Quad Analog Switch 4066

[Crowbar]

Hi again. I have 3-axis magnetometer. I whant AC coupling to be turned ON or OFF by microcontroller. So for this purpose I decided to use quad analog switch 4066(2 channels for each axis). What can you say about such decision?
Firstly I'm interested in noise characteristics(the switch will be situated between preamplifier and low pass filter).

Best Regards, Konstantin

[Carl-NC]

Depends on how it's used. When closed, the switch is literally a low-value resistor, so it will have some thermal noise. Post a schematic of what you're thinking of doing.

[Crowbar]

PGA202-->RC high pass filter(and here i whant to insert a quad 4066 analog switch to switch DC coupling on or off)-->2 order butterworth filter.

[Crowbar]

Still thinking

[Carl-NC]

So the PGA202 has an output-referred noise of 400nV/rtHz, which is fairly high. A typical 4066 has less than 100-ohms of "on" resistance, which is 1.3nV/rtHz. So you won't even see it.

- Carl

[Crowbar]

It's true, thanks