Patent ID: 7265623
Filing Date: 2007-09-04
Classification: H03F

Abstract:
1. A differential amplifier comprising: (a) first and second transistors having respective first and second drain nodes through which sum-constant currents respectively flow; and (b) first and second variable drain impedances respectively coupled to the first and second drain nodes, each of the variable drain impedances having an inductance (L), a capacitance (C) and a resistance (R), wherein at least said resistance (R) of each of the first and second variable drain impedances is adjustable and wherein at least one of said L and C of each of the first and second variable drain impedances is independently adjustable so that an output voltage versus the input voltage transfer function of the differential amplifier can exhibit a peak gain at a corresponding peak boost frequency which is greater than a base gain of the differential amplifier at 0 Hz and so that the peak gain and base gain can be adjusted independently of one another.