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Solid State Displays

By the beginning of the 1970s, LED indicators started to evolve into LED displays. The earliest LED displays are constructed of dozens of small indicator-style dies, while later displays are constructed from more complicated multi-segment dies. Simple displays were eventually supplanted by LED intelligent displays, the first class of true computation/display components to come about since the Dekatron and other direct-view counting tubes were introduced in the 1940s and 1950s.

The beginning of the 1970s also saw the introduction of liquid crystal technology, which would ultimately displace LED displays in many applications.

Hewlett-Packard 5082-74xx Series

Devices included in this entry: Hewlett-Packard 5082-7433 (12-pin 3 digit red epoxy DIP; pictured in thumbnail) Hewlett-Packard 5082-7415 (14-pin 5 digit red epoxy DIP) Hewlett-Packard 5082-7412 (12-pin 3 digit red epoxy DIP) Hewlett-Packard 5082-7432 (12-pin 2 digit red epoxy DIP) Hewlett-Packard manufactured a number of early DIP single die LED displays for use in handheld calculators, designed to be mounted in larger linear arrays. The HP 5082-7433 is a three-digit, seven-segment red LED display, which is is compatible with the Litronix DL3xx series shown below, as well as other similar displays. The -7433 is not intelligent; control must be furnished entirely with external driver circuitry. The 5082-7415 is the five digit version of the -7433, and is otherwise electrically similar. The 5082-7432 is a strange two-digit version of the 7433, enclosed in a truncated 3-digit epoxy package wih only two of the digits have dies installed. The -7412 is a similar device - a 12 pin, four digit package with only the three rightmost digits populated with dies. [View Detail]

Hewlett-Packard 5082-73xx Series

Devices included in this entry: Hewlett-Packard 5082-7340 red intelligent LED display (8-pin red epoxy DIP) Hewlett-Packard 5082-7359 red intelligent LED display (8-pin glass-on-ceramic DIP) Hewlett-Packard HDSP-0962 green intelligent LED display (8-pin glass-on-ceramic DIP; pictured in thumbnail) The 5082-73xx series is the Caddilac of early single-digit intelligent LED displays: onboard hexadecimal decoder with positive 8-4-2-1 logic inputs, display blanking and onboard memory, all in a tiny 8-pin DIP, significantly smaller than the benchmark TIL311. The -73xx series of intelligent displays have a false bitmapped display, which gives the appearance of a true bitmapped character, but only includes the pixel elements required to make up the display's limited character set (0-9, 0-F, or +1 depending on the part number). Unlike true bitmapped character displays, which usually have a 5x7 matrix, the -73xx series devices have a 4x7 matrix, with the elements spaced further apart horizontally than vertically. 5082-7300 Series Datasheet [View Detail]

Hewlett-Packard 63030123
	16-digit LED calculator display with enlargement lenses. Early multi-digit displays like this one used a single die for each digit, and an external epoxy magnifier was mandatory for readability. This display is new, not salvaged from a calculator. [View Detail]

Hewlett-Packard 2416 & 1414 Series

Devices included in this entry: Litronix DL1414T (plastic DIP) Litronix DL2416T (plastic DIP; pictured in thumbnail) Hewlett-Packard HPDL-2416 (plastic DIP) More than a mere display, the HPDL-2416 is an entire seven-bit ASCII decoder, character generator, and four-digit alphanumeric display in a single package. The display is made up of four 17-segment dies mounted under a plastic magnifier, with the control circuitry mounted to the underside of the display and covered with an epoxy coating. The display has its own memory registers, and will remember character data without processor intervention. The 1414 (HPDL-1414, DL1414T) is a smaller, less capable version of the 2416 alphanumeric display. The 1414 lacks the cursor generation and display blanking of the 2416, but the omission of the pins for those functions results in a display that is both smaller and easier to drive than a 2416. Siemens DL1414 Datasheet (PDF, 365kb) [View Detail]

Siemens DLR2416

The DLR2416, manufactured by Siemens, is a pin-compatible drop-in replacement for the DL2416 and HPDL 2416 intelligent displays shown above. Though the DLR2416 has all of the decoding and memory capabilities of the DL2416, it replaces the more basic 17 segment single die emitters of the DL2416 with crisp 5x7 matrices constructed of individual dies. This enhanced display allows for the DLR2416's internal character decoder to generate a substantially extended set of characters, including lowercase, accented, and umlaut letters not available in a standard 2416. [View Detail]

