PRECISION DIFFERENTIAL OPERATIONAL AMPLIFIER Russian patent published in 2011 - IPC H03F3/45 

FIELD: radio engineering.

SUBSTANCE: precision differential operational amplifier comprises the first (1) and the second (2) input transistors, emitters of which are connected to the output of reference current source (3), also joined with the first (4) bus of the supply source, the first (5) auxiliary transistor, emitter of which via the first (6) auxiliary resistor is connected to the second (7) bus of the supply source, the base is connected to the source of shift voltage (8), and the collector is connected to the collector of the second (2) input transistor, the output (9) transistor, the base of which is connected with the collector of the second (2) input transistor, the collector is connected with the second (7) bus of the supply source, and the emitter is connected to the device output and via the current-stabilising dipole (10) is connected with the first (4) bus of the supply source. The source of the reference current (3) comprises the first (11) and the second (12) current mirrors, the outputs of which are combined and are the output of the reference current source (3), the input of the first (11) current mirror is connected with the collector of the first (13) additional transistor, the input of the second (12) current mirror is connected to the collector of the second (14) additional transistor, the bases of the first (13) and the second (14) additional transistors are connected to the base of the first (5) auxiliary transistor, and their emitters via the appropriate first (15) and the second (16) additional resistors are connected to the second (7) bus of the supply source.

EFFECT: reduced Usm and increased Kosp and Kossph.

3 cl, 8 dwg