Hi
We are building a multiple channel signal conditioning system, with signal frequency of 300kHz. We want to use 8:1 multiplexers to feed 8-channel bandpass filter outputs into a signle VCA, to save power and buget. The sampling frequency we are using is 400kHz for each channel, and in consequence 3.2MHz for the ADC. The VCA is AD605 from ADI, with an input resistor of about 175 ohm.
What we are interested is whether SN74LV4051A is suitable for our design, and the most important index we thought is the "dynamic crosstalk", which measures the coupled signal level of un-feeded channels, when only one channel is feeded with a 300kHz sine wave, and the multiplexer is operating with a clock of 3.2MHz.
We have tested different multiplexers from ADI and LTI, all of these show a dynamic crosstalk above -51dB at such a operating clock, although the static crosstalk (when the multiplexer is not switching) in their datasheet are all below -60dB.
Can someone from TI do a test and tell us the results?
thanks!
Feng Sun
