I want to use AD815 in inverting configuration with gain of -2. Is 2k and 1k ohm a good choice?
AD815 is a current feedback amplifier and usually, resistors for gain settings are recommended in the datasheet for optimum performance of the device. "For every CFB op amp there is a recommended value of feedback resistor for maximum bandwidth. If you increase the value of the resistor beyond this value, you reduce the bandwidth. If you use a lower value of resistor below this value, the phase margin is reduced, and the amplifier may become unstable." - excerpt from MT-034:Current Feedback (CFB) Op Amps
I would suggest start to choose the recommended RF in the datasheet first and then select another resistor to yield the closed-loop gain you desired. For example, for the closed gain of -2, you can start with 499 ohms and pick 249 ohms to get your desired closed loop gain.
Thanks Phil for response.
I am curious to know how sensitive is frequency response to these resistor values.
I am using AD815 in unity feedback with 552ohm ( instead of 562ohm) in non-inverting config same as data sheet. I have few degrees phase delay in 19vpp output swing with and without load of 120ohm or 60 ohm.
My application is transducer excitation for ultrasonic beamforming.
Please reply my previous questions.
Also, I need to know how I can measure my AD815 power consumption when I deliver 60vpp output signal to my 75ohm transducer in differential mode ( max current delivery of .4A to my load from each amp). Schematic is below.).