Hi, I am using the AD604 evaluation board. The board comes with a 50 ohms terminating resistor on the input (to ground), to accommodate to a 50 ohms source. However, I would like to use the AD604 to for a ultrasound transducer which has a measured frequency dependent resistance between 600 - 60 ohms. The transducer is connected to the amp via a short 0.25m cable. Should I replace the 50 ohms resistor in the AD604 EVAL board with a 600 ohms resistor for impedance matching? While this may achieve a match at one frequency, won't that mean that there isn't a match at other frequencies? Do I even need a terminating resistor at all, since it is often advised that the input impedance of the amplifier should be > 10x source resistance to avoid loading the source. In addition, the terminating resistor at the input contributes extra noise, which I could do without. Any help to clarify this will be appreciated.
