DIFFERENTIAL AMPLIFIER Russian patent published in 2009 - IPC H03F3/45 

FIELD: physics; radio.

SUBSTANCE: invention relates to radio engineering and communication and can be used as an analog signal amplifier for high internal resistance sensors, in analog microcircuit structures of various purpose (e.g. in operational amplifiers (OA), broad-band and selective amplifiers, filters, etc.). Differential amplifier comprises input bipolar transistor parallel-balance cascade (1), which incorporates the first input (2) and the second input (3), first output (4) and second output (5), reference current source transistor (6), collector of which is connected to common emitter circuit (7) of input parallel-balance cascade (1), and emitter is connected to power source bus (8) via current-stabilising impedor (9), the first secondary transistor (10) and the second secondary transistor (11), bases of which are connected to the first input (2) and the second input (3) of parallel-balance cascade (1), and emitters are interconnected and connected to supplementary current mirror output (12). Conductivity of secondary transistors 10 and 11 is opposite to conductivity of bipolar transistors of input parallel-balance cascade (1). Transistor base of reference current source (6) is connected to input of supplementary current mirror (12), collector of the first secondary transistor (10) is connected to the second input 3 of input parallel-balance cascade (1), and collector of the second secondary transistor (11) is connected to the first input of (2) input parallel-balance cascade (1).

EFFECT: increased input resistance.

2 cl, 5 dwg