DIFFERENTIAL AMPLIFIER WITH WIDER ACTIVE OPERATION RANGE Russian patent published in 2008 - IPC H03F3/45 

FIELD: radio technology.

SUBSTANCE: invention pertains to radio technology and communications and can be used as a device for amplifying analogue signals, in the structure of analogue microcircuits with various functions (for example, operational amplifiers, comparators) with low current use in the static mode. The differential amplifier has an input differential cascade (1) with first (2) and second (3) current outputs, a static mode stabilisation circuit (4) in the common emitter circuit of the differential cascade (1), with a non-inverting input (5), first (6) and second (7) transistors (T) of a feedback circuit, first (8) and second (9) current stabilising two-terminal circuits. The base of the first T (6) of the feedback circuit is connected to the first (2) current output of the differential cascade (1) and the first current stabilising two-terminal circuit (8). The base of the second T (7) of the feedback circuit is connected to the second (3) current output of the differential cascade (1) and the second current stabilising two-terminal circuit (9). The collector of the first T (6) and the second T (7) of the feedback circuit are connected to the non-inverting input (5) of the static mode stabilisation circuit (4). The circuit has a first (10), second (11) and third (12) current mirrors. The emitter of the first T (6) of the feedback circuit is connected to the input of the first current mirror (10). The emitter of the second T (7) of the feedback circuit is connected to the input of the second current mirror. The output of the first current mirror (10) is connected to the input of the third current mirror (12). The outputs of the second current mirror (11) and the third current mirror (12) are connected together and to the output (13) of the differential amplifier.

EFFECT: increased maximum level of output current of the differential amplifier in a wide range of variation of the output voltage, closer to supply voltage.

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