Low Current Analog Switching

I've got a couple low current low voltage audio signals that I want to switch between before they go into my audio amp and out to a speaker. I've not found a lot of good options for analog switching - anyone have any ideas on this? Thanks!

bacterozoid said:

I've got a couple low current low voltage audio signals that I want to switch between before they go into my audio amp and out to a speaker. I've not found a lot of good options for analog switching - anyone have any ideas on this? Thanks!

Click to expand...

hi,
There is a good range of analog ic's available.
HEF 4016, 4051, 4052, 4053 and 4067 all suitable for low level audio.

Those look pretty useful - I'll look into using one of those. Thanks for the quick response!

The CD405x ICs produce distortion of asbout 0.1% when they have a 10V sipply and feed a 10k load. A MAX405x IC is improved, is almost impossible to find and is expensive but it can feed a 600 ohm load with low distortion.

Use a normal CD4051 instead. It's available anywhere.

Boncuk

If you want to avoid the use of coupling capacitors and such, you can also choose the DG470 which can operate well from +/- power supplies. It has a modest ON resistance too.

There is a point to DC coupling audio circuits at 0 volts, especially switches. Biasing everything at ground and DC coupling means that there are no coupling capacitors charging and discharging when you turn things on and off, so you avoid popping sounds and other transients.

Oh, I've just noticed that the 405x series also manages bipolar supplies with ease. I'd still recommend the DG470 for its lower distortion and R(on).

Another option is to use a virtual earth circuit to bias the usual 0V point at half the supply voltage.

Siliconix also has a variety of analog switches:
Analog switches and multiplexers - Vishay

Edit: Oh, I see RadioRon has already pointed to one of the Siliconix DG series.

Thanks all - these look like some good options