SBOS710D October 2014 – February 2018 LMH5401
The LMH5401 is designed and optimized for the highest performance to drive differential input ADCs. Figure 68 shows a generic block diagram of the LMH5401 driving an ADC. The primary interface circuit between the amplifier and the ADC is usually a filter of some type for antialias purposes, and provides a means to bias the signal to the input common-mode voltage required by the ADC. Filters range from single-order real RC poles to higher-order LC filters, depending on the requirements of the application. Output resistors (RO) are shown on the amplifier outputs to isolate the amplifier from any capacitive loading presented by the filter.
The key points to consider for implementation are the SNR, SFDR, and ADC input considerations, as shown in this section.