Just wondering if anyone knew if the ADL5390 could be used any lower than the 20 MHz specified in the datasheet. I saw another product reference that specified 10 MHz as the lowest frequency for the part. I was wondering if the freq range specified was just a function of the external coupling/matching components or if it was inherent to the IC itself. I'd like to use it over a range of about 5-50 MHz if possible.
Unfortunately, the part inherently degrades linearity and gain as you go lower than approximately 70 MHz. Check out Figures 16, 17, and 31 in the datasheet. It will function at frequencies less than 20 MHz, but I don't know how usable it will be for your application.
What is your specific application and your requirements?