 during our research on the PCBs of a lot of more or less identical Account Managers:

308-15 TI-2200 II (Thailand, June 1995)
308-16 Royal CBC 80NT (Taiwan), Unisonic LC 266CK (Taiwan)
308-17 Royal CBC 80 (Thailand)
308-18 Olivetti DII (Thailand), Royal CBC 80 (Thailand), Royal CBC-95 (Thailand), Royal/Olivetti DII, Radio Shack EC-430 (Thailand)
308 II-02 TI-2200 II (Taiwan, March 1987)

Comparing the 5 known Revisions of this PCB reveals an interesting difference: Both Revisions used in the TI-2200 II (308 II-02 and 308-15) feature a tantalum capacitor in the obsolete holder for the second battery, while this component is missing with the PCB Revisions 16, 17, and 18 used with the other brands. We suspect that the additional tantalum capacitor allows changing the backup battery w/o losing the content of the 3 Memories for the account balances.

Please find an overview of the PCB-Marks we discovered so far on Account Manager calculators.

OEM Design 308

This TI-2200 II CheckWriter is obviously based on an OEM design shared with other manufacturers, find an overview of the known brands/models here:

Citizen CBL-200 Olivetti DII
Radio Shack EC-430
(65-570)
Radio Shack EC-430
(65-570A)
Royal CBC 80NT Royal CBC 80
Royal CBC 95 Royal/Olivetti CBC 80
Texas Instruments TI-2200 II Unisonic LC 266CK

Learn more about single-chip calculator circuits used in Account Manager Calculators.

Texas Instruments entered the market of Checkbook Calculators with the TI-1880 Checkwriter in 1981, almost 3 years after National Instruments' NS103, but it was nothing else than a basic calculator put in a fancy wallet. The TI-2200 Checkwriter introduced in October 1982 added Account Manager functionality with three permanent (till you remove the batteries) Memories and started a very successful product line. We discovered as of now seven different family members:

1982 - 1984: TI-2200 Silver, unknown OEM, Americas market
1982 - 1984: TI-2200 Silver, unknown OEM, European market
1984 - 1986: TI-2200 Gold, Compal Electronics Taiwan, Americas market
1984 - 1986: TI-2200 II Gold, Compal Electronics Taiwan, European market
1986 - 1991: TI-2200 II Solar cells, Compal Electronics Taiwan, Global market
1991 - 1996: TI-2200 II Solar cells, Compal Electronics Thailand, Global market
1996 - 2002: TI-2200+, Inventec Corporation Malaysia, Global market

Don't miss the Corvus CheckMaster introduced by Mostek already in 1975. This rare product retains the balance of your memory even when shut off but uses power-hungry electronics.

The TI-2200 II is featured in the Texas Instruments Incorporated sales catalog CL-1233 dated 1994.



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

Joerg Woerner, December 26, 2002 and February 11, 2020. No reprints without written permission.