Driving data converters are one of the most popular applications for fully-differential amplifiers. Figure 9-2 shows a typical configuration of an FDA attached to a differential analog-to-digital converter (ADC).

Figure 9-2 Fully-Differential Amplifier Attached to a Differential ADC

FDAs can operate with a single supply. V_OCM defaults to the mid-rail voltage, V_CC/2. The differential output can be fed into a data converter. This method eliminates the use of a transformer in the circuit. If the ADC has a reference voltage output (V_ref), then connect V_ref directly to the V_OCM of the amplifier using a bypass capacitor to reduce broadband common-mode noise.

Figure 9-3 Fully-Differential Amplifier Using a Single Supply