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{{short description|Form of electronic display device for displaying decimal numerals}}
[[Image:Seven segment 02 Pengo.jpg|280px|thumb|right|A typical 7-segment [[light-emitting diode|LED]] display component, with decimal point.]]
{{Use dmy dates|date=April 2019|cs1-dates=y}}
A '''seven-segment display''' (abbreviation: "'''7-seg'''(ment) display"), less commonly known as a '''seven-segment indicator''', is a form of [[display device]] that is an alternative to the more complex [[dot-matrix]] displays. Seven-segment displays are commonly used in [[electronics]] as a method of displaying [[decimal]] numeric feedback on the internal operations of devices.
[[File:Seven segment 01 Pengo.jpg|thumb|right|A typical 7-segment [[light-emitting diode|LED]] display component, with decimal point in a wide [[dual in-line package|DIP]]-10 package]]
A '''seven-segment display''' is a [[display device]] for [[Arabic numerals]], less complex than a device that can show more characters such as [[dot matrix display]]s. Seven-segment displays are widely used in [[digital clock]]s, [[Elevator|elevators]], electronic meters, basic calculators, and other electronic devices that display numerical information.<ref>{{cite web |title=Seven Segment Displays |url=https://sharedserver.rsd17.org/teacherwebpages/ryankish/Shared%20Documents/2.3%20Date%20of%20Birth%20machine/Seven-segment%20displays.ppt |url-status=dead |archive-url=https://web.archive.org/web/20120404071304/https://sharedserver.rsd17.org/teacherwebpages/ryankish/Shared%20Documents/2.3%20Date%20of%20Birth%20machine/Seven-segment%20displays.ppt |archive-date=2012-04-04}}</ref>
 
==History==
==Concept and visual structure==
Seven-segment representation of figures can be found in [[patent]]s as early as 1903 (in {{US patent|1126641}}), when Carl Kinsley invented a method of telegraphically transmitting letters and numbers and having them printed on tape in a segmented format. In 1908, F. W. Wood invented an 8-segment display, which displayed the number 4 using a diagonal bar ({{US patent|974943}}). In 1910, a seven-segment display illuminated by incandescent bulbs was used on a power-plant boiler room signal panel.<ref>{{cite journal |author-first=Warren O. |author-last=Rogers |title=Power Plant Signalling System |journal=Power and the Engineer |volume=32 |number=5 |date=1910-02-01 |pages=204–206 |url=https://books.google.com/books?id=0sIfAQAAMAAJ&pg=PA204 |access-date=6 October 2016 |url-status=live |archive-url=https://web.archive.org/web/20140331102649/http://books.google.com/books?id=0sIfAQAAMAAJ&pg=PA204 |archive-date=31 March 2014}}</ref> They were also used to show the dialed telephone number to operators during the transition from manual to automatic telephone dialing.<ref>{{cite journal |author-last=Clark |author-first=E. H. |title=Evolution of the Call-Indicator System |journal=Bell Laboratories Record |volume=8 |number=5 |date=December 1929 |pages=171–173 |url=http://www.americanradiohistory.com/Archive-Bell-Laboratories-Record/20s/Bell-Laboratories-Record-1929-12.pdf |access-date=2015-12-19 |url-status=live |archive-url=https://web.archive.org/web/20240413141700/http://www.americanradiohistory.com/Archive-Bell-Laboratories-Record/20s/Bell-Laboratories-Record-1929-12.pdf |archive-date=2024-04-13}}</ref> They did not achieve widespread use until the advent of [[light-emitting diode|LED]]s in the 1970s.
[[Image:7 segment display labeled.svg|thumb|right|150px|The individual segments of a seven-segment display.]]
A seven segment display, as its name indicates, is composed of seven elements. Individually on or off, they can be combined to produce simplified representations of the [[Arabic numerals|Hindu-Arabic numerals]]. Often the seven segments are arranged in an ''oblique'', or ''[[italic type|italic]]'', arrangement, which aids readability.
 
