Rotary switch electronic alternative

Thread Starter

teddyng

Joined Nov 12, 2019
6
Are there any simple alternative to a rotary switch that can be control via software and not a physical turn. The only alternative I can think of is a series of relays, but for a SP8T for example would require a 7 relays.
 

Thread Starter

teddyng

Joined Nov 12, 2019
6
I think I am looking for something like CD4066 which seems to be a bilateral switch so I guess can be used for data. I just need to find a SPDT or DPDT version of it. I've never used IC switch before so not really sure how they work. My plan is to control them with a raspberry pi zero or arduino mini with an ESP chip, so I can switch them remotely.
 
Last edited:

crutschow

Joined Mar 14, 2008
25,114
You could likely use a multiplexer, such as a 74HC4051 (8-channel), or a 74HC4067 (16-channel).
These provide a low impedance path (100 ohms or so with a 5V supply voltage) between the in and out (bilaterial) for the selected channel.
One limitation is that the signal voltage must be between ground and the supply voltage (which should be the case for USB data).
 

Thread Starter

teddyng

Joined Nov 12, 2019
6
You could likely use a multiplexer, such as a 74HC4051 (8-channel), or a 74HC4067 (16-channel).
These provide a low impedance path (100 ohms or so with a 5V supply voltage) between the in and out (bilaterial) for the selected channel.
One limitation is that the signal voltage must be between ground and the supply voltage (which should be the case for USB data).
Cheers, just ordered some on ebay, will give that a try.
 

AnalogKid

Joined Aug 1, 2013
8,487
Older CMOS analog switches (4066, 4051, etc.) probably have too high an ON resistance for USB operation. I think Linear Tech or Maxim make USB-specific switch devices. If not, there are "bus switch" parts that have an on resistance of something like 5 ohms and are built for speed.

ak
 

Thread Starter

teddyng

Joined Nov 12, 2019
6
Older CMOS analog switches (4066, 4051, etc.) probably have too high an ON resistance for USB operation. I think Linear Tech or Maxim make USB-specific switch devices. If not, there are "bus switch" parts that have an on resistance of something like 5 ohms and are built for speed.

ak
That's sound quite good I will have a look. I am just using some relays at the moment with about 1-2 ohms resistance. Problem is just the size of having 14 SPDT is just a bit stupid, or I can source some DPDT ones so is only 7 DPDT for both of the data lines. Of course going to ICs switch would be a lot better and less noise and I only require to put one each for the data line.
 
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