Zilog, Inc. is an American manufacturer of
microprocessor
A microprocessor is a computer processor (computing), processor for which the data processing logic and control is included on a single integrated circuit (IC), or a small number of ICs. The microprocessor contains the arithmetic, logic, a ...
s,
microcontroller
A microcontroller (MC, uC, or μC) or microcontroller unit (MCU) is a small computer on a single integrated circuit. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. Pro ...
s, and application-specific embedded
system-on-chip (SoC) products.
The company was founded in 1974 by
Federico Faggin and
Ralph Ungermann, who were soon joined by
Masatoshi Shima. All three had left Intel after working on the
4004 and
8080 microprocessors. The company's most famous product is the
Z80 microprocessor, which played an important role in the evolution of early computing.
Software-compatible with the Intel 8080, it offered a compelling alternative due to its lower cost and increased performance, propelling it to widespread adoption in
video game
A video game or computer game is an electronic game that involves interaction with a user interface or input device (such as a joystick, game controller, controller, computer keyboard, keyboard, or motion sensing device) to generate visual fe ...
systems and
home computer
Home computers were a class of microcomputers that entered the market in 1977 and became common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a s ...
s during the late 1970s and early 1980s.
The name, pronounced with a long "i" (), is an acronym of ''Z integrated logic'', also thought of as "Z for the last word of Integrated Logic".
History
Zilog was started in
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
in 1974 by
Federico Faggin and
Ralph Ungermann with support and encouragement from
Exxon's computing division.
Both left
Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, and Delaware General Corporation Law, incorporated in Delaware. Intel designs, manufactures, and sells computer compo ...
after working on the
4004 and
8080 microprocessors and custom chips.
Masatoshi Shima, who also worked with Faggin on the 4004 and 8080, joined Zilog in 1975. Ungermann did not want the company to become an Exxon subsidiary and left Zilog in 1978.
On January 1, 1979, Zilog released the first issue of their comic book ''Captain Zilog'', which featured the Z8000 computer. The Z8000, introduced that year, was the company's first 16-bit microprocessor.
The company became a subsidiary of Exxon in 1980. Exxon initially acquired 51 percent of the company before buying it outright; however, the management and employees bought it back in 1989, led by
Edgar Sack.

Zilog went public in 1991, but was acquired in 1998 by
Texas Pacific Group for $527 million. Curtis Crawford replaced Sack and changed the company's direction towards 32-bit data communications processors.
In 1999, Zilog acquired Production Languages Corporation for an unspecified amount less than $10 million.
Bonds were sold against the company to fund the new developments, but after the
Internet bubble burst in 2000 and the resultant reduction in customer demand for such products, Curtis Crawford was replaced by James (Jim) Thorburn, who reorganized the company under
Chapter 11 bankruptcy in late 2001 and refocused it on the 8- and 16-bit microcontroller market.
Jim Thorburn led Zilog back into profitability, and by FY 2007, Zilog had $82 million in sales. During this time, the company developed the Z8 Encore! 8-bit Flash MCU and ZNEO 16-bit Flash MCU product families. In February 2007, Zilog hired Darin Billerbeck to replace Jim Thorburn as president and CEO.
The last year Zilog introduced any new 8-bit microcontroller products was 2007. With no new product road map, FY2008 sales fell 20% to $67.2 million. Sales fell 46% in FY2009 to $36.2 million.
In January 2008, Zilog declined an unsolicited proposal made by Universal Electronics Inc. to acquire the company.
On February 19, 2009, Zilog announced that it had sold off its 8-bit Crimzon Universal Remote Control infrared microcontroller product line, as well as its ARM9 32-bit microcontrollers, including the Zatara security microcontrollers and 15 patents, to Maxim Integrated Products. Remote control manufacturer Universal Electronics Inc. purchased all of Zilog's software and intellectual property assets related to Zilog's universal remote control business, including all ROM code, software, and database of infrared codes. Zilog sold these assets for $31 million cash.
In December 2009,
IXYS Corporation bought the company for $62.4 million in cash, which was significantly below the market valuation of Zilog's stock at the time. Details of the acquisition have been under investigation.

Since early 2010, Zilog has refocused on the industrial and consumer markets for motion detection, motor control, RF wireless and embedded security applications, and is currently producing a number of reference designs that integrate its 8- and 16-bit microcontrollers with IXYS power management products.
