Where to get a logic level diagram for a processor , preferably intel 4004.

i have block diagrams but want it to know more at logic level then transistor level.


The schematics of Intel 4004 may be available here:


Individual components schematics here:

The 4001 ROM
The 4002 RAM
The 4003 Shift-Register
The 4004 CPU


The chip layout was drawn by hand at a magnification of around 500 times the original size. It was drawn over sheet made of Mylar Quadrille material for its dimensional stability.

Ref.: IEEE Solid-State Circuits Magazine ( Volume: 1, Issue: 1, Winter 2009 )

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    \$\begingroup\$ Cool. Let's buy some discrete MOSFETs and a huge PCB. :) \$\endgroup\$ – Oskar Skog Mar 7 '17 at 10:22
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    \$\begingroup\$ @OskarSkog: There have been a few such projects already. E.g. elektormagazine.com/news/…. "Huge PCB" would be an understatement ;) \$\endgroup\$ – MSalters Mar 7 '17 at 11:45
  • \$\begingroup\$ @MSalters 16-bit is quite a different beast than a smaller CPU. 4004 is still entirely reasonable for hand-crafting - I even made a simple 8-bittish CPU myself (though using simple TTLs rather than just transistors - discrete transistors are a bit too slow and unwieldy), and it "only" took about the space of a big tower. Needless to say, pushing it above ~2 MHz is rather impractical, but it was still powerful enough to host a web server (as long as it didn't get more than about five concurrent requests :D). \$\endgroup\$ – Luaan Mar 7 '17 at 14:35
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    \$\begingroup\$ Thanks, for transistor level drawing. If we can get Logic level diagram, then it will be more helpful. \$\endgroup\$ – funlearning Mar 9 '17 at 16:22
  • \$\begingroup\$ There's no logic level diagram of the 4004. It's a bit tedious but not difficult to figure out the gates from the transistor schematic, though. @OskarSkog: See the 6502 from discrete transistors: monster6502.com \$\endgroup\$ – Ken Shirriff Mar 29 '17 at 23:24

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