Four-quadrant multiplier circuit

Claim 2

A circuit for providing four-quadrant multiplier operation comprising: a pair of control devices each respectively provided with an output terminal, a control terminal, and a common terminal, said common terminals being coupled together, a pair of input devices coupled respectively to said control terminals and receivIng complementary input currents for providing thereacross the input applied to each said control device, said input devices having logarithmic characteristics substantially matching those of the pair of control devices for producing a linear output at said output terminals, a second pair of control devices each respectively provided with an output terminal, a control terminal, and a common terminal, the last mentioned common terminals being coupled together, means also coupling the input devices respectively to the control terminals of the second pair of control devices, and means cross-connecting the output terminals of the first and second pairs of control devices.

Claim 3

A circuit for providing four-quadrant multiplier operation comprising: a pair of control devices each respectively provided with an output terminal, a control terminal, and a common terminal, said common terminals being coupled together, a pair of input devices coupled respectively to said control terminals and receiving complementary input currents for providing thereacross the input applied to each said control device, said input devices having logarithmic characteristics substantially matching those of the pair of control devices for producing a linear output at said output terminals, a second pair of control devices each respectively provided with an output terminal, a control terminal, and a common terminal, the last mentioned common terminals being coupled together, the control terminals of the second pair of control devices also receiving inputs logarithmically related to the input currents, and means cross-connecting the output terminals of the first and second pairs of control devices.

Claim 4

A circuit for providing four-quadrant multiplier operation comprising: a pair of control devices each respectively provided with an output terminal, a control terminal, and a common terminal, said common terminals being coupled together, a pair of input devices coupled respectively to said control terminals and receiving complementary input currents for providing thereacross the input applied to each said control device, said input devices having logarithmic characteristics substantially matching those of the pair of control devices for producing a linear output at said output terminals, a second pair of control devices each respectively provided with an output terminal, a control terminal, and a common terminal, the last mentioned common terminals being coupled together, the control terminals of the second pair of control devices also receiving inputs logarithmically related to the input currents, and means cross-connecting the output terminals of the first and second pairs of control devices.

Claim 5

The amplifier circuit according to claim 2 wherein said control devices and said input devices comprise semiconductor junctions having substantially the same logarithmic characteristics.

Claim 6

A differential amplifier circuit for providing four-quadrant multiplier operation comprising: a first differential amplifier for receiving a first value to be multiplied and producing differential outputs, a first pair of control devices respectively provided with an output terminal, a control terminal, and a common terminal, said common terminals being coupled together and to a first output terminal of said first differential amplifier, a second pair of control devices respectively provided with an output terminal, a control terminal, and a common terminal, said last mentioned common terminals being coupled together and to a second output terminal of said first differential amplifier, a second differential amplifier for receiving a second value to be multiplied and producing differential outputs, means coupling a first output of said second differential amplifier to control terminals of a first control device of said first pair and a first control device of said second pair of control devices, means coupling a second output of said second differential amplifier to control terminals of a second control device of said first pair and a second control device of said second pair of control devices, a pair of input devices coupled respectively to output terminals of said second differential amplifier for providing across said input devices the input applied to said first and second pairs of control devices, said input devices each having a logarithmic characteristic substantially matching that of the first and second pair of control devices, means coupling together the output terminals of the first of said first pair of control devices and the second of the second pair of control devices, and means coupling together the output terminals of the second of the first pair of control devices and the first of the second pair of control devices.

