DIFFERENTIAL OPERATIONAL AMPLIFIER WITH LOW SUPPLY VOLTAGE Russian patent published in 2011 - IPC H03F3/34 H03F3/45 

FIELD: radio engineering.

SUBSTANCE: differential amplifier (DA) comprises the input differential cascade (DC) (1) with the first (2) and the second (3) current outputs, a buffer emitter follower (EF) (4), the input of which is connected to the second (3) current output of the input DC (1) and via the first (5) collector load dipole (CLD) is connected to the bus of the first (6) supply source (SS), the second (7) CLD connected between the first (2) current output of the input DC (1) and the bus of the first (6) SS, the second (8) bus of SS connected with emitter chains of the input DC (1) and EF (4). The circuit additionally includes an additional matching transistor (9), the emitter of which is connected to the first (2) current output of the input DC (1), the base is connected to the output of EF (4), and the collector is connected to the input of the additional current mirror (CM) (10), besides, the output of CM (10) is connected with the EF input (4), and the common emitter output (11) of CM (10) is connected to the source of potential offset voltage (11).

EFFECT: increased limit values of amplification ratio by differential amplifier voltage at low-voltage supply.

2 cl, 9 dwg