[[File:Incandescent light seven-segment display prPNr°17.jpg|thumb|upright|Filament seven-segment display]]
Each of the numbers [[0 (number)|0]], [[6 (number)|6]], [[7 (number)|7]] and [[9 (number)|9]] may be represented by two or more different glyphs on seven-segment displays.
Some early seven-segment displays used incandescent filaments in an evacuated bulb; they are also known as numitrons.<ref>{{cite web |title=IEE Apollo DA-2110 Numitron Tube (DA2110, RCA DR-2110) - Industrial Alchemy |website=industrialalchemy.org |url=https://www.industrialalchemy.org/articleview.php?item=65 |access-date=2020-04-15 |url-status=live |archive-url=https://web.archive.org/web/20200915201814/http://www.industrialalchemy.org/articleview.php?item=65 |archive-date=2020-09-15}}</ref> A variation (minitrons) made use of an evacuated [[potting (electronics)|potted]] box. Minitrons are filament segment displays that are housed in DIP ([[dual in-line package]]) packages like modern LED segment displays. They may have up to [[sixteen-segment display|16 segments]].<ref>{{cite web |title=Wamco KW-105AL Alphanumeric Minitron Display - Industrial Alchemy |website=industrialalchemy.org |url=https://www.industrialalchemy.org/articleview.php?item=777 |access-date=2020-04-15 |url-status=live |archive-url=https://web.archive.org/web/20200915204740/http://www.industrialalchemy.org/articleview.php?item=777 |archive-date=2020-09-15}}</ref><ref>{{cite web |title=Numitron Tube Tutorial |date=21 December 2011 |url=https://hackaday.com/2011/12/21/numitron-tube-tutorial/ |access-date=14 April 2020 |url-status=live |archive-url=https://web.archive.org/web/20180925230213/https://hackaday.com/2011/12/21/numitron-tube-tutorial/ |archive-date=25 September 2018}}</ref><ref>{{cite web |title=Incandescent Displays – the Vintage Technology Association |url=http://www.decadecounter.com/vta/tubepage.php?item=10 |access-date=14 April 2020 |url-status=usurped |archive-url=https://web.archive.org/web/20180217005226/http://www.decadecounter.com/vta/tubepage.php?item=10 |archive-date=17 February 2018}}</ref> There were also segment displays that used small incandescent light bulbs instead of LEDs or incandescent filaments. These worked similarly to modern LED segment displays.<ref>{{cite web |title=Alco MSM-5A Mosaic Indicator Incandescent Display - Industrial Alchemy |website=industrialalchemy.org |url=https://www.industrialalchemy.org/articleview.php?item=845 |access-date=2020-04-15 |url-status=live |archive-url=https://web.archive.org/web/20200915211829/http://www.industrialalchemy.org/articleview.php?item=845 |archive-date=2020-09-15}}</ref>
 
[[Vacuum fluorescent display]] versions were also used in the 1970s.<ref>{{cite web |title=General Electric Y1938 – the Vintage Technology Association |url=http://www.decadecounter.com/vta/articleview.php?item=94 |access-date=13 November 2020 |url-status=usurped |archive-url=https://web.archive.org/web/20160611100808/http://www.decadecounter.com/vta/articleview.php?item=94 |archive-date=11 June 2016}}</ref>
[[Image:Seven segment display-animated.gif|thumb|left|85px|LED-based 7-segment display showing the 16 [[hexadecimal|hex]] digits.]]
The seven segments are arranged as a [[rectangle]] of two vertical segments on each side with one horizontal segment on the top and bottom. Additionally, the seventh segment bisects the rectangle horizontally. There are also [[fourteen-segment display]]s and [[sixteen-segment display]]s (for full [[wikt:alphanumeric|alphanumeric]]s); however, these have mostly been replaced by [[dot-matrix]] displays.
 
Many early (c. 1970s) LED seven-segment displays had each digit built on a single [[die (integrated circuit)|die]]. This made the digits very small. Some included magnifying lenses in the design to try to make the digits more legible.<ref>{{cite web |title=Litronix Surface Mount Wristwatch LED Display – Industrial Alchemy |url=https://www.industrialalchemy.org/articleview.php?item=3081 |access-date=16 April 2020 |url-status=live |archive-url=https://web.archive.org/web/20180831152511/http://industrialalchemy.org/articleview.php?item=3081 |archive-date=31 August 2018}}</ref><ref>{{cite web |title=Litronix DL330 Series LED Displays (Siemens DL340M) - Industrial Alchemy |url=https://www.industrialalchemy.org/articleview.php?item=787 |access-date=16 April 2020 |url-status=live |archive-url=https://web.archive.org/web/20180304050126/https://www.industrialalchemy.org/articleview.php?item=787 |archive-date=4 March 2018}}</ref> Other designs used 1 or 2 dies for every segment of the display.<ref>{{cite web |title=Soviet AL304V Surface Mount LED - Industrial Alchemy |url=https://www.industrialalchemy.org/articleview.php?item=1167 |access-date=2024-01-21 |url-status=live |archive-url=https://web.archive.org/web/20220928122454/https://www.industrialalchemy.org/articleview.php?item=1167 |archive-date=2022-09-28}}</ref><ref>{{cite web |title=Texas Instruments TIA8447 LED Display - Industrial Alchemy |url=https://www.industrialalchemy.org/articleview.php?item=773 |access-date=2024-01-21 |url-status=live |archive-url=https://web.archive.org/web/20220529091352/https://www.industrialalchemy.org/articleview.php?item=773 |archive-date=2022-05-29}}</ref>
The segments of a 7-segment display are referred to by the letters A to G, as shown to the right, where the optional DP [[decimal point]] (an "eighth segment") is used for the display of non-integer numbers.
 
