Analytical design of small-signal amplifier with maximum gain in conditionally stable region

The source and load impedances required to realize the maximum small-signal gain are analytically derived to exceed the maximum stable gain (MSG) in the conditionally stable region. The maximum gain is useful for millimeter-wave amplifiers in which the MSG of MOSFETs is less than 10dB. The design procedure of an amplifier is described with reference to the derived source and load impedances. It is demonstrated that a balanced amplifier can achieve high gain while satisfying reflection characteristics.