A receiver circuit receives a signal from a semiconductor device. The receiver circuit includes an input buffer including a first plurality of transistors, the input buffer being configured to detect a fabrication condition of the receiver circuit, generate a control signal according to the detected fabrication condition, and control a gain of an input signal by adjusting a number of operating transistors among the first plurality of transistors in response to the control signal; and a latch circuit configured to latch an output signal of the input buffer, and adjust threshold voltages of a second plurality of transistors in response to a test signal.