The seven-segment pattern is sometimes used in posters or tags, where the user either applies color to pre-printed segments, or applies color through a seven-segment digit [[stencil|template]], to compose figures such as product prices or telephone numbers.
The animation to the left cycles through the common glyphs of the ten decimal numerals and the six [[hexadecimal]] "letter digits" (A–F). It is an image sequence of a "LED" display, which is described technology-wise in the following section. Notice the variation between uppercase and lowercase letters for A–F; this is done to obtain a unique, unambiguous shape for each letter.
 
For many applications, dot-matrix [[liquid-crystal display]]s (LCDs) have largely superseded LED displays in general, though even in LCDs, seven-segment displays are common. Unlike LEDs, the shapes of elements in an LCD panel are arbitrary since they are formed on the display by [[photolithography]]. In contrast, the shapes of LED segments tend to be simple [[rectangle]]s, because they have to be physically moulded to shape, which makes it difficult to form more complex shapes than the segments of seven-segment displays. However, the easy recognition of seven-segment displays, and the comparatively high visual [[contrast (vision)|contrast]] obtained by such displays relative to dot-matrix digits, makes seven-segment multiple-digit LCD screens very common on basic [[calculator]]s.
 
The seven-segment display has inspired [[type design]]ers to produce typefaces reminiscent of that display (but more legible), such as [[New Alphabet]], "DB LCD Temp", "ION B", etc.
 
Seven-segment displays, which use a restricted range of letters that look like (upside-down) digits, are commonly used by school children to form words and phrases using a technique known as "[[calculator spelling]]."
 
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| [[Gas station]] price display
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| File:SHARP ELSIMATE EL-W221.jpg
| [[Calculator]] that has a tail on the "7" digit
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| [[Apollo Guidance Computer]] control panel reproduction
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| Marantz CD63SE [[CD player]] with a [[vacuum fluorescent display]] in test mode
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| Marantz CC-45 [[CD player]] display
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==Implementations==
Seven-segment displays may use a [[liquid-crystal display]] (LCD), a [[light-emitting diode]] (LED) for each segment, an [[electrochromic devices#Other displays|electrochromic display]], or other light-generating or -controlling techniques such as [[cold cathode]] gas discharge (neon) ([https://www.panaplex.co.uk/ Panaplex]), [[vacuum fluorescent display|vacuum fluorescent]] (VFD), [[incandescent lamp|incandescent filaments]] (Numitron), and others. For [[gasoline]] price totems and other large signs, electromechanical seven-segment displays made up of electromagnetically flipped light-reflecting segments are still commonly used. A precursor to the 7-segment display in the 1950s through the 1970s was the cold-cathode, neon-lamp-like [[nixie tube]]. Starting in 1970, [[RCA]] sold a display device known as the ''{{Visible anchor|Numitron}}'' that used incandescent filaments arranged into a seven-segment display.<ref name="Numintron 1974">{{cite journal |date=1974-06-07 |title=Advert for RCA NUMITRON Display Devices |journal=Electronic Design |publisher=Hayden |volume=22 |issue=12 |page=163 |url=https://commons.wikimedia.org/wiki/File:RCA_Numitron_display_device_June_1974.jpg |access-date=22 June 2012 |url-status=live |archive-url=https://web.archive.org/web/20140331112707/http://commons.wikimedia.org/wiki/File:RCA_Numitron_display_device_June_1974.jpg |archive-date=31 March 2014}}</ref> In USSR, the first electronic calculator "Vega", which was produced from 1964, contains 20 decimal digits with seven-segment [[electroluminescent display]].<ref>{{cite web |title=Museum of Soviet Calculators - VEGA |date=29 September 2010 |url=http://www.taswegian.com/MOSCOW/vega.html |url-status=dead |archive-url=https://web.archive.org/web/20100929142141/http://www.taswegian.com/MOSCOW/vega.html |archive-date=29 September 2010}}</ref>
 
