ADA4961 Biasing

On p. 21 of the datasheet, the Coilcraft 0805CS-471 470nH inductor was recommended as the output chokes for the ADA4961. We found that using these chokes caused a 1-dB drop in gain around 1GHz due to their internal parasitics. I suggest either the Coilcraft 0402AF (up to 560nH), the 0402DF (up to 900nH), the 0603AF (up to 1.5uH), or the 0805AF (up to 1.8uH) as the choice for the chokes. When we used the 900nH part, the gain response was much improved.