Talk:Seven-segment display

reader feedback
There are quite a few feedback comments requesting specific information on pin-out, how to implement, etc. Much of this is simply beyond the scope of what Wikipedia is about, I suspect they want help with their homework. What they need to do is read the datasheet for the particular hardware they have. If anybody has a good way (or reference) to address this issue, it appears people would appreciate it. Can we point them to a more appropriate forum? (I like this concept of reader feedback). Nerfer (talk) 05:00, 10 January 2013 (UTC)
 * Cheer up. As soon as we have all the List of 7400 series integrated circuits pinouts and data sheets in the Wikipedia, I'm sure the same crew will turn its attention to another Wikipartslist. After all, there can't be more than 7 or 8 thousand different types of seven-segment display; what could be more encyclopediac than that? --Wtshymanski (talk) 14:24, 10 January 2013 (UTC)

character representations
"but only few representations are unambiguous and intuitive at the same time: uppercase A, B, C, E, F, G, H, I, J, L, O, P, S, U, Y, Z, and lowercase a, b, c, d, g, h, i, n,o, q, r, t, u"
 * Does anyone have a source for this claim along with a list of which representation for each is considered unique and intuitive?


 * Furthermore, I've seen some displays use BCDFG as a way to represent lowercase Y. Even if it weren't that common, isn't it both unambiguous and intuitive? — Preceding unsigned comment added by 88.20.221.163 (talk) 19:45, 7 August 2023 (UTC)

Elevators
Are there any elevators with seven-segment displays? --84.61.165.65 (talk) 15:08, 18 January 2010 (UTC)

Why would anyone delete the hexadecimal encoding from A-G??
I really want to know what he/she was thinking. I would add them by myself but it seemed hard to understand managing tables. 78.181.36.202 (talk) 02:09, 30 April 2010 (UTC)
 * As FYI, hexadecimal does not include 'G'. But to your point, somebody has included A-F again. Nerfer (talk) 02:43, 16 November 2012 (UTC)

how much current needed for seven segment 5"?
anybody knows? —Preceding unsigned comment added by 125.164.215.198 (talk • contribs)
 * For LED 7 segement displays the manufacturers datasheets will give you maximum continuous and peak currents. Typically large displays have multiple LEDs per segment and have them in series (or for the really big displays a combination of series and paralell) so will need much higher drive voltages than smaller displays. Watch out for the decimal point as it will often have much lower ratings than the rest of the segments.
 * LCDs are more complex requiring an AC drive, once again you need to read the manufacturers datasheet. Plugwash (talk) 12:39, 1 September 2010 (UTC)

Needs work
This article contains too many technical details, and its structure is weak.

Facts that are interesting:
 * Physical description,
 * Examples of all of the digit shapes and commonly-used letter shapes,
 * History,
 * List of technologies that have been used to implement 7-seg displays,
 * Pictures of 7-seg displays.
 * The fact that manufacturers have tried varying slant and segment shapes to improve readability.

Marginally interesting trivia (should be moved toward the end of the article):
 * The fact that the pins/electrical-connections to a packaged unit can be multiplexed,
 * That some packages are designed to be handled and/or mounted in the same manner as standard integrated circuit packages,

Facts that only get in the way:
 * Picture of all of the 128 possible states,
 * Any more than one sentence about varying slant and segment shapes to improve readability,
 * Any sentence acknowledging that LEDs have cathodes or anodes,
 * That a molded plastic light bar may be illuminated by one or more LEDs,
 * That LEDs may be connected in series or in parallel or some combination of the above.
 * That different manufacturers have assigned different letter names to the segments on their data sheets,
 * That the state of 7 segments + 1 decimal point can be encoded in an 8-bit byte,
 * That some packages may have fewer pins than a standard IC socket is designed to accept.
 * That the scanning of display segments on a pocket calculator can be linked to the keyboard scanning,
 * That any kind of decoding logic may be incorporated into the same package as the display.

Plus one important fact that is missing from the article


 * They're cheap. No matter what technology you use to implement it, a 7-seg display is the simplest known way to display digits 0–9.  Simple equals inexpensive.  The difference may not be significant if you're using off-the-shelf parts to build a one-off or a small production run, but if you manufacture on a scale where an engineer can earn his/her own salary for a year by shaving a tenth of a penny off the unit cost, then 7-segment is the only logical choice.  — Preceding unsigned comment added by 129.42.208.179 (talk) 13:10, 25 September 2013 (UTC)

Alternative glyphs
This article seems to be very heavily based (not to say, a copy-paste of) the reference [1] = [2] ("7 seg tutorial"), and therefore strongly biased/deficient in some aspects. There and here is mentioned that other glyphs do exist, and I agree that the other variants are "negligible" (maybe aside the 6 without top segment), but this is certainly not true for the "7" with upper left "|", which, I think, is FAR more common than the one without. I think (almost?) all pocket calculators (see that page: all pictures confirm this) and most wireless phone handsets (I have one right at hand) use that one rather than the one without. &mdash; MFH:Talk 13:29, 29 December 2013 (UTC)

4511 decoder ICs
Documentation for various 4511 chips don't match each other for numbers 6 & 9.


 * this CD4511 video doesn't show a tail for 6 & 9 - https://www.youtube.com/watch?v=CFsMWGUVLXA


 * this CD4511B datashet doesn't show a tail for 6 & 9 in the character set, but the logic table says it should have a tail - https://www.ti.com/lit/ds/symlink/cd4511b.pdf?ts=1694050666899


 * this CD74HC4511 & CD74HCT4511 shows a tail for 6 & 9 in the character set and logic table - https://www.ti.com/lit/ds/symlink/cd74hc4511.pdf?ts=1693998795416


 * this CD74HC4511 & CD74HCT4511 doesn't show a tail in the character set, but the logic tables says it should have a tail - https://assets.nexperia.com/documents/data-sheet/74HC_HCT4511.pdf

• Sbmeirow  •  Talk  • 01:54, 7 September 2023 (UTC)


 * I think a better question is to ask here: is the Decoder ICs section needed? This seems like such indiscriminate information to provide in the table. The article is about seven-segment displays. A lot of the differences presented of the displays can be summarized that there's various ways the letters and numbers are presented depending on the companies. Mentioning there's tails, no tails, seems so unnecessary here and within the WP:IINFO realm. – The Grid  ( talk )  21:08, 9 October 2023 (UTC)