GALLIUM ARSENIDE INPUT DIFFERENTIAL CASCADE OF CLASS AB OF A FAST OPERATIONAL AMPLIFIER Russian patent published in 2022 - IPC H03F3/45 

FIELD: radio electronics.

SUBSTANCE: invention relates to the field of radio electronics and can be used as an input stage of high-speed gallium arsenide operational amplifiers. The gallium arsenide class AB differential input stage of a high-speed operational amplifier contains an input differential stage (1) with the first (2) and second (3) inputs, as well as with the first (4) and second (5) current outputs, the first (6) bus power supply, the first (7) and second (8) output bipolar p-n-p-transistors, the collectors of which are connected to the corresponding first (9) and second (10) current outputs of the device, matched with the first (6) power supply bus, the first (11) and the second (12) current-stabilizing bipolar p-n-p-transistors with combined bases, the emitters of which are connected to the second (13) power supply bus, the collector of the first (11) current-stabilizing bipolar p-n-p-transistor is connected to the first (4) current output of the input differential stage (1) , the collector of the second (12) current-stabilizing bipolar p-n-p-transistor is connected to the second (5) current output of the input differential stage (1). The first (14) and second (15) additional field-effect transistors with a control p-n junction and an n-channel are introduced into the circuit, the drains of which are matched with the second (13) power supply bus, two series-connected additional resistors (16) are connected between their sources and (17), the common node of which is connected to the combined bases of the first (11) and second (12) current-stabilizing bipolar p-n-p transistors, the gate of the first (14) additional field-effect transistor with a control p-n junction and an n-channel is connected to the collector of the first (11) current-stabilizing bipolar p-n-p-transistor and the base of the second (8) output bipolar p-n-p-transistor, the gate of the second (15) additional field-effect transistor with a control p-n-junction and n-channel is connected to the collector of the second (12) current-stabilizing bipolar p-n-p-transistor and the base of the first ( 7) output bipolar p-n-p-transistor, the emitter of the first (7) output bipolar p-n-p-transistor is connected to the source of the first (14) additional a solid field-effect transistor with a control p-n-junction and an n-channel, and the emitter of the second (8) output bipolar p-n-p-transistor is connected to the source of the second (15) additional field-effect transistor with a control p-n-junction and an n-channel.

EFFECT: creation of an input differential op-amp stage implemented on JFET gallium arsenide field-effect transistors with a control p-n junction and bipolar GaAs p-n-p transistors, which provides class AB mode for current outputs, when the maximum DC output currents I_out.max significantly exceed their static values I_out.0, this speeds up the process of recharging the capacitance of the correction capacitor of the op amp and increases the speed of the op amp in the large signal mode.

3 cl, 7 dwg