Monolithic Integrated Circuits

Click photos to enlarge.


Texas Instruments SN514

TI's SN51x series of RCTL logic chips, released in 1961, is widely recognized to be the world's first commercially available line of integrated circuits. 'SN' stands for 'Semiconductor Network', TI's nod towards the then-radical idea of combining multiple solid state devices into a single package. The SN51x series chips were manufactured from multiple transistor and diode dies, which were hand-wired together with thread-like interconnect leads inside the package. Constructing chips in this manner was both labor-intensive and expensive: early SN51x series chips sold for over $400 when first released.

These early ICs were primarily targeted towards the military and aerospace industry, and the SN514 (along with the SN510) were the first integrated circuits to orbit the earth. The earliest SN51x series chips were packaged in gold plated flat-packs. This example, a SN514 NOR/NAND gate made in November 1962, abandons the military gold package in favor of a more primitive looking 'block of carbon'-style enclosure.


Texas Instruments SN514 Integrated Circuit
OKI Intel M85C154

The Intel M85C154 is a special class of microprocessor known as a 'piggyback' CPU. Piggyback microprocessors are designed to act as a programming development tool and can be easily recognized by the presence of a top mounted socket. In use, the engineer would program a blank EPROM on a desktop computer with their test code, then insert the EPROM into the socket on the microprocessor so the code loaded inside could be tested. Once the code was tested and finalized, a cheaper one-time-programmable microprocessor with built in EPROM would be used in the final product.

The M85C154, an 8 bit CPU based on the Intel 8051, is fairly representative of a typical piggyback microcontroller. This device has a maximum clock speed of 22MHz and 16k of onboard ROM space. Additionally, the M85C154 can address up to 64K of program ROM through it's piggyback socket.

OKI Intel M85C154 Datasheet (PDF)


OKI Intel M85C154 Piggyback Microcontroller
Cypress CYM1620

The CYM620 is a 1 megabit static ram module built around several leadless ICs mounted to a ceramic carrier. Four of these chips are 256k static RAMs, with the fifth being a decoder IC. The RAM units are grouped into a high and low pair, with the decoder reading the highest position address bit to determine which pair should be active. The TTL level inputs and outputs as well as the substantial hermetic packaging and wide temperature ratings make this a fairly robust memory IC.

The example shown here is the -55C variant, which is rated for commercial use and has an access time of 55 nanoseconds.

Cypress Semiconductor CYM1620 Datasheet (PDF)


Cypress CYM1620 Static Ram
Amdahl 470A

The Amdahl 470A is an unusual LSI CPU component chip that was used in Amdahl's 5860 "supercomputer" mainframe. Amdahl was known for making air-cooled computers in a market dominated by water cooling, which resulted in their chips having a very unique construction. This chip is no exception, the top is dominated by a tall heatsink that would have poked into a forced air cooling channel when installed in a computer. During use, many such chips would be bonded into large arrays to construct a complete CPU. Note that this chip has a Fujitsu makers mark... Fujitsu was Amdahl's largest shareholder and eventually grew to own the company outright.

Amdahl's CPUs were so unique in appearance that many factory defects found their way into Lucite promotional paperweights that were produced by the company as sales samples and awards. This is the predominant form in which they are seen nowadays, as Amdahal's various air cooled chips never saw wide use outside the company.


Amdahl 470A LSI IC
Amdahl 209

Even in a world filled with bizzare Amdahal integrated circuits, the Amdahl 209 stands apart. The 209 is an LSI RAM IC in a complicated multi-chip package that was used in the Amdahl 5860 mainframe. This strange looking device is equipped with four distinctive aluminum cooling towers that are bonded to the chip with black epoxy. Each cooling tower is attached to a small square leadless IC, which is in turn bonded to a ceramic carrier. The leadless ICs are actually mounted to the carrier upside down... each has a gold cavity lid pressed tightly against the ceramic of the attached carrier. The four gold pads on the top of the 209 are actually heat spreaders, which connect directly to the underside of the four dies in each package.

Sadly the 209, like most Amdahl chips, has completely undocumented specifications. It is unlikely that these chips will ever see significant use in home-brew electronics projects, due to a lack of reliable connection data.


