Two-terminal negative resistance device employing bipolar-unipolar transistor combination

Claim 2

An electrical network having two terminals, the Network having a bipolar transistor with its collector and emitter connected in a series path from one to the other of the terminals, and a field effect transistor having its gate electrode connected to one of the terminals and its source-drain path connected from a resistive bias circuit to the base of the bipolar transistor, the resistive bias circuit being connected from one to the other of the terminals, the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable.

Claim 3

An electrical network as claimed in claim 1 also including a negative feedback arrangement to improve the linearity of the network.

Claim 4

A network as claimed in claim 1 wherein first and second bias resistance means are connected in series from one terminal to the other and the source-drain path of the field effect transistor is connected from the junction of the first and second bias resistance means to the base of the bipolar transistor.

Claim 5

A network as claimed in claim 3 wherein the field effect transistor is of the depletion type.

Claim 6

A network as claimed in claim 1 wherein first and second bias resistance means are connected in series from one terminal to the other, the field effect transistor is of the depletion type, the collector of the bipolar transistor and the gate of the field effect transistor are connected to one terminal, the emitter of the bipolar transistor being connected to the other terminal, and the source-drain path of the field effect transistor is connected from the junction of the first and second bias resistance means to the base of the bipolar transistor.

Claim 7

A network as claimed in claim 2 further including an active semiconductor device connected in a series bias resistance circuit from one terminal to the other, the said device being operative to provide negative feedback to improve the linearity of the network.

Claim 8

An electrical network having two terminals, the network having: first resistance means, second resistance means, the source-drain path of a first field effect transistor, third resistance means and fourth resistance means connected in the order stated in series from one terminal to the other, the gate of the first field effect transistor being connected to the said other terminal, a first bipolar transistor of one conductivity type having its collector connected to the said one terminal, its emitter connected through fifth resistance means to the said other terminal, and its base connected to the junction of the first and second resistance means, a second bipolar transistor of the opposite conductivity type having its emitter connected to the base of the first bipolar transistor and its collector connected to the junction of the third and fourth resistance means, a second field effect transistor of the depletion type having its source-drain path connected from the junction of the second resistance means and first field effect transistor to the base of the second bipolar transistor, the gate of the second field effect transistor being connected to the said other terminal, the arrangement being such that, in use, the voltage-current characteristic of the network contains a region in which increase in current through the network results in a decrease in the voltage across the network.

Claim 9

An electrical network having two terminals, the network having: first resistance means, second resistance means, the source-drain path of a first field effect transistor, third resistance means and fourth resistance means connected in the order stated in series from one terminal to the other, the gate of the first field effect transistor being connected to the said other terminal, a first bipolar transistor of one conductivity type having its collector connected to the said one terminal, its emitter connected through fifth resistance means to the said other terminal, and its base connected to the junction of the first and second resistance means, a second bipolar transistor of the opposite conductivity type having its emitter connected to the base of the first bipolar transistor and its collector connected to the junction of the third and fourth resistance means, a second field effect transistor of the depletion type having its source-drain path connected from the junction of the second resistance means and first field effect transistor to the base of the second bipolar transistor, the gate of the second field effect transistor being connected to the said other terminal, the arrangement being such that, in use, the voltage-current characteristic of the network contains a region in which increase in current through the network results in a decrease in the voltage across the network.

Claim 10

An electrical network having two terminals, the network having: a bipolar transistor with its collector and emitter connected in a series path from one terminal to the other, and a bias circuit connected from one to the other of the terminals for supplying base current to the bipolar transistor, the bias circuit comprising resistance means and a field effect transistor having its source-drain path connected from the base to the emitter of the bipolar transistor, the gate of the field effect transistor being connected to onE of the terminals, and the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable.

