The present disclosure provides a medical stimulation system including a plurality of implantable channels each operable to obtain a voltage signal from a designated area of body tissue. The medical stimulation system includes an impedance measurement device. The impedance measurement device includes a plurality of attenuators each coupled to a respective one of the channels. The attenuators are each operable to attenuate an amplitude of the voltage signal received from its respectively-coupled channel. The impedance measurement device includes a multiplexing component that receives the amplitude-attenuated voltage signals from each of the attenuators. The multiplexing component selectively outputs two of the amplitude-attenuated voltage signals. The impedance measurement device includes a differential amplifier that receives the two amplitude-attenuated voltage signals outputted from the multiplexing component as a differential input signal. The differential amplifier generates an amplifier output signal that includes an at least partially amplified version of the differential input signal.