Amdahl 209 LSI RAM (76800 209)
AMI C1761

Not much is known about this mysterious MOS integrated circuit, other than that it was made by American Micro Systems and has a rather unique package style. The C1761 is packaged is a highly unusual 40 pin white ceramic leadless carrier with a round cavity lid. Earlier versions of this chip make use of a single layer gray trace leadless wafer, though sometime around 1973 AMI switched to a two-piece package which covered the traces in a second layer of ceramic. On the revised package the start and end pin numbers are conveniently printed on the side of the ceramic, and the base is keyed in such a way that prevents the chip from being inserted into it's socket backwards, a feature well ahead of it's time in 1973. We don't currently know the function of this IC, but it is likely a calculator chip or part of a calculator chipset given the manufacturer and package style. Strangely, the device has no insertion marks on the pins and was found in its original packaging, suggesting it was sold in the retail market.


AMI C1761 Integrated Circuit
Intel 1301

The 1301, first released in 1969, is Intel's first mask rom, and is a compatible replacement for the groundbreaking 1701 UV erasable PROM. The 1301 is programmed at the factory with a metal mask, and was marketed as a low cost alternative to the 1701 for mass-produced items where it was not necessary for the chip to be erasable. The 1301 has a storage capacity of 256 bytes, or 2048 bits, and is also equipped with TTL compatible outputs. The example shown here is an earlier gray trace version, and has a date code from 1972.


Intel 1301 Integrated Circuit (Mask ROM)
Intel 1601

The Intel 1601 is a 256 byte PROM that was designed to be drop-in compatible with Intel's 1301 metal mask ROM. A 1601 PROM has a significant advantage over the 1301; in that it can be programmed electronically by the end user without the need for factory-applied masks. Released in 1970, the earliest versions of this chip have opaque gold lids and gray trace ceramic packages. Later versions were simply 1701 UV erasable EPROMS with black vinyl covering up the UV erase window. Unfortunately the black vinyl cover, which has the part number printed on it, has long since fallen away on this example. With the cover removed late model 1601's are basically indistinguishable from an Intel 1701; it is likely that at least a few unidentified 1601s are sitting in chip collections around the world.


Intel 1601 Integrated Circuit (PROM)
IDT 7M912

The 7M912, manufactured by Integrated Device Technology, is a 64k 9 bit CMOS static ram module constructed out of leadless SRAM chips bonded to a multi-layer ceramic substrate. THe 7M912 is built from nine separate IDT7197 SRAM integrated circuits, five of which are attached to the top surface of a ceramic carrier with the remainder being mounted to the underside. This integrated circuit is military rated, and is designed for use in harsh environments and high demand applications. The 40 pin package has been manufactured with extra-long leads, to prevent socket insertion from fouling the chips on the underside of the package.

IDT also made an 8 bit version of this chip, the 7M812. The 7M812 is identical in function to the 7M912, but only utilizes 8 IDT7197 SRAM ICs.


IDT 7M912 9 Bit Static Ram IC
Toshiba TMM121

This strange looking chip is Toshiba's first EPROM device, the TMM121 UV-erase EPROM. Intended to be a competitor to Intel's 1701 UV EPROM, the TMM121 can store 256 bytes in stable UV-erase memory. The chip has an extremely unusual flanged round lid with a central window, which allows the die inside to be exposed to UV light when erasing is desired. The die is housed in a white ceramic carrier with bottom-brazed pins and a large locating notch. The TMM121 was used in Toshiba's first microcomputer, the TLCS-12A, which is an unusual 12 bit system originally designed for use in automotive applications. We do not know the date of manufacture for this device, but it was likely released sometime around 1973.


Toshiba TMM121 EPROM Integrated Circuit Chip
National Semiconductor MM5203

The National Semiconductor MM5203 is a 2048 bit UV erase PROM that was in production for a number of years. The earliest versions of this chip are mounted in a white ceramic carrier with gold leads and a square cavity window. Later versions switched to a gray ceramic package, but retained the square cavity window and gold leads. The most modern and boring versions of this chip are mounted in a standard ceramic package with a round erase window and tinned leads. In normal operation the window is covered with a label or sticker, to prevent ambient UV light from slowly destroying the data stored on the PROM.