In a simple LED package, typically all of the [[cathode]]s (negative terminals) or all of the [[anode]]s (positive terminals) of the segment LEDs are connected and brought out to a common pin; this is referred to as a "common cathode" or "common anode" device.<ref name="Westermann_Tabellen"/> Hence a 7 segment plus decimal point package will only require nine pins, though commercial products typically contain more pins, and/or spaces where pins would go, in order to match standard [[integrated circuit|IC]] sockets. Integrated displays also exist, with single or multiple digits. Some of these integrated displays incorporate their own internal [[binary decoder|decoder]], though most do not: each individual LED is brought out to a connecting pin as described.
[[Image:Incandescent light seven-segment display.jpg|thumb|An ''incandescent light'' type early seven-segment displays.]]
[[Image:Fuel prices.jpg|thumb|right|A mechanical seven-segment display for displaying [[petrol|gas/petrol]] prices.]]
Seven-segment displays may use [[liquid crystal display]] (LCD), arrays of [[light-emitting diode]]s (LEDs), and other light-generating or controlling techniques such as such as cold [[cathode]] gas discharge, vacuum fluorescent, incandescent filaments, and others. For [[gasoline]] price totems and other large signs, electromagnetically flipped light-reflecting segments (sometimes called "vanes") are still commonly used. An alternative to the 7-segment display in the [[1950s]] through the [[1970s]] was the cold-cathode, neon-lamp-like [[nixie tube]]. Starting in 1970, [[RCA]] sold a display device known as the ''Numitron'' that used incandescent filaments arranged into a seven-segment display. <ref>[http://www.decodesystems.com/numitron.html Numitron Readout]</ref>
 
Multiple-digit LED displays as used in pocket calculators and similar devices used [[multiplexed display]]s to reduce the number of I/O pins required to control the display. For example, all the anodes of the A segments of each digit position would be connected together and to a [[driver circuit]] pin, while the cathodes of all segments for each digit would be connected. To operate any particular segment of any digit, the controlling integrated circuit would turn on the cathode driver for the selected digit, and the anode drivers for the desired segments; then after a short blanking interval the next digit would be selected and new segments lit, in a sequential fashion. In this manner an eight digit display with seven segments and a decimal point would require only 8 cathode drivers and 8 anode drivers, instead of sixty-four drivers and IC pins.<ref>e.g. [http://pdf1.alldatasheet.com/datasheet-pdf/view/170106/VISHAY/TDCR1050M.html DCR 1050m] {{Webarchive|url=https://web.archive.org/web/20140331105445/http://pdf1.alldatasheet.com/datasheet-pdf/view/170106/VISHAY/TDCR1050M.html |date=31 March 2014}}</ref> Often in pocket calculators the digit drive lines would be used to scan the keyboard as well, providing further savings; however, pressing multiple keys at once would produce odd results on the multiplexed display.
In a simple LED package, each LED is typically connected with one terminal to its own pin on the outside of the package and the other LED terminal connected in common with all other LEDs in the device and brought out to a shared pin. This shared pin will then make up all of the cathodes (negative terminals) OR all of the anodes (positive terminals) of the LEDs in the device; and so will be either a "Common Cathode" or "Common Anode" device depending how it is constructed. Hence a 7 segment plus DP package will only require nine pins to be present and connected.
 
{{Gallery
Integrated displays also exist, with single or multiple digits. Some of these integrated displays incorporate their own internal decoder, though most do not &ndash; each individual LED is brought out to a connecting pin as described. Multiple-digit LED displays as used in pocket calculators and similar devices used [[multiplexed display]]s to reduce the number of IC pins required to control the display. For example, all the anodes of the A segments of each digit position would be connected together and to a driver pin, while the cathodes of all segments for each digit would be connected. To operate any particular segment of any digit, the controlling integrated circuit would turn on the cathode driver for the selected digit, and the anode drivers for the desired segments; then after a short blanking interval the next digit would be selected and new segments lit, in a sequential fashion. In this manner an eight digit display with seven segments and a decimal point would require only 8 cathode drivers and 8 anode drivers, instead of sixty-four drivers and IC pins. Often in pocket calculators the digit drive lines would be used to scan the keyboard as well, providing further savings; however, pressing multiple keys at once would produce odd results on the multiplexed display.
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| A [[multiplexing|multiplexed]] 4-digit, seven-segment display with only 12 pins
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| A 4-digit display scanning by columns to make the number 1.234
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| X-Ray of an 8-digit 7-segment multiplexed LED display from a 1970s calculator
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==Characters==
Seven segment displays can be found in [[patent]]s as early as 1908 (in {{US patent|974943}}, F W Wood invented an 8-segment display, which displayed the number 4 using a diagonal bar), but did not achieve widespread use until the advent of LEDs in the 1970s. They are sometimes even used in unsophisticated displays like cardboard "For sale" signs, where the user either applies color to pre-printed segments, or (spray)paints color through a seven-segment digit [[template]], to compose figures such as product prices or telephone numbers.
{{Main|Seven-segment display character representations}}
[[File:7 Segment Display with Labeled Segments.svg|thumb|150px|Segment names of a seven-segment display with an eighth Decimal Point segment]] [[File:Slanted7SegmentDisplayWithDot.svg|thumb|150px|Slanted red seven-segment display with dot]]
The seven segments are arranged as a rectangle, with two vertical segments on each side and one horizontal segment each at the top, middle, and bottom. Often the rectangle is ''[[oblique type|oblique]]'' (slanted), which may aid readability. In most applications, the segments are of nearly uniform shape and size (usually elongated [[hexagon]]s, though [[trapezoid]]s and [[rectangle]]s can also be used); though in the case of [[adding machine]]s, the vertical segments are longer and more oddly shaped at the ends, to try to make them more easily readable. The seven elements of the display can be lit in different combinations to represent each of the [[Arabic numerals]].
 
