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I was trying to construct a 10x10 cross bar switch using relays -- something like:

enter image description here

Question: is it possible to construct this by using solid state components (power transistors?) -- and if it is how would one go about doing it?

Would appreciate any pointers.

NOTES:

  1. The target application was to be able to wire together discreet analog components: say OpAms, diodes, transistors
  2. I was trying to build a hybrid analog-digital computer -- just for fun -- where the digital side would wire together the analog components using a crossbar switch. Using relays becomes very expansive very quickly say if I wanted to have a 100x100 crossbar.
  3. An attempt at specs: V=36V, Imax = 10mA R ~= 0 (approaching zero -- a few Ohms should be fine) f ~= 0 Hertz [you switch once every few seconds or minutes] -- Note these are what I think would be ideal, a subset or partially covering set should do for now too
  4. So I the cross-bar or equivalent switching fabric could be an Integrated Circuit
  5. The Analog components (discreete) that the will connected to the switching fabric will include: Resistors, Capacitors, OpAms, Transistors, Diodes, Differential Amps, Voltage Summers (if I remember from my undergrad?)
  6. A typical example of circuit that I want to wire together using such a cross bar is below:

enter image description here

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    \$\begingroup\$ Why would it not be possible? \$\endgroup\$ – PlasmaHH Sep 9 '16 at 11:03
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    \$\begingroup\$ V,I or V,R specs are missing \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Sep 9 '16 at 11:19
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    \$\begingroup\$ Since you do not give much requirements I agree with PlasmaHH, it is possible. Andy shows an IC with such a matrix. A limitation of that IC is that the voltage (differences) on the switching nodes are limited. You do not mention any requirement for that. A relay implementation does not care about the voltages. Instead of electromechanical relays you could use solid state relays. \$\endgroup\$ – Bimpelrekkie Sep 9 '16 at 11:20
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    \$\begingroup\$ @user1172468 you might want to specify how much you want to construct this from (discrete) components. The answer you accepted is about options for monolithic chips that implement the desired function. If this is acceptable, you may want to reword your question. \$\endgroup\$ – user2943160 Sep 9 '16 at 11:35
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    \$\begingroup\$ Still need specs for V,R and f of each switch oor switch times \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Sep 9 '16 at 11:35
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Would appreciate any pointers

The MT8816 is an analogue cross point switch: -

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The ISL59532 is a video cross point switch: -

enter image description here

Ditto the HA456: -

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There is also the ADV3202: -

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Or, you could just roll your own using analogue switches wired into a matrix.

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  • \$\begingroup\$ oh wow -- many thanks -- I was looking at the data sheet of the MT8816 -- does a multiplexed circuit essentially act like a copper wire within its operating region -- forgive the lay speak, it's been a couple of decades since I was in school? \$\endgroup\$ – user1172468 Sep 9 '16 at 11:21
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    \$\begingroup\$ An analogue switch might have an on-resistance of several ohms to several tens of ohms and an off-resistance of several Mohms so it's not as good as a relay contact. OMRON produce some very nice (and small) solid state relays that are effectively isolated and offer sub-ohm on resistance. \$\endgroup\$ – Andy aka Sep 9 '16 at 11:25
  • \$\begingroup\$ Several ohms I think would be fine -- what about the inductance (I take it that would be zero for a solid state component) or capacitance \$\endgroup\$ – user1172468 Sep 9 '16 at 11:27
  • \$\begingroup\$ I also updated the question -- I'm trying to create a system that wires together discrete components for the purposes of a simple analog computer \$\endgroup\$ – user1172468 Sep 9 '16 at 11:28
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    \$\begingroup\$ It will be low and definitely sub micro henries. Open circuit capacitance can be quite high and this could be a limitation but try finding the OMRON devices I mentioned. \$\endgroup\$ – Andy aka Sep 9 '16 at 11:28

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