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I have been looking for 16-bit ICs for a project i`m working on. The project is to build a 16-bit computer from scratch, therefor i decided i nedded cgips that could handle high clock-frequensies. Durring my serch for an optimal IC type i decided that the FAST Advanced Schottky TTL. The problem is that the size of the connectors are to small to fit on a normal breadboard (1 in or 2.54mm).

Are there bigger versions of the same chip sets? If not, are there other IC that fit while still fulfilling the requirements i need for high frequencies?

eks: http://cache.nxp.com/documents/data_sheet/74AVC16374.pdf?pspll=1

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marked as duplicate by The Photon, PeterJ, uint128_t, Daniel Grillo, PlasmaHH Apr 7 '16 at 14:57

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    \$\begingroup\$ You should be able to find lots of Fast TTL parts in DIP packages, but probably not much over 24 pins. That will probably rule out most native 16-bit parts, so you'll have to construct 16-bit functions from 8-bit parts. \$\endgroup\$ – The Photon Apr 6 '16 at 22:03
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    \$\begingroup\$ Incidentally, what did you have in mind as "high frequencies"? Because the breadboard itself (and the long unreferenced wires you'll use to connect breadboard rows), will likely limit you to no more than 1 or 2 MHz. \$\endgroup\$ – The Photon Apr 6 '16 at 22:08
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    \$\begingroup\$ A breadboard for FAST TTL is an oxymoron. Although it conforms to the same specs in terms of logic levels as Schottky, my experience suggests it does so more tightly, and errors due to ground bounce are a big problem. If I had no prorotype with it I'd be using a board with a good solid ground plane, NOT a breadboard. (That could be simple copper-clad, with the chips upside down, "dead bug" style) \$\endgroup\$ – Brian Drummond Apr 6 '16 at 22:52
  • \$\begingroup\$ OP, could you please edit your question to fix the multitude of spelling errors? \$\endgroup\$ – uint128_t Apr 7 '16 at 2:22
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If you're looking to build up a computer out of discrete logic, and you're fixing to use breadboards, don't bother with FAST. Although you can easily get many of the 7400 series parts in FAST (search on 74F374, for instance), breadboards, at least solderless breadboards, will simply not support clock rates which make FAST necessary. The circuits get too spread out and the wires (particularly clocks) get too long to work reliably. Additionally, the TTL/LSTTL/ALSTTL/FAST/etc families are pretty much restricted to 4 bit logic functions (including ALUs) and 8 bit storage/bus functions. 16 bit functions never were much available, in part because the packages get so big. A 16-bit register, for instance, would require at least 36 pins, probably on a 0.6 wide DIP, and two 20-pin packages take up less room. There are some exceptions, such as multipliers, but they are few and far between.

Frankly, I'd recommend the 74HC family. If nothing else, the reduced power requirements will make your project far easier. Any sort of FAST system with any complexity will take amps at 5 volts, and most likely 10s of amps.

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With few exceptions TTL chips never advanced over 8 bits so they are either 4 bit (ALU) either 8 bit (D-latches/buffers/registers).

So my advice is to focus on the design than looking around for any exotics that couldn't fit your breadbord.

Hope this helps.

P.S. What 'High Frequencies' mean in your design?

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