A semiconductor system may include a first semiconductor device and a second semiconductor device. The first semiconductor device compares a received signal with an original signal to generate a driving force control signal. The first semiconductor device also drives the original signal using a driving force in accordance with the driving force control signal to output an external transmission signal. The second semiconductor device receives the external transmission signal to generate a positive signal and a negative signal. The second semiconductor device also generates a restoration signal in response to the positive signal and the negative signal. The second semiconductor device additionally outputs the restoration signal as the external transmission signal to the first semiconductor device.