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I have 4 input signals to route on 4x4 outputs. it's not a 1-to-16 demux what i'm looking for. Outputs must be selected 4 by 4.

is there any demultiplexer that can do that on one IC ?

I didn't find quad demultiplexers, I only find dual ones. like: this

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    \$\begingroup\$ Because CPLDs are a thing. \$\endgroup\$ – Ignacio Vazquez-Abrams Jun 10 '15 at 23:36
  • \$\begingroup\$ Any reason you don't just want to use two of the chip you found? \$\endgroup\$ – The Photon Jun 10 '15 at 23:39
  • \$\begingroup\$ Nop, there is no reason, i'm just wondering why it does not exist! at the begining i thought i can reduce budget if i replace 2 ICs by just one. \$\endgroup\$ – Zskdan Jun 10 '15 at 23:44
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    \$\begingroup\$ No. First of all, the chip would have to be in a much larger package because of the number of pins required, so both the parts cost and the cost in terms of board area would in fact be higher than it would be with the two dual chips. Plus, that particular function is needed so rarely, there was no incentive for chip manufacturers to come up with a single-chip solution. \$\endgroup\$ – Dave Tweed Jun 10 '15 at 23:55
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    \$\begingroup\$ Traditionally the 7400 series have been comprised of 14 or 16 pin DIP packages (then SOIC and other SMDs). To do a Quad 1-to-4 would require at least a 30 pin IC, at which point you might as well and not bother investing in a new IC package and socket and just let people use two 16pin dual muxes. \$\endgroup\$ – Tom Carpenter Jun 11 '15 at 0:34
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In the days when it made sense to put such simple logic on its own chip, the standard package was the 0.1inch pin spacing DIP. Standard packages were 14 and 16 pins, later 20 pin packages were added; anything larger than this was an expensive oddball.

So count up the pins you'd need for this circuit:

  • 16 inputs
  • 4 outputs
  • 2 selects
  • probably an enable or output tristate (G) pin for expansion
  • 2 power supply pins Probably 25 but an absolute minimum of 24 pins.

So you're looking at an expensive 28-pin package and a vanishingly small market compared to the commodity parts, which do the same job in two 16-pin parts.

Simplify your inventory, reduce costs and live with the tiny extra board space.

When PALs and later FPGAs came along, you could roll your own (with no Enable!) and the same 24-pin part (probably a 22V10) could fill several roles on the same PCB, so you could buy in enough quantity to make its high price acceptable.

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