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The Intel 4004 was released by Intel Corporation in 1971 and was the first commercially available microprocessor. The 4004 was a 4-bit CPU, designed for use in the Busicom 141-PF printing calculator[1]. The chip, which is clocked at 740 KHz, employs a 10µm[2] process silicon-gate, capable of executing 92,000 instructions per second. The chip was capable of accessing 4KB of program memory and 640 bytes of RAM. The 4004 was part of the Intel MCS-4 system.
The microprocessor had a limited architecture, such as: only a 3-levels deep stack, a complex memory access scheme, and no interrupt support. In 1974 Intel released an enhanced version of the chip called the 4040.
Contents
History
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[3]. Faggin developed the 4004 testing tool, chip and logic design concurrently with the layout of all the chips of the entire MCS-4 system.
In November of 1971, a memory chip manufacturer by the name of Intel publicly announced the world's first single chip microprocessor, in the Nov. 15 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. The original 4004 chips were shipped in a 16-pin ceramic DIP.
Variations
Three primary source variations were produced by Intel: C4004, D4004 and the P4004. The Intel C4004 was the first chip to be manufactured; it had the gray traces visible on the white ceramic package itself. The C4004 was produced up until mid 1976, when production for the Intel D4004 began. The D4004 had a plastic, black ceramic package. The Intel P4004 is the plastic packaging version.
Only two known secondary sources exists, which has been developed by National Semiconductor and Hitachi since mid-1975. National Semiconductor produced two versions: INS4004J and INS4004D. The INS4004J is a 16-pin black, ceramic DIP, while the INS4004D version is a 16-pin side-brazed, ceramic DIP. The other source was the HD35404 made by Hitachi.
Manufacturer | Model | Package |
---|---|---|
Intel | C4004 | 16-pin Ceramic DIP |
Intel | D4004 | 16-pin Ceramic DIP |
Intel | P4004 | 16-pin Plastic DIP |
National Semiconductor | INS4004D | 16-pin Ceramic DIP |
National Semiconductor | INS4004J | 16-pin side-brazed Ceramic DIP |
Hitachi | HD35404 | 16-pin DIP |
Pinout
The 4004 has 16 pins that are used for i/o, memory controller, clock phases, power and reset.
Pin # | Pin Name | Purpose | Explanation |
---|---|---|---|
1 | D0 | Bidirectional data bus pins | Address and data communication to the ROM and RAM occurs on D0-D3. |
2 | D1 | ||
3 | D2 | ||
4 | D3 | ||
5 | Vss | Main Supply | |
6 | Clock Phase 1 | Clock inputs | |
7 | Clock Phase 2 | ||
8 | Sync | ROM & RAM Sync | Synchronizes the ROM and RAM by signaling the clock is on the raising edge. |
9 | Reset | Reset flag | A logic 1 clears all processor status registers and forces the program counter to jump to address 0x0. The RESET signal must be on for at least 64 clock cycles in order to take effect. |
10 | Test | Test logic state | Signal can be tested via the JCN instruction.
|
11 | CM-ROM | CM-ROM output | ROM selection signal used to retrieve data from memory. |
12 | VDD | VSS -15±5% | |
13 | CM-RAM3 | CM-ROM outputs | Bank selection signal for the 4002 RAM chips in the system. |
14 | CM-RAM2 | ||
15 | CM-RAM1 | ||
16 | CM-RAM0 |
References
- ↑ The Story of the Intel® 4004
- ↑ 4004 Datasheet
- ↑ Faggin. Il padre del chip intelligente, Angelo Gallippi, 2002, 88-7118-149-2