Wikipedia:Reference desk/Archives/Science/2018 June 11

= June 11 =

When were calculators minaturizable to the size of a stack of several credit cards? When did those get cheap?
I've seen a plastic 1990s calculator like that that said "Credit Card Calculator" and looked affordable and I've seen an ancient LCD one barely at the memory keys level of features yet was very thick and "c. turn of the century scientific calculator production values" looking and I know the physically tiny Intel 4004 was enough for a calculator in 1971 (not a cheap one obviously) so I'm a bit confused about the miniaturization timescale. Also, how thin did ≤7.171875 square inch calculators ever get? Sagittarian Milky Way (talk) 21:33, 11 June 2018 (UTC)


 * Here's the Vintage Calculator website, who cite the Mostek MM5758N (circa 1969), and similar single-circuit calculator IC products, as the key enabling technologies.
 * The size of the final consumer-product was not actually limited by the size of the circuitry for a few more decades, when product miniaturization was taken to its extreme.
 * Nimur (talk) 22:25, 11 June 2018 (UTC)


 * Calculator size is and was limited by display, button, and battery sizes, not IC size. Credit-card calculators used film buttons, LCD displays, and thin solar cells instead of batteries. Slightly thicker calculators could use thin batteries instead of the older bigger batteries because newer LCDs and ICs used less power. -Arch dude (talk) 04:21, 12 June 2018 (UTC)


 * See Calculator watch 196.213.35.147 (talk) 05:59, 12 June 2018 (UTC)

From my faint memory: mid 1970s (ca 75, 76), green LED display calculator, ca 15cm long, 8cm wide 2cm high, eight or 12 digits, limited functions (+-*/, sqrt, M+, M-): price then reached an affordable U$ 25. Scientific calculators (market leader: Texas Instruments) maybe three times as much. Quickly prices fell further, LCD replaced with LED, thinner (less than 1cm), price maybe U$ 5. Credit card format achieved before the end of the 1980s with cheap solar cells. Price something nominal, maybe U$2 for purchase of single unit. They generally were given away as advertising gimmick. Oalexander (talk) 05:39, 14 June 2018 (UTC)