We would like to design a single multiplication circuit with a multiplier IC, AD835.
The input of the AD835 is a 6M signal from an amplifier, MAX4451, and a 1M signal from an Ardunio broad.
The problem is: when I check the 6M signal from the amplifier without connecting the multiplier, its shape is good.
But, while connecting the 6M and 1M signal as the inputs of the multiplier, both 6M and 1M signals have lots of noise.
I wonder if there's any input warning while connecting to the multiplier, and how to eliminate it?