National Semiconductor MM5203 EPROM Integrated Circuit
Ferranti ULA 9RK020

The Ferranti 9RK020-3F programmable gate array is a poorly documented device. Not much is known about this chip, other than it is part of Ferranti's line of ULA 'Uncommitted Logic Array' integrated circuits. Ferranti ULA chips saw use in a number of noteworthy computer products from the 1980s, including the Timex Sinclair ZX81 and ZX Spectrum. The 9RK020 is probably most closely related to the 12C021M, a 12 tile programmable array used in the Acorn Electron home computer. The manufacturers of the Acorn Electron relocated nearly all of the computer's support logic into a 12C021M array, resulting in a 90 percent reduction of the Electron's total chip count. The complexity of this ULA caused significant disruption to the Electron's 1983 launch however, resulting in delays and manufacturing shortages as Ferranti struggled to ramp up production of the complicated device.

The Ferranti 9RK020-3F is packaged in a ceramic leadless carrier similar in size and shape to the ULA used in the Acorn Electron. The 9RK020-3F is not leadless however; long gold pins have been brazed to the pads on the carrier, converting it into a surface mount flatpack. We suspect the 9RK020 is a 9 tile device, but it's specifications are otherwise unknown.


Ferranti ULA 9RK020 Uncommitted Logic Array IC
Burroughs LSIC B Series Gate Array

These largely undocumented parts, produced by AMI, Fairchild, and Burroughs, are LSIC gate arrays used almost exclusively in Burroughs B series minicomputer systems. Burroughs B series computers were bulky console-style machines which were typically built into a desk or table with a large line printer as the only form of display. The AMI 1845-9909, shown in the thumbnail, is believed to be a 150 element gate array originally manufactured for use in a Burroughs B80. Nine of these gate arrays would be combined to form the complete 8 bit central processing unit of the B80. Unfortunately the exact specifications of these chips is unknown; no datasheets or part lists appear to have been released by Burroughs, and the homebrew electronics community has made little progress in unlocking their secrets. Despite this, Burroughs processor chips see a decent amount of turnover amongst chip collectors, due almost entirely to their strange form factor. Burroughs gate arrays are packaged in large white ceramic pin grid carriers with gold traces and a central round cavity lid, and have a distinct appearance unlike any other integrated circuit. Electronics lore has that the original Burroughs service technicians referred to these devices as 'fried egg chips' due to their unusual packaging. The example shown in the thumbnail was manufactured in 1976.


Burroughs LSIC B Series Gate Array (AMI 1845 9909)
Intersil 6100

The Intersil 6100 is a 12 bit CMOS microprocessor first produced by Intersil in 1975. This relatively popular microprocessor family was manufactured in white, purple and plastic versions by both Intersil and Harris Semiconductor. The 6100 used the same instruction set as the popular PDP-8 series of minicomputers, and as a result was used in a number of late-1970s computer systems and logic controllers. One of the most iconic uses of the 6100 was as the CPU in Digital Equipment Corporation's line of DECmate personal computers. These machines took advantage of the 6100s instruction set to run reduced versions of the operating system used on some PDP-8 machines, although later DECmate computers included a Zilog Z80 for CP/M compatibility.


Intersil 6100 Microprocessor
Crossfiber Optical Switching IC

Here is a device that, while not particularly vintage, is rather unusual; a Crossfiber optical switching chip. A crossfiber chip is a relatively new invention that is used for optical computing and routing. The IC has an array of pinhead mirrors mounted on 2 axis pivots, which can be moved electrically to bounce optical beams in different directions. In normal use, the IC would be mounted in a frame facing a fiber optic array; the mirrors could then be used to direct signals between adjacent fibers. This example contains a 16x16 array composed of 256 mirrors each about a millimeter in diameter; in effect forming a flip dot display intended to be gazed upon by a fiber optic bundle instead of human eyes. The unit shown here is a used laboratory sample and has no manufacturer markings, but we believe it was produced sometime around 2009.

Unfortunately, crossfiber IC's have yet to see widespread availability in the homebrew electronics community. Datasheets and example circuits are not readily available, and the home electronics experimenter is likely to find building a project around one of the these chips a challenging experience.


Crossfiber Optical Switching IC
Atmel AT27C256R

Devices included in this entry:

Atmel AT27C256R (256K leadless carrier; pictured in thumbnail)
Microchip 27C512 (512K leadless carrier)

Atmel's AT27C256R is a 256K EPROM in a tiny surface mount leadless package. Though the majority of modern 27C256 devices are one time programmable IC's in anonymous plastic enclosures, this earlier gold and ceramic example includes a glass window for UV erasure. Later UV erasure versions of this part use an all-ceramic package, but retain the circular UV window.


