SBOS710D October 2014 – February 2018 LMH5401
The CM input controls the output common-mode voltage. CM has no internal biasing network and must be driven by an external source or resistor divider network to the positive power supply. The CM input impedance is very high and bias current is not critical. The CM input has no internal reference and must be driven from an external source. Using a bypass capacitor is required. A capacitor value of 0.01 µF is recommended. For best harmonic distortion, maintain the CM input within ±1 V of the midsupply voltage using a 5-V supply and within ±0.5 V when using a 3.3-V supply. The CM input voltage can operate outside this range if a lower output swing is used or distortion degradation is allowed. For more information, see Figure 21 and Figure 22.