Siemens MDL2416

Most smart displays are designed to survive in a harsh world filled with filthy humans, but the MDL2416, made by Siemens, is overbuilt to ridiculous levels only needed to withstand the wrath of Enemies of the State. The MDL2416 is a military version of the venerable DL2416 smart display shown above, and is different from it's comparatively pedestrian relative in nearly every way outside of pin assignments. The MDL2416 is packaged in a very thick metal case with a hermetically sealed glass cavity lid. The individual LED dies are mounted to a ceramic substrate with gold leads, and the pins exit the display through glass frits to complete the seal. Electrically, the MDL2416 functions identically to the civilian 2416; the ASCII decoder and drivers are present and have been attached to the underside of the ceramic substrate in a special cavity provided for such. The MDL2416 may not be able to survive global thermonuclear war, but it has a much better chance of surviving the inside of an engineers pocket than lesser epoxy-clad displays. [View Detail]

Hewlett Packard 5082-7107

The 5082-7107 is a large, high quality red LED bitmapped display, manufactured by Hewlett Packard. The display contains a five digit array of discrete LED dies and has no internal logic or controller; rows and columns must be manually selected and multiplexed to display a character. This display is extremely ruggedized - the white ceramic package, glass cavity lid, and all gold construction make it an impressive example of military-grade LED display construction. [View Detail]

Hewlett-Packard HDSP-2xxx Series

Devices included in this entry: Hewlett-Packard HDSP-2010 red intelligent LED display (12-pin red glass-on-ceramic DIP) Hewlett-Packard HDSP-2030 red intelligent LED display (12-pin red glass-on-ceramic DIP) Hewlett-Packard QDSP-2273 yellow intelligent LED display (12-pin glass-on-ceramic DIP; pictured in thumbnail) Hewlett-Packard HDSP-2003 green intelligent LED display (12-pin glass-on-ceramic DIP) Hewlett-Packard QDSP-2021 red intelligent display (12-pin glass-on-ceramic DIP) Hewlett Packard's HDSP-20XX is an intermediate device, a functional step between purely 'dumb' character displays like the Monsanto MAN-2A and full-featured smart displays like the DL-1414. All control schemes for large strings of 5x7 LED matrix arrays rely on heavy use of shift registers to store the bit patterns being displayed on the device; the 20XX takes the step of moving those shift registers into the display itself. There is no internal character driver or latch on this display, the controlling system must laboriously shift bitmap data into the display, 28 bits at a time. Like columns across each digit are tied together and row data from each column is shifted to adjacent digits instead of adjacent columns, all this results in an exceptionally tedious display to control. Like most high end HP displays, the 2xxx series was manufactured in a range of LED colors. It should be noted that the HDSP-2010 and -2030 are among the few displays ever made to use a red glass and ceramic package. Similar displays of this era are manufactured with either clear glass or much cheaper red epoxy. [View Detail]

Hewlett-Packard HDSP-211x Series

Devices included in this entry: Hewlett-Packard HDSP-2111 intelligent LED display (28-pin composite DIP) Hewlett-Packard HDSP-2112 intelligent LED display (28-pin composite DIP; pictured in thumbnail) The Hewlett-Packard HDSP-211x is a family of eight-digit, 5x7 bitmapped character LED intelligent displays with full 7-bit ASCII, 16 user-definable characters, daisy-chainable master clock, internal oscillator option, multilevel dimming and blanking, and full read/write operations. HDSP-211x Series Datasheet [View Detail]

Hewlett-Packard HCMS-3966

The HCMS-3966 is a step along the trend in the evolution of LED smart displays, designed for a world of programmable microcontrollers where no factor holds more weight than reducing the number of I/O pins needed to control a device. The HCMS-3966 is a 3.3 volt compatible serial display that works much like the earlier HDSP-2xxx devices, in that it has no character driver and data is directly shifted into registers that represent the LED's in the 5x7 display matrix. Unlike the tedious to control HDSP-2xxx devices, the registers in the 3966 shift bits in a logical manner from right to left, making it much easier to shift data into the device. Unfortunately the 3966 is a much less TTL friendly device than the HDSP-2xxx; a built in brightness register is set to zero by default, and can only be changed by clocking in the correct serial data word into the appropriate control register. This is one device that can not be clocked and tested manually with pushbuttons. HCMS-3966 Series Datasheet [View Detail]

