I have a board with an ADA4960 amplifier that is used to amplify a signal between 1 -2 GHz before going into a high-speed ADC. I am having a problem with the amplifier not providing the correct amount of gain given the value of the gain setting resistor. The part is supposed to provide an 18 dB gain with a 0 ohm resistor, but I’m only seeing about 8 dB. I’ve tried changing the gain setting resistor value to 50 Ohms, but it only makes a slight difference (1-2 dB lower) in the gain. I’ve also tried replacing the chip, but no difference in performance. The input is AC coupled with an amplitude of 150mVp-p and the load is 100 Ohms resistive. Power supply is 5V. Why can;t I get 18dB og gain?
-Tim Starr on behalf of RS@ML