In February 2012, Zilog announced the release of its Z8051 family of microcontrollers and tool sets to fill a vacancy in the developer market for
8051 cores that was created when chip-maker
NXP Semiconductors exited the 8051 market. Later that year, Zilog announced its ZGATE Embedded Security solution, which incorporates its eZ80F91 MCU and TCP/IP stack with an embedded firewall to offer protection against cyber threats and attacks at the chip level.
In August 2017, Zilog and its parent IXYS Corporation were acquired by
Littelfuse Inc in exchange for $750 million in cash and stocks.
Microprocessors
Z80
The Z80(i) is an improved implementation of the
Intel 8080 architecture, with substantial extensions to the register model and instruction set and with added hardware interface features.
At introduction, the Z80 was faster, more capable, and much cheaper than the 8080. Alongside the
6502, the Z80 was one of the most popular 8-bit processors for general purpose microcomputers and other applications from the late 1970s well into the 1980s, and while modern CMOS versions of the 6502 are still in production and use today, the Z80 was discontinued in 2024. The Z80 CPU was used in the
Sinclair ZX80,
ZX81,
ZX Spectrum
The ZX Spectrum () is an 8-bit computing, 8-bit home computer developed and marketed by Sinclair Research. One of the most influential computers ever made and one of the all-time bestselling British computers, over five million units were sold. ...
and the
Amstrad CPC
The Amstrad CPC (short for "Colour Personal Computer") is a series of 8-bit home computers produced by Amstrad between 1984 and 1990. It was designed to compete in the mid-1980s home computer market dominated by the Commodore 64 and the ZX Spec ...
home computer
Home computers were a class of microcomputers that entered the market in 1977 and became common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a s ...
s as well as the
MSX
MSX is a standardized home computer architecture, announced by ASCII Corporation on June 16, 1983. It was initially conceived by Microsoft as a product for the Eastern sector, and jointly marketed by Kazuhiko Nishi, the director at ASCII Corpo ...
architecture and the
Microbee and
Tandy TRS-80
The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer developed by American company Tandy Corporation and sold through their Radio Shack stores. Launched in 1977, it is ...
(models I, II, III, 4, and others). The
CP/M-80 operating system
An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs.
Time-sharing operating systems scheduler (computing), schedule tasks for ...
(and its huge software library featuring hits like
WordStar and
dBase
dBase (also stylized dBASE) was one of the first database management systems for microcomputers and the most successful in its day. The dBase system included the core database engine, a query system, a Form (programming), forms engine, and a pr ...
) was known to be ''the'' Z80 disk operating system, and its success is partly due to the popularity of the Z80. The 1985
Commodore 128 added a Z80 to the Commodore 64 hardware allowing it to run CP/M software; the
Digital Equipment Corporation
Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until ...
Rainbow 100 similarly added a Z80 to an Intel 8088-based MS-DOS computer to enable the machine to run both MS-DOS and CP/M software natively.
The Z80 was a common choice for creators of video games during the
Golden age of arcade video games, with a Z80 powering ''
Pac-Man'', dual Z80s in ''
Scramble'', and three in each ''
Galaga'' machine. It was the central processor for the
ColecoVision game console (1982) and
Sega
is a Japanese video game company and subsidiary of Sega Sammy Holdings headquartered in Tokyo. It produces several List of best-selling video game franchises, multi-million-selling game franchises for arcade game, arcades and video game cons ...
's
Master System
The is an 8-bit Third generation of video game consoles, third-generation home video game console manufactured and developed by Sega. It was originally a remodeled export version of the Sega Mark III, the third iteration of the SG-1000 series ...
(1986) and
Game Gear
The is an 8-bit Fourth generation of video game consoles, fourth-generation handheld game console released by Sega on October 6, 1990 in Japan, in April 1991 throughout North America and Europe, and in 1992 in Australia. The Game Gear primarily ...
(1990).
In the 1990s, the Z80 was the CPU of the
Texas Instruments
Texas Instruments Incorporated (TI) is an American multinational semiconductor company headquartered in Dallas, Texas. It is one of the top 10 semiconductor companies worldwide based on sales volume. The company's focus is on developing analog ...
graphing calculator Graphing Calculator may refer to:
* Graphing calculators, calculators that are able to display and/or analyze mathematical function graphs
* NuCalc, a computer software program able to perform many graphing calculator functions
* Grapher, th ...
series, as well as being used as the secondary/support CPU in the
Sega Genesis
The Sega Genesis, known as the outside North America, is a 16-bit Fourth generation of video game consoles, fourth generation home video game console developed and sold by Sega. It was Sega's third console and the successor to the Master Sys ...
(most typically used for sound).
