2

I'm designing a circuit that would switch between stereo-jack inputs. Source audio would be plugged into one end, and on the other two ends, two different audio outputs. I want to be able to switch between one of the two outputs.

Physically, I know how to do this, it is very simple using a double throw switch.

However, if I want to do this digitally, using a micro-controller board to control the switching, what type of component would I use?

I know that the digital equivalent of a SPST is an NPN-transistor. What is the digital equivalent of DT switch? Any support multiple poles?

A poor diagram of what I want to do.

Switcher

cdahmedeh
  • 23
  • 3

1 Answers1

2

What you're looking for is an analog switch. The control lines are selected via digital IO but the signals passing through are analog.

Chris Ryding
  • 556
  • 2
  • 7
  • 1
    While I would also go for an analog switch in the first instance, if for some reason they are unsuitable (e.g. biasing problems, or problems with the series resistance of a few hundred ohms they typically exhibit) then a DP3T relay might be more suitable. – markt Apr 21 '14 at 04:12
  • @markt - There are ~2Ω series resistance analog switches. Or you could always buffer the signal after the analog switch. – Connor Wolf Apr 21 '14 at 14:15
  • @ConnorWolf All true, but a fair bit of extra electronics. A relay & driver is very minimalist. – markt Apr 22 '14 at 09:35
  • Thanks everyone for your insightful answers! I think I will use a double-throw relay. They seem to be pretty easy to find. – cdahmedeh Apr 24 '14 at 06:48