Claim 11

An electrical network having two terminals, the network having: a bipolar transistor with its collector and emitter connected in a series path from one terminal to the other, and a bias circuit connected from one to the other of the terminals for supplying base current to the bipolar transistor, the bias circuit comprising resistance means and a field effect transistor having its source-drain path connected from the base to the emitter of the bipolar transistor, the gate of the field effect transistor being connected to onE of the terminals, and the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable.

Claim 12

A network as claimed in claim 8 wherein the field effect transistor is of the depletion type.

Claim 13

An electrical network having two terminals, wherein: first resistance means is connected from one terminal to the base of a bipolar transistor, second resistance means is connected from the emitter of the bipolar transistor to the other terminal, the collector of the bipolar transistor is connected to the said one terminal, the source-drain path of a depletion type field effect transistor is connected from the base to the emitter of the bipolar transistor, and the gate of the field effect transistor is connected to the said other terminal, the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which the increase in one of the variables voltage or current causes a decrease in the other variable.

Claim 14

An electrical network having two terminals, wherein: first resistance means is connected from one terminal to the base of a bipolar transistor, second resistance means is connected from the emitter of the bipolar transistor to the other terminal, the collector of the bipolar transistor is connected to the said one terminal, the source-drain path of a depletion type field effect transistor is connected from the base to the emitter of the bipolar transistor, and the gate of the field effect transistor is connected to the said other terminal, the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which the increase in one of the variables voltage or current causes a decrease in the other variable.

Claim 15

An electrical network having two terminals, wherein: first, second and third resistance means are connected in the order states in series from one terminal to the other, the collector of a bipolar transistor is connected to the junction of the first and second resistance means, the emitter of the bipolar transistor is connected to the said other terminal, the gate of a depletion type field effect transistor is connected to the said one terminal, and the source-drain path of the field effect transistor is connected from the junction of the second and third resistance means to the base of the bipolar transistor, the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable, negative feedback being provided to improve the linearity of the network.

Claim 16

An electrical network having two terminals, wherein: first, second and third resistance means are connected in the order states in series from one terminal to the other, the collector of a bipolar transistor is connected to the junction of the first and second resistance means, the emitter of the bipolar transistor is connected to the said other terminal, the gate of a depletion type field effect transistor is connected to the said one terminal, and the source-drain path of the field effect transistor is connected from the junction of the second and third resistance means to the base of the bipolar transistor, the arrangement being such that, in use, the field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable, negative feedback being provided to improve the linearity of the network.

Claim 17

An electrical network having two terminals wherein: first resistance means, second resistance means, the source-drain path of a first field effect transistor and third resistance means are connected in the order stated from one terminal to the other, the collector of a bipolar transistor an the gate of a second field effect transistor are connected to the junction of the first and second resistance means, the gate of the first field effect transistor is connected to the said one terminal, the source-drain path of the second field effect transistor is connected from the junction of the source-drain path of the first field effect transistor and the third resistance means to the base of the bipolar transistor, and the emitter of the bipolar transistor is connected to the said other terminal, the arrangement being such that, in use, the second field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable, the first resistance means and first field effect transistor co-operating to provide negative feed back to improve the linearity of the network.

Claim 18

An electrical network having two terminals wherein: first resistance means, second resistance means, the source-drain path of a first field effect transistor and third resistance means are connected in the order stated from one terminal to the other, the collector of a bipolar transistor an the gate of a second field effect transistor are connected to the junction of the first and second resistance means, the gate of the first field effect transistor is connected to the said one terminal, the source-drain path of the second field effect transistor is connected from the junction of the source-drain path of the first field effect transistor and the third resistance means to the base of the bipolar transistor, and the emitter of the bipolar transistor is connected to the said other terminal, the arrangement being such that, in use, the second field effect transistor controls the bias of the bipolar transistor whereby the voltage/current characteristic of the network contains a region in which increase in one of the variables voltage or current causes a decrease in the other variable, the first resistance means and first field effect transistor co-operating to provide negative feed back to improve the linearity of the network.