32 analog inputs multiplexing with ADS805

[djnik1362]

hi
This is timing diagram from ADS805 datasheet :



I have 32 analog inputs that connected to a 32x1 analog multiplexer.

My question is :

With given timing diagram how can i read 32 analog channels ?

I need to sample each channel at about 200KHz frequency.

Thanks for your support.

 

[erikl]

I have 32 analog inputs that connected to a 32x1 analog multiplexer.

With given timing diagram how can i read 32 analog channels ?

I need to sample each channel at about 200KHz frequency.

If 200kHz is your channel switching frequency, you've got 5µs/channel. And your ADS805 needs only 300ns per conversion, if I understand the timing diagram correctly. So there's plenty of time margin, isn't it?

 

[FvM]

Although it's feasible in terms of ADC sampling speed, it's not so easy to achieve 12 bit accuracy with the multiplexer design.