From WikiChip
MCS-4 - Intel
< intel
Revision as of 00:25, 24 December 2015 by Jon (talk | contribs) (minor additions)

The entire MCS-4 chipset: 4001, 4002, 4003, and 4004.
Developer [[designer::Intel]]
Manufacturer [[manufacturer::Intel]]
Release date November 15, 1971
Architecture 4-bit
Process [[process::10μm]]
Clock 740 kHz

The MCS-4 (Micro-Computer Set-4) or 4000 Series or Busicom Chip Set was a family of 4-bit microprocessor chipsets developed by Intel. The chipset, which was made of four individual chips included the 4004 CPU, the first commercial microprocessor. MCS-4 was completed by March 1971, entered production in June, and introduced into the market on November 15, 1971.


An ad for the 4004 in the Nov. 15, 1971 issue of Electronic News

Before Federico Faggin joined Intel in 1970, the development of the 4004 was stall and dreadful. Federico developed several design innovations at Intel that made it possible to fit the microprocessor in one chip, including new methodology for random logic chip design using silicon gate technology[1]. Faggin developed the 4004 testing tool, chip and logic design concurrently with the layout of all the chips of the entire MCS-4 system.

At the time, Intel was only known for their memory chips. On 15 November 1971, they publicly announced the first commercial microprocessor in the 15th issue of Electronic News. The prophetic ad read: "Announcing a new era in integrated electronics". The chip was designed by Federico Faggin, Ted Hoff and Masatoshi Shima; it received U.S. Patent #3,821,715.

All the MCS-4 components were packaged in 16-pin ceramic DIP. The 16-pin package, which proved to be the most problematic restriction was imposed by management.


The MCS-4 can be minimally functioning with just the 4001 ROM and the 4004 CPU, however its designed to be fully functioning with RAM and shift register.additionally two more chips, the 4008 and 4009 to expand the system to work with any of Intel's existing memory chip selections.

Part Description
4001 ROM
4002 RAM
4003 shift register
4004 CPU
4008 Address latch
4009 I/O Interface


  1. Faggin. Il padre del chip intelligente, Angelo Gallippi, 2002, 88-7118-149-2

Text document with shapes.svg This article is still a stub and needs your attention. You can help improve this article by editing this page and adding the missing information.
Facts about "MCS-4 - Intel"
designer<a href="/wiki/Intel" class="mw-redirect" title="Intel">Intel</a> +
full page nameintel/mcs-4 +
instance ofintegrated circuit family +
main designerIntel +
manufacturer<a href="/wiki/Intel" class="mw-redirect" title="Intel">Intel</a> +
nameMCS-4 +