Fairchild FND-10

Fairchild's FND-10 is a small numerical display that uses a single LED die for all seven segments, similar to multi-digit displays like the NSA578. This display is extremely tiny: the width of the package is only 6mm. The FND-10 has eight pins arranged in a miniature DIP configuration with a ninth pin located in the center of the displays underside. Company literature claims that this display could be easily read from five feet away, but given the digit's tiny size and 650 microcandle light output, such claims seem wildly optimistic. [View Detail]

General Electric SSL-140

One of General Electric's most well-known displays, the SSL-140 is an early seven-segment LED in a tiny surface mount package. The SSL-140 is a single die device, in that all of the segments are constructed on the same lump of silicon. The display's decimal point is a separate small cubical die located in the right side of the display area. The SSL-140's dies are bonded to a ceramic wafer with gold leads, with an enclosing plastic cover to protect the fragile dies and bond wires. [View Detail]

Litronix DL3xx Series

Devices included in this entry: Litronix DL330 (epoxy 12 pin DIP) Siemens DL340M (plastic 14 pin DIP; pictured in thumbnail) The Litronix DL3xx series of parts is a fairly typical example of early multi-digit seven segment display technology. The DL3xx series is constructed of single-die digits - all seven segments are etched into a single die. In an effort to make these single die devices more legible, large magnifier lenses were incorporated into the epoxy package. Litronix parts are fairly rugged, but have notoriously lousy build quality; thick tinned traces, sloppily placed dies, and hand-written lot numbers are all hallmarks of a Litronix product. Litronix DL3xx series parts were second sourced by Siemens; the DL340 pictured in the thumbnail is actually the Siemens variant of the part. The Siemens manufactured parts are significantly higher quality than the Litronix units they are designed to emulate, the DL340 shown above has heavy gold traces and a substantially different package with smaller, more precisely cast magnifier lenses. [View Detail]

Litronix Two-Digit Display (Unknown P/N)

Litronix, though well-known for their second source clones of displays like the DL1414, made many original parts as well. Original Litronix parts are notoriously hard to identify since they typically lack part numbers, and have only handwritten lot numbers. This is a typical example; we have no idea what the part number of this device might be, but its construction is typical of Litronix devices. The display's tiny single-die LED elements are made visible by ludicrously over-sized, anatomically suggestive magnification lenses. [View Detail]

Monsanto MAN-1 Series

Devices included in this entry: Monsanto MAN1 (14-pin clear epoxy DIP; pictured in thumbnail) Litronix MAN1 (14-pin clear epoxy DIP) Monsanto MAN1A (14-pin red epoxy DIP) The MAN-1 is generally considered to be the world's first production seven-segment LED display. Following the introduction of the MAN1, the now-familiar seven-segment LED rapidly took over the world, wiping out the demand for Nixie tubes, Minitrons, Panaplex displays, and many other display technologies in a single blow. Each segment of the MAN-1 is made up of two silicon wafers, which each contain four diode elements. With the inclusion of a decimal point, the entire display contains 57 separate light emitting sectors, which is quite a lot compared to modern displays which typically only use a single diode for each segment, or even a single etched die for each character. The MAN-1's first-generation diode technology results in a very dim display, but the virtual immortality of LED technology was a drastic improvement over the incandescent Minitron displays and complex gas-filled devices it was designed to compete with. Soon after the release of the MAN-1, Monsanto introduced a modified version, the MAN-1A. The MAN-1A is identical in functionality and basic construction to a standard MAN-1, but has a dark red epoxy case which does a great deal to hide the display's ugly internal construction. [View Detail]

MAN-2A (Unknown Mfr.)

