Amplifier arrangement

Claim 2

An amplifier comprising, first and second input terminals, first and second output terminals, a common terminal, a first transistor, means connecting the collector-emitter path of the first transistor in series with a first semiconductor junction between the first output terminal and the common terminal so as to form a common junction point between the first transistor and the first semiconductor junction, a second transistor, means connecting a second semiconductor junction in series with the collector-emitter path of the second transistor between the first input terminal and the common terminal, means connecting the first semiconductor junction in shunt with the base-emitter junction of the second transistor, means connecting the base of the first transistor to the first input terminal, a third transistor with its collector-emitter path connected between the second output terminal and the common terminal, means connecting the base of the third transistor to the collector of the second transistor, and means connecting said second input terminal to said common junction point between the first transistor and the first semiconductor junction.

Claim 3

An amplifier as claimed in claim 1 wherein said first and second input terminals, said first and second output terminals, and said common terminal are electrically separate from one another.

Claim 4

An amplifier as claimed in claim 1 wherein said first, second and third transistors are of the same conductivity type.

Claim 5

An amplifier as claimed in claim 3 wherein said first and second semiconductor junctions comprise fourth and fifth transistors of the same conductivity type as the first, second and third transistors, said fourth and fifth transistors being connected as diodes.

Claim 6

An amplifier as claimed in claim 1 wherein said first, second and third transistors are NPN transistors with the collector of the first transistor directly connected to the first output terminal, the collector of the third transistor directly connected to the second output terminal, and the emitters of the second and third transistors directly connected to the common terminal.

Claim 7

An amplifier as claimed in claim 5 wherein said first transistor and said first semiconductor junction are serially connected in the order named between the first output terminal and the common terminal and the second semiconductor junction and the second transistor are serially connected in the order named between the first input terminal and the common terminal.

Claim 8

An amplifier as claimed in claim 1 wherein said first transistor and said first semiconductor junction are connected with the same polarity between the first output terminal and the common terminal and said second semiconductor junction and said second transistor are connected with the same polarity between the first input terminal and the common terminal.

Claim 9

An amplifier as claimed in claim 1 wherein the second semiconductor junction and the second transistor are serially connected in the order named between the first input terminal and the common terminal so that the collector of the second transistor is coupled to the base of the first transistor via the second semiconductor junction.

Claim 10

An operational amplifier comprising an op-amp input terminal and output terminal, a drive amplifier, a current source circuit, and a push-pull output amplifier, said drive amplifier comprising, first and second input terminals, first and second output terminals, a common terminal, first, second and third transistors, first and second semiconductor junction devices, means serially connecting the first transistor and the first junction device between the first output terminal and the common terminal and with the same polarity, means serially connecting the second junction device and the second transistor between the first input terminal and the common terminal, means connecting the base of the second transistor to the anode of the first junction device, means connecting the collector of the second transistor to the base of the third transistor and via said second junction device to the base of the first transistor, a common junction being formed between the first transistor and the first junction device to which the second input terminal is connected, said push-pull output amplifier comprising fourth and fifth transistors of opposite conductivity types connected in series to form a common junction point connected to the op-amp output terminal, third and fourth semiconductor junction devices, means interconnecting the base electrodes of said fourth and fifth transistors via said third and fourth junction devices, means connecting the op-amp input terminal to the base of the fourth transistor via a preamplifier means, means connecting the first input terminal to an output of the current source circuit and the second input terminal to the op-amp input terminal via a high-pass network, and means connecting the first output terminal to the base of the fourth transistor and the second output terminal to the base of the fifth transistor.

Claim 11

An operational amplifier comprising an op-amp input terminal and output terminal, a drive amplifier, a current source circuit, and a push-pull output amplifier, said drive amplifier comprising, first and second input terminals, first and second output terminals, a common terminal, first, second and third transistors, first and second semiconductor junction devices, means serially connecting the first transistor and the first junction device between the first output terminal and the common terminal and with the same polarity, means serially connecting the second junction device and the second transistor between the first input terminal and the common terminal, means connecting the base of the second transistor to the anode of the first junction device, means connecting the collector of the second transistor to the base of the third transistor and via said second junction device to the base of the first transistor, a common junction being formed between the first transistor and the first junction device to which the second input terminal is connected, said push-pull output amplifier comprising fourth and fifth transistors of opposite conductivity types connected in series to form a common junction point connected to the op-amp output terminal, third and fourth semiconductor junction devices, means interconnecting the base electrodes of said fourth and fifth transistors via said third and fourth junction devices, means connecting the op-amp input terminal to the base of the fourth transistor via a preamplifier means, means connecting the first input terminal to an output of the current source circuit and the second input terminal to the op-amp input terminal via a high-pass network, and means connecting the first output terminal to the base of the fourth transistor and the second output terminal to the base of the fifth transistor.

Claim 12

An operational amplifier as claimed in claim 9 further comprising first and second voltage supply terminals, means connecting the push-pull output amplifier across said supply terminals, means coupling the input of the current source circuit to the first supply terminal, and means connecting the common terminal of the drive amplifier to the second supply terminal.

Claim 13

An operational amplifier as claimed in claim 10 further comprising a current mirror circuit having an input, an output and a common terminal, means connecting the current mirror common terminal to the first supply terminal, means connecting the input of the current source circuit to the input of the current mirror and the output of the current mirror to the first output of the drive amplifier.

Claim 14

An operational amplifier as claimed in claim 9 wherein said third and fourth junction devices comprise a sixth transistor and a seventh transistor connected as a diode, said sixth and seventh transistors being serially connected to the drive amplifier second output terminal, the base electrodes of the fourth and fifth transistors being interconnected by the series connection of the base-emitter junction of the sixth transistor and the rectifying junction of the seventh transistor, both connected with the same polarity.