DIFFERENTIAL AMPLIFIER WITH LOW-RESISTANCE INPUTS Russian patent published in 2010 - IPC H03F3/00 

FIELD: physics; radio.

SUBSTANCE: invention relates to radio engineering and communication and can be used as a device for amplifying high-frequency analogue signals in analogue microcircuits for different functional purposes (for example in communication line drivers, operational amplifiers (OP), high-speed comparators of two voltage values etc). The differential amplifier (DA) with current inputs has first (1) n-p-n and second (2) p-n-p input transistors (T) whose emitters are connected to corresponding first (3) and second (4) current inputs of the DA, a first (5) auxiliary p-n-p T whose collector is connected to the base of the first (1) n-p-n input transistor, a second (6) n-p-n auxiliary transistor whose collector is connected to the base of the second (2) n-p-n input transistor. The base of the first (5) p-n-p auxiliary T is connected to the first (7) bias voltage source, and the emitter is connected to the bus of the first (8) power supply (PS) through a first (9) auxiliary two-terminal circuit. The base of the second (6) n-p-n auxiliary T is connected to the second (10) bias voltage source, and the emitter is connected to the bus of the second (11) PS through a second (12) auxiliary two-terminal circuit. Collectors of the second (5) auxiliary p-n-p T and the second (6) auxiliary p-n-p T are connected to each other through alternating current. The collector of the first (1) n-p-n input T is connected to the emitter of the first (5) p-n-p auxiliary T, and the collector of the second (2) p-n-p input T is connected to the emitter of the second (6) auxiliary n-p-n T.

EFFECT: improved input symmetry of the circuit and, consequently, provision for identical values of transfer constants from inputs to outputs, matched with different power supply buses.

12 cl, 20 dwg