Other chips
After the Z80 Zilog introduced the
16-bit
16-bit microcomputers are microcomputers that use 16-bit microprocessors.
A 16-bit register can store 216 different values. The range of integer values that can be stored in 16 bits depends on the integer representation used. With the two ...
Z8000 and
32-bit
In computer architecture, 32-bit computing refers to computer systems with a processor, memory, and other major system components that operate on data in a maximum of 32- bit units. Compared to smaller bit widths, 32-bit computers can perform la ...
Z80000 processors, but these were not particularly successful, and the company refocused on the
microcontroller
A microcontroller (MC, uC, or μC) or microcontroller unit (MCU) is a small computer on a single integrated circuit. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. Pro ...
market, producing both basic CPUs and
application-specific integrated circuits/standard products (ASICs/ASSPs) built around a CPU core. As well as producing processors, Zilog has produced several other components. One of the most famous was the
Zilog SCC serial communications controller as found on early Apple
Macintosh
Mac is a brand of personal computers designed and marketed by Apple Inc., Apple since 1984. The name is short for Macintosh (its official name until 1999), a reference to the McIntosh (apple), McIntosh apple. The current product lineup inclu ...
,
Sun SPARCstations and SPARCservers up to the
SPARCstation 20.
Zilog also formed a Systems Division, which designed the Zilog System 8000, a Z8000- or Z80000-based
multiuser computer system running a Unix derivative called ZEUS (Zilog Enhanced UNIX System).
Zilog attempted to enter the 32-bit microcontroller market in February 2006 with the demonstration of
ARM9-based Point-Of-Sale (
POS) microcontroller product line. The final product was released in 2007 called Zatara. Sales were disappointing and the entire ARM9 series was sold to Maxim Integrated Products in 2009.
Zilog also produced Zdots single board computers. It includes Zilog eZ80AcclaimPlus controller, 1MB flash memory, 512KB SRAM, 10BaseT Ethernet Controller, IrDA transceiver, 2 x 60-pin system expansion interface with full MPU bus/control signals, RJ-45 Ethernet connector. Motion detection version includes Z8 Encore! XP MCU.
Product list
Microprocessor families
*
Zilog Z80
The Zilog Z80 is an 8-bit computing, 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be Backward compatibility, software-compatible with the ...
(1976)
*
Zilog Z8000 (1979)
*
Zilog Z800 (1985)
*
Zilog Z80000 (late 1985)
*
Zilog Z280 (early 1986)
*
Zilog Z180 (late 1986)
*
Zilog eZ80 (2001)
Microcontroller families
*
Zilog Z380 (1994)
*
Zilog Z8 (1979)
** Zilog
Z8 Encore!
** Zilog
Z8 Encore! XP
*
Zilog eZ8 (2005)
*
Zilog Z16F, ZNEO, 16-bit microcontroller (2006)
*
Zilog Z8051
Zilog, Inc. is an American manufacturer of microprocessors, microcontrollers, and application-specific embedded system-on-chip (SoC) products.
The company was founded in 1974 by Federico Faggin and Ralph Ungermann, who were soon joined by M ...
(2011)
Communication controllers
*Z8030/Z8530 SCC and Z80230/Z85230 ESCC USART chips
*Z16017/Z16M17/Z86017 PCMCIA adapter
*Z80382/Z8L382 microprocessor
*Z5380 SCSI protocol controller (based on
NCR 5380)
*Z022 series single-chip modem
Motion detection
*ZEPIR0AAS02MODG - ZMOTION™ Motion Detection Module
*Z8FS040 ZMOTION™ MCU - Microcontroller with built-in motion detection algorithms
*Z8FS021A - ZMOTION™ Intrusion MCU - Microcontroller with built-in intrusion motion detection algorithms
Digital signal processor
*Z86295
*Z89 series
TV controllers
*Z90231
*Z90233
*Z90251
*Z90255
Line 21 decoders
*Z86129/Z86130/Z86131
*Z86228/Z86229/Z86230
Single board computers
*Zdots eZ80F91
Microcomputers
* MCZ 1 series
* MCZ 2 series
* ZDS series
Local area networking
*Z-Net - local networking architecture
See also
*
Z80-RIO
*
Applied Digital Data Systems
*
LaFarr Stuart, Zilog's 4th employee
References
External links
*
{{Authority control
Electronics companies established in 1974
Companies that filed for Chapter 11 bankruptcy in 2001
TPG Capital companies
Semiconductor companies of the United States
1974 establishments in California
2009 mergers and acquisitions
Companies based in Milpitas, California
Computer companies of the United States