The individual segments are referred to by the letters "a" to "g", and an optional [[decimal point]] (an "eighth segment", referred to as DP) is sometimes used for the display of non-integer numbers.<ref>{{cite web |title=Seven Segment Displays |url=http://www.sentex.ca/~mec1995/tutorial/7seg/7seg.html |access-date=2012-11-14 |url-status=dead |archive-url=https://web.archive.org/web/20120105025754/http://www.sentex.ca/~mec1995//tutorial/7seg/7seg.html |archive-date=2012-01-05}}</ref><ref name="Westermann_Tabellen">{{cite book |date=1999 |title=Elektrotechnik Tabellen Kommunikationselektronik |edition=3rd |publisher=[[Westermann Verlag]] |___location=Braunschweig, Germany |isbn=3142250379 |page=110}}</ref> A single byte can encode the full state of a seven-segment display, including the decimal point. The most popular bit encodings are ''gfedcba'' and ''abcdefg''. In the ''gfedcba'' representation, a byte value of 0x06 would turn on segments "c" and "b", which would display a "1".
For many applications, dot-matrix LCDs have largely superseded LED displays, though even in LCDs 7-segment displays are very common. Unlike LEDs, the shapes of elements in an LCD panel are arbitrary since they are formed on the display by a kind of printing process. In contrast, the shapes of LED segments tend to be simple [[rectangle]]s, reflecting the fact that they have to be physically moulded to shape, which makes it difficult to form more complex shapes than the segments of 7-segment displays. However, the high common recognition factor of 7-segment displays, and the comparatively high visual [[contrast (vision)|contrast]] obtained by such displays relative to dot-matrix digits, makes seven-segment multiple-digit LCD screens very common on basic [[calculator]]s.
 
[[File:7-segment.svg|thumb|16×8 grid showing the 128 states of a seven-segment display<ref name="elektor-UK_1981-72"/>]]
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===Decimal===
==Alphabetic display==
The [[numerical digit]]s 0 to 9 are the most common characters displayed on seven-segment displays. The most common patterns used for each of these are:<ref name="Nührmann_1991">{{cite book |title=Werkbuch Elektronik |language=de |author-first=Dieter |author-last=Nührmann |publisher=[[Franzis-Verlag GmbH]] |publication-place=Munich, Germany |___location=Achim, Bremen, Germany |date=1981 |edition=3 |isbn=3-7723-6543-4 |page=695}}</ref>
:{{7seg|0|10px|abcdef}} {{7seg|1|10px|bc}} {{7seg|2|10px|abdeg}} {{7seg|3|10px|abcdg}} {{7seg|4|10px|bcfg}} {{7seg|5|10px|acdfg}} {{7seg|6|10px|acdefg}} {{7seg|7|10px|abc}} {{7seg|8|10px|abcdefg}} {{7seg|9|10px|abcdfg}}
 
Alternative patterns: The numeral 1 may be represented with the left segments, the numerals 6 and 9 may be represented without a "tail", and the numeral 7 represented ''with'' a 'tail':<ref name="Casio fx-50F calculator">For example the fx-50F calculator from [[Casio]] and other models from the same manufacturer.</ref>
In addition to the ten numerals, seven segment displays can be used to show letters of the [[latin alphabet|latin]], [[cyrillic alphabet|cyrillic]] and [[greek alphabet]]s including [[punctuation]], but only few representations are unambiguous and intuitive at the same time: uppercase ''A'', ''B'', ''C'', ''E'', ''F'', ''G'', ''H'', ''I'', ''J'', ''L'', ''N'', ''O'', ''P'', ''S'', ''U'', ''Y'', ''Z'', and lowercase ''a'', ''b'', ''c'', ''d'', ''e'', ''g'', ''h'', ''i'', ''n'', ''ñ'', ''o'', ''q'', ''r'', ''t'', ''u''. Thus, [[ad hoc]] and corporate solutions dominate the field of alphabetics on seven-segment displays, which is usually not considered essential and only used for basic notifications, such as internal test messages on equipment under development. (For detailed tables of alternative seven-segment symbols for letters and punctuation, see the separate article [[seven-segment display character representations]].)
:{{7seg|1*|10px|ef}} {{7seg|6|10px|cdefg}} {{7seg|7|10px|abcf}} {{7seg|9|10px|abcfg}}
 
