News Archive - Introducing the Cal-Tex CT5005 Calculator Chip
Cal-Tex Semiconductor, Inc. CT5005 Calculator IC Introduction
Electronics Magazine, May, 22, 1972
An article introducing the Cal-Tex Corp. CT5005 calculator-on-a-chip IC.
Cal-Tex Semiconductor, Inc. was an integrated circuit manufacturing company
founded in 1971, located in Santa Clara, California. The company initially
specialized in developing single-chip electronic calculator and digital
electronic clock integrated circuits. The calculator ICs were
mostly used in low-cost, off-brand desktop and handheld electronic
calculators due to the very low cost of the ICs in production quantities.
Cal-Tex was acquired by IC pioneer Fairchild Semiconductor in 1975.
The CT5005 chip was among a range of calculator ICs designed and
manufactured by Cal-Tex that began with the CT5001, and included the CT5002,
CT5005, CT5007, CT5012, CT5030, CT5031, CT5032, and CT5037.
The CT5005 chip is housed in a 28-pin dual-inline plastic package. It
has twelve digits of capacity and provides the standard four math
functions along with an accumulating memory register with [M+] (add to
memory), [M-] (subtract from memory), [RM] (recall memory), and [CM]
(clear memory) functions. It uses arithmetic logic with fixed decimal point
selectable at zero through five digits behind the decimal point. It provides
leading zero suppression, and is designed to drive a seven-segment multiplexed
display.
