AFE7906: ADC Output attenuation

Koji Kamikariya

Part Number: AFE7906
Other Parts Discussed in Thread: AFE7900EVM

I'm using AFE7906 with a sampling frequency of 2400MHz and a downconverter ratio of 3.

If a single frequency signal around 600MHz is input with this setting, the ADC output may appear to be attenuated in a narrow frequency range of several hundred Hz.

What could be the reason for this?（Fs/4?）
Is there any way to fix this?

over 2 years ago

0 Vijayendra Varma Siddamsetty over 2 years ago

TI__Genius 10875 points

Hi Koji,

Is this on TI EVM or your custom board?

I will check with AFE79xx design team and get back to you.

Regards,

Vijay

0 Koji Kamikariya over 2 years ago in reply to Vijayendra Varma Siddamsetty

Prodigy 10 points

Hi Vijay,

thank you for your reply.

I'm working on my custom board.

However, I have confirmed that the same phenomenon occurs with AFE7900EVM.

This seems to occur when the input signal is Fs/4.

Regards

+1 Vijayendra Varma Siddamsetty over 2 years ago in reply to Vijayendra Varma Siddamsetty

TI__Genius 10875 points

Hi Koji,

In AFE79xx EVM control software, do you see "AFE79xx" in the top left corner? If you see "Latte" instead, you have to uninstall this and install the latest version of the software available secure folder (www.ti.com/mysecuresoftware). I was informed that this issue was fixed in the latest version.

Regards,

Vijay

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AFE7906: ADC Output attenuation