DIFFERENTIAL OPERATIONAL AMPLIFIER WITH LOW VOLTAGE OF ZERO SHIFT Russian patent published in 2011 - IPC H03F3/45 

FIELD: radio engineering.

SUBSTANCE: differential operational amplifier with low voltage of zero shift comprises the first (1) and second (2) input transistors, emitters of which are combined and connected to header of the first (3) auxiliary transistor, the second (4) auxiliary transistor, emitter of which is connected to the first (5) source of supply, base is connected to emitter of the first (3) auxiliary transistor, and collector is connected to the first (6) source of reference current, auxiliary p-n transition (7) connected in parallel to emitter-base transition of the second (4) auxiliary transistor, the first current mirror (8), input of which is connected to collector of the first (1) input transistor, common emitter output is connected to the second (9) source of supply, and collector output is connected to input of the second (10) current mirror, common emitter output of which is connected to the first (5) source of supply, the third current mirror (11), input of which is connected to collector of the second (2) input transistor, common emitter output is connected to the second (9) source of supply, and collector output is connected to collector output of the second (10) current mirror and base of output transistor (12), emitter of output transistor (12) is connected to output of device (13) and via the second (14) current-stabilising dipole is connected to the first (5) source of supply. Circuit additionally includes additional transistor (15), emitter of which is connected to base of the first (3) auxiliary transistor, base is connected to collector of the second (4) auxiliary transistor, and collector is joined to collector of the second (2) input transistor.

EFFECT: reduced absolute value of UCM and its temperature drift.

2 cl, 6 dwg