A multi-bit flip-flop includes a first flip-flop, a second flip-flop and a first inverter. The first flip-flop has a first driving capability. The second flip-flop has a second driving capability different from the first driving capability. The first inverter is configured to receive a first clock signal on a first clock pin, and is configured to generate a second clock signal inverted from the first clock signal. The first flip-flop and the second flip-flop are configured to share at least the first clock pin.