The THS4567 device features a unique input common-mode control error amplifier that sets the input common-mode voltage independent of the output common-mode voltage. The VICM error amplifier works by sensing the average voltage at the main amplifiers inputs and then sourcing or sinking an equal amount of current into both the input nodes of the main amplifier to maintain the input common-mode voltage equal to voltage at the VICM pin. If the VICM pin is left floating, its input voltage defaults to 1.5-V above VS–. This voltage is set by the combination of the 8-µA current source and the 181-kΩ resistor shown in Section 7.2. When using the VICM at its default voltage, connect an external capacitor to the VICM pin to bypass the noise from the internal 181-kΩ resistor. The VICM voltage can be set to an arbitrary value by driving the VICM pin externally through a low output impedance source. The input common-mode control loop can be disabled by setting ICM_EN pin low. With the input common-mode loop disabled the THS4567 device behaves like a standard fully-differential amplifier (FDA).