High-Input-Impedance Single-Ended To Differential Converter

This circuit converts a single-ended analog signal to differential analog signal using two operational amplifiers. In this circuit, the input signal can be considered as being fed to noninverting and inverting amplifiers sharing a resistor that sets the current which will flow through the feedback resistances. The amplifiers produce two output signals which are 180° out of phase. For the inverting amplifier, the input signal appears at the top of the common resistor. Since this signal is not directly coupled but generated only through virtual short circuit, high input impedance is achieved.