In Unicode 13.0, 10 codepoints had been given for segmented digits 0–9 in the [[Symbols for Legacy Computing]] block, to replicate early computer fonts that included seven-segment versions of the digits.<ref>[https://www.unicode.org/charts/PDF/U1FB00.pdf Official Unicode Consortium code chart] {{Webarchive|url=https://web.archive.org/web/20200605060757/http://www.unicode.org/charts/PDF/U1FB00.pdf |date=2020-06-05}} (PDF)</ref> The official reference shows the less-common four-segment "7".
Using a restricted range of letters that look like (upside-down) digits, seven-segment displays are commonly used by school children to form words and phrases using a technique known as "[[calculator spelling]]".
 
===Hexadecimal===
== In popular culture ==
The [[binary-coded decimal]] (BCD) 0 to 9 digit values require four binary bits to hold their values. Since four bits (2<sup>4</sup>) can hold 16 values, this means [[hexadecimal]] (hex) digits can be represented by four bits too.<ref name="Maxim_2008_MAX6955">{{cite web |title=Application Note 3210 – Quick-Start: Driving 7-Segment Displays with the MAX6954 |publisher=[[Maxim Integrated]] |orig-year=2004-06-25 |edition=3 |date=March 2008 |type=Application note |url=http://datasheets.maximintegrated.com/en/ds/MAX6955.pdf |access-date=2013-05-06 |url-status=live |archive-url=https://web.archive.org/web/20170320002007/https://datasheets.maximintegrated.com/en/ds/MAX6955.pdf |archive-date=2017-03-20}}</ref> Since there are a limited number of segments in seven-segment displays, a couple of the hexadecimal digits are required to be displayed as lowercase letters, otherwise the uppercase letter "B" would be the same as the digit "8", and the uppercase letter "D" would be the same as the digit "0".<ref name="Maxim">{{cite web |publisher=[[Maxim Integrated]] |title=Driving 7-Segment Displays |date=2004 |url=http://www.maximintegrated.com/app-notes/index.mvp/id/3210 |access-date=2017-03-20 |url-status=live |archive-url=https://web.archive.org/web/20170320000854/https://www.maximintegrated.com/en/app-notes/index.mvp/id/3210 |archive-date=2017-03-20}}</ref><ref name="TI_1974_SR-22">{{cite book |title=electronic hexadecimal calculator/converter SR-22 |publisher=[[Texas Instruments Incorporated]] |date=1974 |page=7 |edition=Revision A |id=1304-389 Rev A |url=http://www.datamath.net/Manuals/SR-22_US.pdf |access-date=2017-03-20 |url-status=live |archive-url=https://web.archive.org/web/20170320001329/http://www.datamath.net/Manuals/SR-22_US.pdf |archive-date=2017-03-20}}</ref><ref name="TI_1977_Programmer">{{cite book |title=electronic calculator – TI programmer |publisher=[[Texas Instruments Incorporated]] |date=1977 |page=7 |url=http://www.datamath.net/Manuals/TI-Programmer_US.pdf |access-date=2017-03-28 |url-status=live |archive-url=https://web.archive.org/web/20170328231050/http://www.datamath.net/Manuals/TI-Programmer_US.pdf |archive-date=2017-03-28}}</ref><ref name="TI_1981_LCD_Programmer">{{cite book |title=electronic calculator – TI LCD programmer |publisher=[[Texas Instruments Incorporated]] |date=1981 |page=8 |url=http://www.datamath.net/Manuals/LCD-Programmer_US.pdf |access-date=2017-03-28 |url-status=live |archive-url=https://web.archive.org/web/20170328231558/http://www.datamath.net/Manuals/LCD-Programmer_US.pdf |archive-date=2017-03-28}}</ref> The digit "6" must also be displayed with the topmost segment as {{7seg|6|10px}} to avoid ambiguity with the letter "b".
 
:{{7seg|A|10px}} {{7seg|b|10px}} {{7seg|C|10px}} {{7seg|d|10px}} {{7seg|E|10px}} {{7seg|F|10px}}
<!-- Deleted image removed: [[Image:24sevensegmentdisplay.jpg|thumb|right|150px|The logo of TV series ''24''.]] -->
Although their ubiquity make them appear on clock displays, medical instrumentation, and other digital devices commonly shown in [[motion picture]]s and [[television series]], seven-segment displays occasionally make more notable appearances as well.
 
