COMPLEMENTARY CASCODE DIFFERENTIAL AMPLIFIER WITH CONTROLLED GAIN Russian patent published in 2010 - IPC H03F3/45 H03G3/30 

FIELD: physics, radio.

SUBSTANCE: invention relates to radio engineering and communication and can be used in automatic gain control devices, phase detectors and modulators, in phase-locked loop and frequency multiplication systems or as an amplifier whose voltage transfer ratio depends on the control signal level. The controlled amplifier is the basic block of modern systems for receiving and processing high-frequency and microwave signals, and analogue computer and measurement equipment. The complementary cascode differential amplifier with controlled gain has first (1) and second (2) input transistors (T), whose collectors are connected to the input (3) of a current mirror (4), first (5) and second (6) output T, whose bases are combined and connected to the output (7) of the current mirror (4) and a current stabilising two-terminal circuit (8), emitters are connected to corresponding emitters of the first (1) and second (2) input T, and collectors are connected to a load circuit (9). The circuit has a first (10) control T, whose emitter is connected to the first reference current source (11) and through first (12) and second (13) additional resistors to emitters of the first (1) and second (2) input T respectively.

EFFECT: increased suppression of the control signal at the amplifier output.

2 cl, 15 dwg