Ad603 requires a bandwidth gain of 0db to 50db. How to design?

The single chip power consumption of 125mW of the AD603 is about 30mA (both positive and negative power supplies are available), and the input impedance of the AD603 is only100Ω, so it is best to make 50Ω matching when cascading. OPA842 should be very hot because the input impedance of AD603 is too small. In many signal acquisition systems, the amplitude of signal change is relatively large, so the amplified signal amplitude may exceed the range of A/D conversion, so the gain of amplifier must be adjusted accordingly according to the signal change. In a highly automated system, it is hoped that the gain of the amplifier can be controlled by software in the program, or the amplifier itself can automatically adjust the gain to a suitable range. AD603 is such a chip with programmable gain adjustment function. It is a patented product of American ADI, and it is an integrated operational amplifier with low noise and adjustable bandwidth gain of 90MHz. If the gain is expressed in decibels, the gain is linear with the control voltage, the slew rate is 275 V/μ s, and the connection mode between pins determines the programmable gain range. The bandwidth is 90Mhz when the gain is-1~+30 db, and 9MHz when the gain is +9 ~+4 1 dB. Changing the connection resistance between pins can make the gain within the above range. The integrated circuit can be used in RF automatic gain amplifier, video gain control, A/D conversion range expansion and signal measurement system.