JAJSEA6B December 2017 – February 2019 LMH5401-SP
PRODUCTION DATA.
The LMH5401-SP can also be used to amplify differential input signals to differential output signals. In many ways, this method is a much simpler way to operate the FDA from a design equations perspective. Again, assuming the two sides of the circuit are balanced with equal RF and RG elements, the differential input impedance is now just the sum of the two RG elements to a differential inverting summing junction. In these designs, the input common-mode voltage at the summing junctions does not move with the signal, but must be dc biased in the allowable range for the input pins with consideration given to the voltage headroom required to each supply. Slightly different considerations apply to ac- or dc-coupled, differential-in to differential-out designs, as described in this section.