Atmel AT27C256R EPROM IC
Raytheon HE0909

The HE0909-0-F-002 is a completely undocumented part in an uncommon package. Even the manufacturer of this device is in question, the ceramic package has markings indicating this chip was produced by Teledyne, but electronics lore suggests this device was manufactured by Raytheon. What can be said is that this chip was likely intended for aerospace applications, based on it's unusual construction style. The HE0909 is encased in a flat ceramic carrier with top-mounted leads and a diamond shaped cavity lid. Typically a chip with this type would be installed in a square cutout in the target PCB, allowing the top-mounted leads to lay flat on the pads of the PCB. The black plastic frame is not part of the device; it is a protective carrier designed to support the fragile pins during transport, and would have been discarded when the chip was installed in its final destination.


Raytheon HE0909 Integrated Circuit (HE0909-0-F-002)
Cypress 22V10

The 22V10B is a tiny programmable logic array (PAL), which contains a number of logic gates whose connections can be selected electronically. This chip was manufactured in a number of different package types, the example shown here contains a prominent glass window, which allows the chip to be erased with UV light and re-used. The window covers nearly the entire top surface of the chip, forcing the part number to be printed directly on the window's surface. ICs deployed into commercially manufactured devices typically omit the window to save costs, since the chip would never need to be reprogrammed outside of the factory. The gate array inside the 22V10 is wired in a cross connected matrix and can be programmed to emulate logic systems in the range of 500 to 800 separate gates. The 22V10 also makes use of "Macro Cells" across each of it's 10 outputs, which can be switched to become additional inputs on the fly. The 22V10B shown in the photo was likely manufactured exclusively by Cypress Semiconductor.

Cypress Semiconductor 22V10B Datasheet (PDF)


Cypress 22V10 PAL Logic Array IC (22V10B)
General Instrument P6828

The General Instrument P6828B is an entirely undocumented integrated circuit. No descriptions or information appear to exist on datasheet or partminer sites, and the examples we found did not include any supporting documentation. The device itself is encased in a rectangular gold bathtub package with a white glass base and gold leads. The underside gold leads are arranged in a pin grid pattern and have a square cross-section, most likely to facilitate wire wrap installation. Unfortunately, not much else can be determined from an external examination, and this device is uncommon enough that cutting the lid off of one for a look at the internals seems like borderline heresy.

If you can identify this device, please contact us.


General Instrument P6828 Integrated Circuit (P6828B)
Fairchild FCCD 143D

the FCCD 143D is a linear CCD, which is a light sensor that contains an array of photosensitive elements fixed end to end in a single line. Images are drawn by scanning a beam of light across the length of the CCD, capturing one line at a time. In this device, the light sensitive die has been packaged in a large 28 pin ceramic DIP with a glass cavity lid. The die for this device is much larger than what would be used in a conventional integrated circuit, and spans nearly the entire length of the device.

Fairchild FCCD 143D Linear CCD
Lucent T 7102A

Little is known about the Lucent 7102A, other than that it is an X.25/X.75 protocol controller that was in use in telephone switching equipment in the early 1990s. The most distinctive feature of this IC is it's unusual pin configuration; the underside of the chip contains four rows of pins arranged into four 18 pin DIP arrays, eliminating the need for a custom socket.


Lucent T 7102A Protocol Controller
Westren Electric Integrated Circuits

Devices included in this entry:

Westren Electric 1C parallel to serial interface (16-pin ceramic flat pack; pictured in thumbnail)
Westren Electric 618 APB (16-pin ceramic DIP)

Western Electric manufactured a wide range of obscure and undocumented integrated circuits, many of which featured nondescript packages and a total lack of package-marked part numbers. Like HP, Western Electric IC packages give you nothing, except the vague statement that the device was made by Western Electric. The packages of many Western Electric integrated circuits are so anonymous in appearance that they are frequently misidentified as resistor networks by electronics resellers.


Westren Electric Integrated Circuits
Westren Electric Trimline Controller IC

This bizarre looking hybrid integrated circuit is the controller used in many Western Electric Trimline phone handsets. The device makes use of a rather unusual construction technique in which multiple layers of glass with attached semiconductors and passives are bonded together and coated in resin. Numerous ball bond wires connect the different layers of the integrated circuit electrically. The passive resistors can be clearly seen through the top of the device as tracks of resistive material painted or etched onto the surface of the glass substrate.

Westren Electric Trimline Controller IC

©2000-2024 Industrial Alchemy. All rights reserved. | Switch to mobile version | Contact |