[1.10] Patents For Ti-89 And Ti-92 - Texas Instruments TI-89 Tip List

[1.10] Patents for TI-89 and TI-92 Plus
This section contains abstracts of the six patents listed on the calculators, and additonal patents which
may apply to graphing calculators in general. All the patents are assigned to Texas Instruments. For
the full patent text including claims and figures, search by patent number at the US Patent and
Trademark Office, here:
http://www.uspto.gov
Note that all the patents listed on the calculators issued between 1974 and 1982. I only present the
abstracts, but it is the patent claims that specify the patented properties of the invention. Note also that
two listed patents have the same title and abstract. This is not uncommon, and the claims section of
the patents would describe the difference between the two inventions.
Jack Kilby is listed as an inventor on patent 3819921. Jack Kilby invented the integrated circuit, and
was awarded the 2000 Nobel prize in physics for that work. For more information on Mr. Kilby, go here:
http://www.ti.com/corp/docs/kilbyctr/jackstclair.shtml
TI has been granted at least 89 patents with the word calculator in the title. If you are interested in the
history of calculators in general and TI in particular, these may provide hours of interesting reading.
3819921: Miniature electronic calculator
Inventor(s): Kilby; Jack S., Merryman; Jerry D., Van Tassel; James H.
Issued/Filed Dates: June 25, 1974 / Dec. 21, 1972
Binary-coded decimal electronic calculator capable of adding, subtracting, multiplying and dividing
with some degree of automatic decimal point placement to provide a visual display of answers of up
to 12 decimal digits. The decimal digits are serially displayed at a speed compatible with the
calculator operations. The parts of the calculator are so adapted electrically and mechanically in
relation to each other to result in a minature portable battery operated calculator of extremely small
dimensions for example the outside case dimensions of 41/4 inches by 61/8 inches by 13/4 inches
and very low weight of about 45 ounces, having a calculating capability only before obtainable in
calculators of much larger size and weight while retaining mechanical and operational simplicity.
Some significant aspects of the calculator are the primary electronics embodied in an integrated
semiconductor circuit array located in substantially one plane for performing the arithmetic
calculations and generating the control signals, a keyboard input arrangement located in
substantially one plane parallel to the integrated semiconductor circuit array for producing unique
electrical signals corresponding to number and command entries and a visual display using a
semiconductor array, as for a thermal printer for printout.
3921142: Electronic calculator chip having test input and output
Inventor(s): Bryant; John D., Hartsell; Glenn A.,
Issued/Filed Dates: Nov. 18, 1975 / Sept. 24, 1973
An MOS/LSI semiconductor chip for providing the functions of an electronic calculator includes a
data memory, an arithmetic unit for executing operations on data from the memory, and a control
arrangement for defining the functioning of the machine including a ROM for storing a large number
of instruction words, an instruction register for receiving instruction words from the ROM and
reading out parts to various sections of the control arrangement, and an address register for
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