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Q&A [AD9235]best input method and best driver amp

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[AD9235]best input method and best driver amp

sofy

on Jan 26, 2015

Hello,

According to AD9235 datasheet. There are 2 type of input circuit.

On page 16, Figure 35, AD8138 Positive output go to AD9235 VIN+, negative one go to VIN-.

On the other hand, page 23, Figure 46 shows analog input circuit on AD9235 EVM that AD8138 VO+ go to AD9235 VIN-.

I would like to know, why and which one is the best case for the AD9235 and ADC Driver?

Thank you for your help in advance.

Best regards,

Sofy

0 David.Buchanan

on Jan 27, 2015 7:27 PM over 6 years ago
Hi,

In general the positive output of the amplifier should be routed to the positive input of the ADC to maintain polarity, but the evaluation board design may have decided to cross them for a cleaner layout. This could be compensated in the digital processing by inverting the digital output.

Regards,

David
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0 David.Buchanan

on Jan 27, 2015 9:38 PM over 6 years ago
Hi,

Also, on the driver recommendation, we recommended the AD8138, but a newer amplifier like the ADL5565 would also be a good choice.

Regards,

David
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0 sofy

on Jan 29, 2015 7:04 AM over 6 years ago
Hello, Devid-san,

Thank you very much for your response! It clear for me.

Best regards,

Sofy
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