ADS7049-Q1EVM-PDK: Analog Input Circuit for ADS7049 EVM

joe lindula

Hello, I would like to ask the forum guru's what is the purpose of the 0.015uF Cap in parallel with the 1Mohm resistor in the ADS7049-Q1EVM-PDK?

Also, is R5 49.9 ohms required to match R2 in order to have a Unity Gain? I see that I can add some Gain by adding R1, is that correct?

Thank you,

Joe

over 3 years ago

0 Cynthia over 3 years ago

TI__Mastermind 24940 points

Hello,

The resistor and capacitor are to help some impedance matching to common terminal values, as well as to add some filtering to the input. The 1Mohm resistor is ground the input by simply leaving the input floating (not connecting a input signal to the board)

As for the feedback resistor, it is not necessary to match R2 to R5. R2 and R1 can be changed to put the amplifier in gain.

Regards

Cynthia

0 joe lindula over 3 years ago in reply to Cynthia

Mastermind 6850 points

Thank you very much.

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ADS7049-Q1EVM-PDK: Analog Input Circuit for ADS7049 EVM