TMUX7234: for Microphone audio signal

Thanks Henry !

It is worth mentioning that Ihe VDD and VSS to TMUX7234  is +5V and -5V.

SG

Hey Henry, SG,

Can you expand on what you mean by deterioted? Relative to what exactly? Adding any passive like an analog mux to the system will have some affect on the THD + N so I would expect the SNR to decrease a bit there but if you mean using the mux with those supplies vs another supply level then that's a different question. Using the TMUX7234, a 44V mux, at +/-5V would actually yield in a little worse performance, relative to say +/-15V, since you're at the very low end of it's operation capabilities. That being said, we do have the +/-5V condition in the datasheet already for THD + N. 

That being said, if the 0.002% THD+N is a little too high for you, you can consider the TMUX2889 which would let you use a single supply but pass +/-5V and is really designed to handle lower frequency audio signals. Do you know what frequency the signals are?

Thanks,
Rami 

Hello Rami,

Thanks for your prompt response. I just want to get an idae, if any negative impact to THD+N and SNR will be if a very low level audio signal (20Hz ~20KHz) passes though the switch. I agree that adding any passive analog mux would yield a bit noise to the performance, I just wonder how much the noise level may have. So I am seeking for suggestions/comments from TI people who has experienced with this device.

TMUX2889 does look a better choice but I do not like its footprint as it may be a problem to me when soldering it. 

Anyway, I think TMUX7234 is acceptable in my current applications now, I will apply it to the circuit design of the amplifier.

Best wishes,

SG

Hi Rami,

Can you advise the THD+N in frequency >7KHz ?

Thanks.

SG

Thanks Rami. Why it improves a bit across high freq. range ? Is it caused by external LPF ?

SG

Thanks for the feedback Rami.