The Intellivision is a home video game console released by Mattel Electronics in 1979. The name is a portmanteau of "intelligent television". Development began in 1977, the same year as the launch of its main competitor, the Atari 2600. In 1984, Mattel sold its video game assets to a former Mattel Electronics executive and investors, eventually becoming INTV Corporation. Game development ran from 1978 to 1990 when the Intellivision was discontinued. From 1980 to 1983, more than 3 million consoles were sold.

The Intellivision was developed at Mattel in Hawthorne, California along with the Mattel Electronics line of handheld electronic games. Mattel's Design and Development group began investigating a home video game system in 1977.Mattel identified a new but expensive chipset from National Semiconductor and negotiated better pricing for a simpler design. Its consultant, APh Technological Consulting, suggested a General Instrument chipset, listed as the Gimini programmable set in the GI 1977 catalog. The GI chipset lacked reprogrammable graphics and Mattel worked with GI to implement changes. GI published an updated chipset in its 1978 catalog. After having chosen National in August 1977, Mattel waited for two months before ultimately choosing the proposed GI chipset in late 1977. A team at Mattel, headed by David Chandler, began engineering the hardware, including the hand controllers. In 1978, David Rolfe of APh developed the onboard executive control software named Exec, and with a group of Caltech summer student employees programmed the first games. Graphics were designed by a group of artists at Mattel led by Dave James.

The Intellivision was introduced at the 1979 Las Vegas CES in January as a modular home computer with the Master Component priced at US$165 and a soon-to-follow Keyboard Component also at $165 (equivalent to $620 in 2021). At Chicago CES in June, prices were revised to $250 for each component. A shortage of key chips from manufacturer General Instrument resulted in a limited number of Intellivision Master Components produced that year. In Fall 1979, Sylvania marketed its own branded Intellivision at $280 in its GTE stores at Philadelphia, Baltimore, and Washington, D.C. On December 3, Mattel delivered consoles to the Gottschalks department store chain headquartered in Fresno, California with a suggested list price of $275. The Intellivision was also listed in the nationally distributed JCPenney Christmas 1979 catalog along with seven cartridges. It was in stores nationwide by mid-1980 with the pack-in game Las Vegas Poker & Blackjack, and a library of ten cartridges. Mattel Electronics became a subsidiary in 1981.

Though the Intellivision is not the first system to have challenged Warner Communications's Atari, it is the first to have posed a serious threat to the market leader. A series of advertisements starring George Plimpton use side-by-side game comparisons to demonstrate the superior graphics and sound of Intellivision over the Atari 2600. One slogan calls Intellivision "the closest thing to the real thing". One example compares golf games where the other console's games have a blip sound and cruder graphics, while the Intellivision features a realistic swing sound and striking of the ball, and a more 3D look. There is an advertisement comparing to the Atari 2600, with the slogan "I didn't know". In its first year, Mattel sold out its initial 175,000 production run of Intellivision Master Components. In 1981, more than one million Intellivision consoles were sold, five times as many as in 1980.

The AY-3-8910 is a 3-voice Programmable Sound Generator, or PSG. It was designed by General Instrumet in 1978 for use with their own 8-bit PIC1650 and their 16-bit CP1610 computers.

The PSG is widely used in many arcade cabinets, pinball machines, and many micro-computers. Here is a list of some of the major brands of computer that used the AY-3-8910:

• Intellivision
• Vectrex
• Amstrad CPC range
• Oric-1
• Color Genie
• Elektor TV Games Computer
• All MSX-1 and MSX-2 computers
• ZX Spectrum home computers

General Instrument spun of MicroChip Technology in 1987 and the chip was sold under the MicroChip brand, and licensed to Yamaha as the YM2149F which the Atari ST range of computers use. Functionally the PSG is very similar to the Texas Instruments SN76489.

Variants:

• AY-3-8910
  Comes with 2 general purpose 8-bit parallel I/O ports, used for Keyboard and Joystick in for instance MSX.
• AY-3-8912
  Same chip, but in a 28-pin package. Parallel port B is not connected to save cost and space.
• AY-3-8913
  Same chip, but in a 24-pin package. Both parallel ports are not connected.
• AY-3-8914
  The AY-3-8914 has the same pinout and is in the same 40-pin package as the AY-3-8910, except the control registers on the chip are shuffled around, and the 'expected input' on the A9 pin may be different. It was used in Mattel's Intellivision console and Aquarius computer.
• AY-3-8930
  Backwards compatible but BC2 pin is ignored
YM2149F
Yamaha Produced chip, same pin-out as the AY-3-8910, but pin 26 could halve the master clock. Can be used to replace the AY-3-8910 if pin 26 is left disconnected.
• YM3439-D
  CMOS version of the Y2149 in 40-pin DIP
• YM3439-F
  CMOS version of the Y2149 in 44-pin QFP
• YMZ294
  Variant of the YM3249 in an 18-pin package. Parallel ports not connected, and all sound channels mixed on 1 port.
• T7766A
  Toshiba variant of the AY-3-8910, fully compatible. Used in some MSX models.
• Winbond WF19054, JFC95101, and File KC89C72: Fully compatible versions of the AY-3-8910 produced for slot machines.