The MAN-2 is considered by most to be the first bitmapped 5x7 pixel LED display. A key product in Monsanto's line of ground-breaking LED numerical displays, the MAN-2's bitmapped display area could display letters and characters that were beyond the graphical capabilities of the seven-segment MAN-1. Unlike the TIL311 and other bitmapped smart displays that would follow, the MAN-2 contains no driver circuitry. External character generator logic is required to drive the display's many pixels. The MAN-2A shown in the photo is of unknown manufacture, but we believe it is most likely made by General Instrument based on a microscopic examination of die construction. Authentic Monsanto MAN-2's can be easily identified by the large engraved 'M' logo in the epoxy above the digit. [View Detail]

Monsanto MAN-3 Series

Devices included in this entry: Monsanto MAN-3 (10-pin clear epoxy flat-pack; pictured in thumbnail) Litronix MAN-3A (10-pin red epoxy quad inline package) Monsanto MAN-3A (10-pin red epoxy quad inline package) The MAN-3 is generally considered to be the first surface mount seven segment display ever made. This display is tiny: digit height is only 3mm and package dimensions are 6mm by 4mm. The unit has ten gold plated pins for mounting, and the two center pins are shared grounds. The MAN-3A is a more refined version of the MAN-3 which has a red epoxy case instead of a clear one. Here is a picture of the packaging for these displays, showing how they would have arrived from the factory. Sorry, there's no enlargement for the fantastic thumbnail - we had a bit of difficulty photographing the MAN-3, and that's the best, largest shot we could manage. [View Detail]

Monsanto MAN-4

The somewhat unusual looking MAN4 LED display was Monsanto's attempt to add a low cost option to its line of first generation LED products. Instead of being contained in a custom epoxy package, the MAN-4 is encapsulated in a standard 14-pin plastic DIP, made from red resin for visibility. This results in a hilariously small display area relative to the size of the package - the LED digit within the MAN-4 is only 4mm high. Each segment of the display is made from a single elongated LED die, bonded to a common sheet metal leadframe. The MAN-4 was a rather unpopular product, and was used in relatively few devices. [View Detail]

Monsanto MAN6A / MAN601A

Devices included in this entry: Monsanto MAN-6A (14-pin red epoxy offset DIP; pictured in thumbnail) Monsanto MAN-601A (14-pin red epoxy offset DIP) The MAN6A is Monsanto's first attempt at marketing a LED display with a larger digit size than their earlier DIP LED displays like the MAN1A. The MAN6 utilizes the same LED dies as a MAN1, but each segment is constructed out of four dies instead of two, which doubles the displayed digit size. Even though the MAN6A is packaged in an unusual square package, it retains the same pinout and base configuration as a MAN1; one row of pins has been offset to allow the larger package to be inserted into a standard 14-pin DIP socket. The multitude of extra dies in the MAN6A made it a costly device to produce, which resulted in the displays seeing little commercial application. Monsanto also made a jumbo-sized overflow indicator to go with the MAN6A, the MAN601A. As hilarious as it may sound, the MAN601A uses the exact same number of dies as a MAN-1 series overflow indicator, the dies have simply been spread out with large gaps in order to make the size of the displayed digit match the MAN6A. The MAN601A easily ranks as one of the ugliest overflow indicators ever constructed by humanity. [View Detail]

Litronix Single Digit LED Display with Magnifier (Unknown P/N.)

This unidentified Litronx display appears to be a direct competitor to the Monsanto MAN-4; it has the same pinouts and utilizes a similar reduced-die construction. To counteract the laughably small digit size resulting from the use of single bar elements for each digit, Litronix has equipped this display with a large built in magnifier that dominates the front of the package. Each LED bar element has four circular active areas arranged along its length, which gives the display its bitmapped appearance. The ball bond wires are attached to each die via oblong pads located between the active LED areas. We have been unable to fully identify this part, but suspect it must date from very early in the history of LED production based on an extremely crude construction quality that leaves one wondering if these displays were made under duress in some sort of imaginary LED gulag. [View Detail]

Soviet Surface Mount LED (Unknown P/N)

Most Western manufacturers abandoned the multiple die style construction of the Monsanto MAN-3 before a viable green LED chemistry was developed; nearly every LED calculator in the world uses red LED displays. The Soviets were one of the few groups still manufacturing single die 7-segment LED's at the time green LEDs were commercialized, and as such this Soviet-era MAN-3 clone is a strange beast, a green LED constructed in classic vintage single die style. The display is very nearly the same size and shape as a Monsanto MAN-3 and contains seven elongated dies for the segments and an eighth square die for the decimal point. The dies are not divided into multiple active 'dots' as in other displays of this construction style, the entire surface of the die emits light. The LED package is almost perfectly clear and the ground plate is cut to match the shape of the segments, which gives these displays a striking transparent appearance not shared by other vintage LEDs. [View Detail]

Surface Mount LED Display with Magnifier Lens (Unknown Mfr.)

