An input receiver circuit including a single-to-differential amplifier and a semiconductor device including the input receiver circuit are disclosed. The input receiver circuit includes a first stage amplifier unit and a second stage amplifier unit. The first stage amplifier unit amplifies a single input signal in a single-to-differential mode to generate a differential output signal, without using a reference voltage. The second stage amplifier unit amplifies the differential output signal in a differential-to-single mode to generate a single output signal.

Differential power amplifier circuitry includes a differential transistor pair, an input transformer, and biasing circuitry. The base contact of each transistor in the differential transistor pair may be coupled to the input transformer through a coupling capacitor. The coupling capacitors may be designed to resonate with the input transformer about a desired frequency range, thereby passing desirable signals to the differential transistor pair while blocking undesirable signals. The biasing circuitry may include a pair of emitter follower transistors, each coupled at the emitter to the base contact of each one of the transistors in the differential transistor pair and adapted to bias the differential transistor pair to maximize efficiency and stability.