An input buffer includes an amplifier circuit, such as a differential amplifier circuit, inverting amplifier circuit or pull-up/pull-down amplifier circuit. A momentary boost circuit is coupled to an input buffer input terminal, an input terminal of the amplifier circuit, and an output terminal of the amplifier circuit, and is operative to generate a boosted input signal at the input terminal of the amplifier circuit from an input signal at an input buffer input terminal for an interval that is terminated responsive to an output signal at the output terminal of the amplifier circuit. The momentary boost circuit may include a detector circuit coupled to the output terminal of the amplifier circuit and operative to generate a control signal responsive to a transition of the output signal, and a boost circuit, coupled between the input buffer input terminal and the input terminal of the amplifier circuit and operatively associated with the detector circuit, that receives the input signal at the input buffer input terminal and generates the boosted input signal at the input terminal of the amplifier circuit from the received input signal responsive to the control signal. For example, the boost circuit may include a capacitor coupled between the input buffer input terminal and the input terminal of the amplifier circuit, and a switch that couples and decouples the input terminal of the amplifier circuit to a reference voltage source responsive to the control signal. The detector circuit may be operative to generate a pulse responsive to a transition of the output signal, and the switch may be operative to couple the input terminal of the amplifier circuit to the reference voltage source responsive to the pulse.