This unusual device is a tiny surface mount LED display with a twist; a built in magnifier. This device can display normal seven-segment characters and has a decimal point indicator, but lacks the second ground contact common to other displays of this general form. The leads on this example are clipped, but it is likely that the display originally had quad inline leadforming based on the way the contacts have been clipped. Digit height on this display is only 1.5mm and the tiny, vaguely comical built in magnifier lens does little to improve the size of the displayed digit. We have no idea who manufactured this strange LED, but suspect from the construction style that it was probably made by Litronix. [View Detail]

RFT VQC10

In spite of prevailing evidence, not all LED smart displays were made by Hewlett Packard. RFT, based in Germany, also made smart displays such as this one, the VQC10. Packaged in an attractive red molded epoxy package, the VQC10 has four characters, each containing 35 LED dies arranged in a 5x7 matrix. Unlike many other smart displays, the VQC10 has no built in character driver or other advanced features. The display uses an extremely convoluted control scheme, rows across all digits are ganged together and controlled manually, while each column can be selected by sending a 9 bit address in parallel to the display's driver circuitry. The home experimenter should take note that the VQC10 has wider pin spacing than most DIP LED displays, and will not fit in a conventional breadboard or socket. VQC10 (VQC 10) Datasheet (PDF, 133kb) [View Detail]

National Semiconductor NSA578

The NSA578 is an example of the next step in display evolution after single digit displays like the MAN-1, as it incorporates all seven segments into a single die. Such displays were popular for early pocket calculators and watches, where the small size of the numerals did not cause a hindrance to operation. The NSA578 contains seven digits, each whole digit is etched on a single die, and soldered to a standard PCB backing. The dies' leads are connected to tracks on the PCB by fine wires, similar to the die connections used in most semiconductor chips. The display's decimal points are separate dies, each with their own PCB pad and connecting wire. Due to the small size of single-die digits, most such assemblies used an external magnifier to make the digits more readable. The NSA758 is unusual in that it does not have an external magnifier. Instead, a red plastic cover is the only barrier between the dies and the outside world. Here is an image of the display with the cover removed, which reveals the single-die digits. [View Detail]

MAN2185 / DL2185 Series

Devices included in this entry: Litronix DL2185 intelligent LED display (23-pin composite DIP) Monsanto MAN2185 LED display (23-pin composite DIP; pictured in thumbnail) The MAN2185 display is a multidigit alphanumeric display manufactured by Monsanto. Like many other early displays that contain multiple digits, each digit of the 2185 is made of a single die of wafer material, as opposed to being assembled of individual dots or strips of LED material like the MAN-1. Despite appearances the MAN2185 does not actually have full 17 segment characters, both center segments are ganged together to reduce the amount of wiring needed for each die. Unlike many other displays of this type, 2185 is a manually controlled device, with no onboard character ROM or driver circuitry. Litronix manufactured a second-source version of this part, the DL2185. The DL2185 is nearly identical to the MAN2185, but replaces the linear magnifier of the Monsanto display with discrete bubble magnifiers for each digit. [View Detail]

RCA TA-8032

The TA-8032 is a pre-production laboratory sample of the (then brand new) RCA liquid crystal technology, which would eventually take over the world in everything from wristwatches to televisions. This display was made in October of 1970, and predates the release of the first LCD products by several months. In effect, this is one of the first complete LCDs ever made, and it is very different from a modern liquid crystal display in both package and function. The most noticeable feature of first generation LCD technology is the inverted display; unlike a modern LCD which displays a black digit on a white background, early LCDs display white digits and must be mounted to a dark background to be legible. The glass envelope on the TA-8032 is so bulky compared to the size of the displayed digit that it borders on the ridiculous, RCA would have never released a display in such an impractical package for use in commercial products. The two metal posts on the front of the display may appear as though they are intended to hold the two halves together, but they actually cover the fill and vent tubation that would have been used during manufacture to pump the liquid crystal material into the display. It should be noted that LCDs which used this early technology were very failure prone, and few have survived to the present day. The first practical LCD display did not arrive until 1973 when Sharp first released calculators based on its new and more reliable COS LCD technology. [View Detail]

