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Okay so I'm looking for an IC or anything that contains a large number of controllable switches.

Say for instance, 100 switches. Each switch must have an independent input and output. I don't want to select from them, so I don't need a mux/demux. I essentially want all 100 of them to be individually controllable, which I suppose would require 100 bits of control, so if an IC did exist it would have to be at least 300+ pins

Is there any way to do this? I'm doubtful that there's an IC that can do this, but maybe there's a solution I haven't heard of.

Any help is appreciated. Thanks.

EDIT with crosspoint

So I realize I could connect different points to every other point with a crosspoint switch that had 2x as many pins as connection points, sort of like this.

enter image description here

But this results in a lot of wasted switches. Out of the 16 switches in this 4x4 crosspoint, only 6 are needed, so 10 are wasted.

Optimally, I should only need 6, like so:

enter image description here

Also, I think it's possible to connect by using a cross point that has the same amount of total IO as connection points I need, like this:

enter image description here

But to connect any point back to the same side, I would have to use up one of the points on the other side. Like {A-C-B}

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    \$\begingroup\$ Can you use an FPGA? \$\endgroup\$ Commented Sep 25, 2013 at 15:47
  • \$\begingroup\$ What are you switching? Logic? Analog? ... specs needed \$\endgroup\$ Commented Sep 25, 2013 at 15:49
  • \$\begingroup\$ Analog, but very low current, so preferably analog switches. Yeah I could use an FPGA, but I don't know how to get around the lack of I/O problem. 100 switches would need 100 inputs, 100 outputs, 100 control bits, and whatever else \$\endgroup\$ Commented Sep 25, 2013 at 15:50
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    \$\begingroup\$ Maybe this could work? analog.com/en/switchesmultiplexers/analog-crosspoint-switches/… \$\endgroup\$ Commented Sep 25, 2013 at 15:53
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    \$\begingroup\$ For a 100 switch part you could significantly reduce the number of required I/O pins if the 100 control sugnals were on-chip and driven from the outputs of a serial register scheme. Such register could be loaded via an I2C or SPI interface. \$\endgroup\$ Commented Sep 25, 2013 at 16:10

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For individual control, twenty-five CD4066 switches would work for you. They are about $0.50/ea from a distributor. Or cheaper from China, Futurelec, etc.

If you are controlling this from a microcontroller, it will be more convenient to set up a daisy-chain of thirteen ADG714s, and control them via SPI bus. These are almost $5 each from distributors, but the switches themselves have better specs.

The cheapskate microcontroller solution is to use the CD4066 switches but control them with digital shift registers like a chain of thirteen 74hc595.

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