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What is an electronic switch called?

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cipherstream

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I want to electronically "switch" a signal line between 2 or more possible paths. I don't need to switch paths very often and when I do it only needs to switch within 100ms or less.

The signal line is 3.3V and the datarate on it can reach 80-100MHz. The direction of the signal can also change due to events/timing that would be very hard to know about in advance.

So basically I need the equivalent of a manual, physical switch, but one that I can switch electronically. I would like to be able to switch using another 3.3V signal line. Once you have thrown a manual switch the signal can pass in either direction, there is no propagation delay and the datarate over it doesn't matter, so this is what I am after.

I have been reading and searching on the internet for a few days, but I am too n00b to know what it is I need. It seems a relay would work, but would be overkill since I would be switching it with the same voltage that I am using it to then pass through. I also read about multiplexers/demultiplexers, but it seemed they only sent a signal one way. I also read about IDT bus switches but I wasn't sure if they sent signals both ways, it looked like they didn't either.

So someone please tell me what it is that will do what I want so I can read up some more about it :)
 

So I need to look at using an analog bidirectional multiplex bus switch? :)
 

Bidirectional multiplexing refers to analog resepectively bus switches.

100 MHz datarate also involves possible problems of source and load impedance, termination and trace impedance, depending on the circuit extensions.

- - - Updated - - -

All standard bus switches are birectional analog switches. The specific parameters for bus switches are high speed and low on-state resistance.
 

After some more reading I wanted to ask; Does the "analog" keyword mean that there is no directional controller?
 

Bidirectional analog switch describes the 4066 IC. Data can go in either direction.
However it's an old device. It may not perform as fast as you require, or at the volt levels you require.

Try an internet search on 4066 switch, and it may lead you to a more modern IC.
 

There are millions of different active switches with constraints for DC, BW, current or Rs, single-side hi/lo and bir-directional.

Here are ON-Semi's patented MOS bidirectional switch used in IC's and also for ADSL
image.jpg

Same is done with NPN & PNP with bipolar base/gate drive .

If CM , common mode isolation is required, tiny reed relay and also ultrafast Optical switches might be possible.
 
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