Early decoder ICs often produced unintuitive patterns or duplicates of digits for 10-15,<ref>e.g. the [[List_of_7400-series_integrated_circuits#7448|74LS48]]</ref> as they were designed to use as few gates as possible and only required to produce 0-9.
*A glowing seven-segment display is used as the logo of the television series ''[[24 (TV series)|24]]'', showing the number 24 at the start of each episode, as well as being used for the six-digit military style real-time clock display, including a sound effect at the stroke of each second, during the episodes (particularly before and after the commercial breaks), to underscore the intended breathless nature of the action.
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==References=Letters===
Many letters of the [[Latin alphabet]] can be reasonably implemented on a seven-segment display. Though not every letter is available, it is possible to create many useful words. By careful choice of words, one can sometimes work around unavailable letters. Uppercase letters "I", "O", "S", "Z" conflict with the common seven-segment representation of digits "1", "0", 5", "2", and the lowercase letter "g" with digit "9". Upper case {{serif|I}} could be put on the left (as lower-case L is shown here) but this is not often done. Lowercase 'b' and 'q' are identical to the alternate numerical digits '6' and '9'.
<references />
 
:{| class="wikitable" style="text-align:center;background:#FFF"
|+ Latin alphabet
! !! A !! B !! C !! D !! E !! F !! G !! H !! I !! J !! K !! L !! M !! N !! O !! P !! Q !! R !! S !! T !! U !! V !! W !! X !! Y !! Z
|-
! Upper
| {{7seg|А|10px}} || || {{7seg|C|10px}} || || {{7seg|E|10px}} || {{7seg|F|10px}} || {{7seg|G|10px}} || {{7seg|H|10px}} || style="background: #FEE|{{7seg|I*|10px}} || {{7seg|J*|10px}} || || {{7seg|L|10px}} || {{nowrap|{{7seg|M|10px|abef}}{{7seg|M|10px|abcf}}}} || || style="background: #FEE|{{7seg|O|10px}} || {{7seg|P|10px}} || || || style="background: #FEE|{{7seg|S|10px}} || || {{7seg|U|10px}} || || {{nowrap|{{7seg|W|10px|cdef}}{{7seg|W|10px|bcde}}}} || || || style="background: #FEE|{{7seg|Z|10px}}
|-
! Lower
| {{7seg|a*|10px}} || {{7seg|b|10px}} || {{7seg|c|10px}} || {{7seg|d|10px}} || {{7seg|e|10px|abdefg}} || || style="background: #FEE|{{7seg|g*|10px}} || {{7seg|h|10px}} || {{7seg|i#|10px}} || {{7seg|j|10px|bcd}} || || {{7seg|l|10px}} || || {{7seg|n|10px}} || {{7seg|o|10px}} || || {{7seg|q|10px}} || {{7seg|r|10px}} || || {{7seg|t|10px}} || {{7seg|u|10px}} || || || || {{7seg|y|10px}} ||
|}
 
The following are some English word examples seen on actual electronic equipment (first line appeared on some [[CD player]]s):
== External links ==
 
*[http://www.dnatechindia.com/index.php/Tutorials/8051-Tutorial/7-Seg-Interfacing.html Seven Segment Interfacing To Microcontroller.]
:{{7seg|O|10px}}{{7seg|P|10px}}{{7seg|E|10px}}{{7seg|N|10px}}, {{7seg|C|10px}}{{7seg|L|10px}}{{7seg|O|10px}}{{7seg|S|10px}}{{7seg|E|10px}}, {{7seg|P|10px}}{{7seg|L|10px}}{{7seg|A|10px}}{{7seg|Y|10px|bcdfg}}, {{7seg|P|10px}}{{7seg|A|10px}}{{7seg|U|10px}}{{7seg|S|10px}}{{7seg|E|10px}}, {{7seg|S|10px}}{{7seg|H|10px}}{{7seg|U|10px}}{{7seg|F|10px}}{{7seg|F|10px}}{{7seg|L|10px}}{{7seg|E|10px}}, {{7seg|n|10px}}{{7seg|o|10px}} {{7seg|d|10px}}{{7seg|I|10px|bc}}{{7seg|S|10px}}{{7seg|C|10px}}
 
