Provided is a semiconductor device to prevent DC current from flowing between differential input signals. The semiconductor device includes a first input unit configured to buffer a first signal of differential input signals, a second input configured to buffer a second signal of the differential input signals, and a latch coupled between a first repeating node of the first input unit and a second repeating node of the second input unit to prevent duty variation of the first and second signals. The semiconductor device further includes a latch controller configured to selectively switch the operation of the latch based on states of the first and second signals appearing at the first and second repeating nodes during a time interval before preambles of the differential input signals are received.