Hi all,
I'm trying to drive an ADS5463 ADC with a signal that is amplified by the LMH6881 eval board, schematic: www.ti.com/.../snor004.pdf, providing a single-ended output. However, at the max gain setting on the LMH6881, we still aren't getting as much gain as we'd like. We have tried using a Mini-Circuits RF plug-in amplifier cascaded in series with the output of the LMH, and although amplification is then sufficient, noise is too high (SNR almost 1:1). Our goal is to amplify up to 200MHz. My question: Is there a good way to cascade another high speed amplifier with the output of the LMH without creating too much noise (we need an additional 10-15 dB of gain), or is it best to do all the amplification in one stage?
Thanks for your thoughts!