:{{7seg|S|10px}}{{7seg|t|10px}}{{7seg|A|10px}}{{7seg|r|10px}}{{7seg|t|10px}}, {{7seg|S|10px}}{{7seg|t|10px}}{{7seg|o|10px}}{{7seg|P|10px}}, {{7seg|r|10px}}{{7seg|u|10px}}{{7seg|n|10px}}, {{7seg|F|10px}}{{7seg|A|10px}}{{7seg|I|10px|bc}}{{7seg|L|10px}}, {{7seg|E|10px}}{{7seg|r|10px}}{{7seg|r|10px}}{{7seg|o|10px}}{{7seg|r|10px}}, {{7seg|S|10px}}{{7seg|E|10px}}{{7seg|t|10px}}{{7seg|U|10px}}{{7seg|P|10px}}, {{7seg|H|10px}}{{7seg|E|10px}}{{7seg|L|10px}}{{7seg|P|10px}}
 
:{{7seg|M|10px|abef}}{{7seg|M|10px|abcf}}{{7seg|o|10px}}{{7seg|d|10px}}{{7seg|E|10px}}, {{7seg|o|10px}}{{7seg|n|10px}}, {{7seg|O|10px}}{{7seg|F|10px}}{{7seg|F|10px}}, {{7seg|y|10px}}{{7seg|E|10px}}{{7seg|S|10px}}, {{7seg|n|10px}}{{7seg|o|10px}}, {{7seg|H|10px}}{{7seg|o|10px}}{{7seg|t|10px}}, {{7seg|C|10px}}{{7seg|o|10px}}{{7seg|L|10px}}{{7seg|d|10px}}
 
==See also==
[[File:Common segment displays.svg|right|thumb|7-, [[nine-segment display|9]]-, [[fourteen-segment display|14]]-, and [[sixteen-segment display|16]]-segment displays shown side by side]]
{{commons|Seven segment display}}
There are also fourteen- and sixteen-segment displays (for full [[wikt:alphanumeric|alphanumeric]]s); however, these have mostly been replaced by [[Dot-matrix display|dot matrix displays]]. 22-segment displays capable of displaying the full [[ASCII]] character set<ref>{{cite web |title=DL-3422 4-digit 22-segment alphanumeric Intelligent Display preliminary data sheet |website=Internet Archive |publisher=Litronix 1982 Optoelectronics Catalog |page=82 |url=https://archive.org/stream/bitsavers_litronixdaOptoelectronicsCatalog_31011858/1982_Litronix_Optoelectronics_Catalog#page/n81/mode/2up |access-date=2016-09-03}}</ref> were briefly available in the early 1980s but did not prove popular.
*[[Fourteen-segment display]]
*[[Sixteen-segment display]]
*[[Dot matrix display]]
 
* [[Eight-segment display]]
[[Category:Display technology]]
* [[Nine-segment display]]
* [[Fourteen-segment display]]
* [[Sixteen-segment display]]
* [[Dot matrix display]]
* [[Nixie tube]] display
* [[Vacuum fluorescent display]]
 
==References==
[[de:Segmentanzeige]]
{{Reflist|refs=
[[es:Visualizador de siete segmentos]]
<ref name="elektor-UK_1981-72">{{cite magazine |title=junior cookbook: a few healthy recipes to keep your computer in shape |author-first1=H. P. |author-last1=Diehl |author-first2=H. D. |author-last2=De Mulder |date=April 1981 |volume=1981 |issue=72 |magazine=[[elektor]] (UK) – up-to-date electronics for lab and leisure |language=en |pages=4-28 – 4-31 [4-30 Figure 4] |url=https://worldradiohistory.com/UK/Elektor/80s/Elektor-1981-04.pdf |access-date=2020-07-03 |url-status=live |archive-url=https://web.archive.org/web/20200703164044/https://worldradiohistory.com/UK/Elektor/80s/Elektor-1981-04.pdf |archive-date=2020-07-03}}</ref>
[[fr:Afficheur 7 segments]]
}}
[[ko:7세그먼트 표시 장치]]
 
[[it:Display a sette segmenti]]
==External links==
[[nl:Zevensegmentendisplay]]
{{Commons|Seven segment display}}
[[ja:7セグメントディスプレイ]]
* [http://www.uize.com/examples/seven-segment-display.html Interactive Demonstration of a Seven Segment Display]
[[pl:Wyświetlacz siedmiosegmentowy]]
* [https://www.dnatechindia.com/Tutorial/8051-Tutorial/Interfacing-7-Seg-Display-to-Microcontroller.html Interfacing Seven Segment Display to 8051 Microcontroller]
[[ru:Семисегментный индикатор]]
* [https://circuitdigest.com/microcontroller-projects/0-99-counter-using-avr-atmega32 Interfacing 7-Segment Display with AVR Microcontroller]
[[tr:Gösterge (Display)]]
 
[[zh:七劃管]]
{{Display technology}}
 
[[Category:Display technology]]