Is it neccessary to create an antialiasing filter for the AD7606?

Hi,

In my recent project, I used the combination of AD8253 and AD7606 to collect analog signals. It is pointed out in the datasheet of the device AD8253 that an anti-aliasing filter (RC filter) should be placed between AD8253 and AD7612. The specific description is shown in the figure below. Now, since AD7606 has built-in input buffer and anti-aliasing filter, is this external RC filter still necessary?

What I want to say is, if it is not necessary then I don’t need to add this part. :)

Thanks.

  • +1
    •  Analog Employees 
    on Feb 27, 2021 11:21 AM

    Hi JJBox,

    You are right, the AD7606 has internally a PGA and low pass filter, allowing for direct sensor interface. Strictly speaking, you will or will not need an external filter depending on your sampling frequency and the frequency corner needed.

    Please see Figure 37 for further info on the internal antialiasing filter.

    Regards,

    Lluis.