Hewlett Packard 5082-7000

Hewlett Packard's 5082-7000, manufactured in 1969, is believed to be the first smart LED display to ever be commercially produced. This device probably ranks as one of the most archaic LED displays we have ever seen: a smart display in a hermetic metal package. The digits in this device are somewhat stylized--each is equipped with an extra row of LED dies to allow for the generation of more natural representations of the '4' digit. Very few displays offer this feature, as it significantly increases the number of dies necessary to display a digit. The display includes a built in BCD decoder, which is located above the displayed digit. The leads of this device are attached to the metal can enclosure with glass beads and an internal ceramic substrate acts as a base for the display's internal gold traces. This display was made in both white and gray ceramic versions, the white version is shown here. Note the large metal heatsink mounted under the display, which dissipates the substantial amount of heat this device generates. The 5082-7000 saw use in a historically significant device, Hamilton's 'Pulsar' first generation LED watch. In order for the bulky 7000 series displays to be fit into the watches' casing, Hamilton had special reduced-size ceramic billets constructed by a 3rd party company, which were then sent to HP for installation of the LED dies and proprietary controller ICs. [View Detail]

Hewlett Packard 5082-7001

This is a three digit analog of the single digit Hewlett Packard 5082-7000 smart display shown above. As with the device above, this display is enclosed in a hermetic metal can package and contains an extra set of LED dies for use in the display of the '4' character. The most unusual aspect of this device is the use of a separate BCD driver IC for each digit; nearly every multi-digit smart LED display uses a single chip to drive all of the digits, to save on silicon. Each digit is also installed on a separate purple ceramic wafer. The choice of a metal enclosure is not purely a cosmetic one; this device pulls nearly 400ma of current while in operation, and the heat generated is not insignificant. The aluminum heatsink shown in the photo is not an optional accessory, but necessary to keep the device from being consumed by its own thermal waste. The 1971 Hewlett Packard price guide lists a single quantity value for this display of $165, making it one of the most expensive LED displays of its time. [View Detail]

Texas Instruments TIA8447

The TIA8447 is a nearly modern incarnation of Texas Instruments' backbone TIL302 seven segment display. The TIA8447 features a ruggedized package with a hermetically sealed glass-and-ceramic carrier and gold leads. The unit is a 'dumb' display; it contains no driver circuitry and all such functions must be supplied with external logic. The TIA8447 has identical pinouts to the TIL302, making it a drop-in replacement. [View Detail]

Texas Instruments TIL306

The Texas Instruments TIL306 is an intelligent single-digit LED display featuring a built-in decade counter and BCD output. The example pictured here is a Dialco-branded variation, yet the TI logo is clearly visible through the epoxy. The inclusion of a decade counter within an LED display quickly proved to be a failure in the marketplace, and TI and other companies largely abandoned their pursuit of such products to focus their energies on BCD and ASCII based displays. [View Detail]

Texas Instruments TIL308

Though the Texas Instruments TIL308 appears externally identical to TIL306 shown above, internally it is quite different. The TIL308 lacks a built in decade counter, instead it accepts BCD hexidecimal data directly, a much more flexible arrangement. The TIL308 family was in fact both the forerunner and quickly superseded by the smaller and much more popular TIL311 BCD display shown below, and as such was limited to a relatively short product lifespan. Special thanks to Dr. Bruce Jarnot for donating this rare display. [View Detail]

Texas Instruments TIL311

The Texas Instruments TIL311 is the definitive example of hexadecimal smart display technology. Used in innumerable electronic systems over the years, the TIL311 contains a BCD decoder and a hexadecimal character set in addition to its LED elements. The TIL311 is larger than HP's competing 7300 series of displays, but can still be inserted into a standard DIP socket. The TIL311 is so popular that they are still manufactured to the current day, and see use in a number of short-run industrial control systems and test fixtures. [View Detail]

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