Claim 7

A differential amplifier circuit for providing four-quadrant multiplier operation comprising: a first differential amplifier for receiving a first value to be multiplied and producing differential outputs, a first pair of control devices respectively provided with an output terminal, a control terminal, and a common terminal, said common terminals being coupled together and to a first output terminal of said first differential amplifier, a second pair of control devices respectively provided with an output terminal, a control terminal, and a common terminal, said last mentioned common terminals being coupled together and to a second output terminal of said first differential amplifier, a second differential amplifier for receiving a second value to be multiplied and producing differential outputs, means coupling a first output of said second differential amplifier to control terminals of a first control device of said first pair and a first control device of said second pair of control devices, means coupling a second output of said second differential amplifier to control terminals of a second control device of said first pair and a second control device of said second pair of control devices, a pair of input devices coupled respectively to output terminals of said second differential amplifier for providing across said input devices the input applied to said first and second pairs of control devices, said input devices each having a logarithmic characteristic substantially matching that of the first and second pair of control devices, means coupling together the output terminals of the first of said first pair of control devices and the second of the second pair of control devices, and means coupling together the output terminals of the second of the first pair of control devices and the first of the second pair of control devices.

Claim 8

A four-quadrant multiplier circuit comprising: two pairs of control devices wherein each pair is differentially connected to provide differential outputs in response to differentiaL control inputs applied to such pair, each pair having a common current supply terminal and separate control inputs, and each device thereof having a non-linear output versus control input characteristic for accomplishing multiplication, means for differentially applying currents representing a first value to be multiplied between the common current supply terminals of said pairs of control devices, means for differentially applying voltages representing a second value to be multiplied between control inputs of each said pair of control devices, said means for applying said voltages comprising means for receiving input currents representative of said second value and for producing voltages thereacross non-linearly related to said input currents by a characteristic which substantially compensates for said first mentioned characteristic to linearize the effect of said second value on the multiplier circuit output, and means coupling differential outputs of said pairs of differential devices in an opposed phase sense relative to the control inputs applied thereto to provide an output for said multiplier circuit.

Claim 9

A four-quadrant multiplier circuit comprising: two pairs of control devices wherein each pair is differentially connected to provide differential outputs in response to differentiaL control inputs applied to such pair, each pair having a common current supply terminal and separate control inputs, and each device thereof having a non-linear output versus control input characteristic for accomplishing multiplication, means for differentially applying currents representing a first value to be multiplied between the common current supply terminals of said pairs of control devices, means for differentially applying voltages representing a second value to be multiplied between control inputs of each said pair of control devices, said means for applying said voltages comprising means for receiving input currents representative of said second value and for producing voltages thereacross non-linearly related to said input currents by a characteristic which substantially compensates for said first mentioned characteristic to linearize the effect of said second value on the multiplier circuit output, and means coupling differential outputs of said pairs of differential devices in an opposed phase sense relative to the control inputs applied thereto to provide an output for said multiplier circuit.

Claim 10

A four-quadrant multiplier comprising: two pairs of circuits with each pair connected in differential relation, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current for providing a multiplying action, each circuit having a current input terminal, a current output terminal, and a common terminal, a first current terminal coupled to common terminals of a first differential pair of said circuits and a second current terminal coupled to common terminals of a second differential pair of said circuits, said current terminals differentially applying a first factor to be multiplied, means for applying a current value representative of the second factor to be multiplied between input terminals of the circuits of each differential pair, and means for coupling the output terminals of the differential pairs of circuits in an opposed phase sense relative to the input terminals of said pairs.

Claim 11

A four-quadrant multiplier comprising: two pairs of circuits with each pair connected in differential relation, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current for providing a multiplying action, each circuit having a current input terminal, a current output terminal, and a common terminal, a first current terminal coupled to common terminals of a first differential pair of said circuits and a second current terminal coupled to common terminals of a second differential pair of said circuits, said current terminals differentially applying a first factor to be multiplied, means for applying a current value representative of the second factor to be multiplied between input terminals of the circuits of each differential pair, and means for coupling the output terminals of the differential pairs of circuits in an opposed phase sense relative to the input terminals of said pairs.

Claim 12

The multiplier according to claim 6 wherein each said circuit comprises a transistor having a semiconductor junction coupled between the base and emitter terminals thereof.

Claim 13

The multiplier according to claim 6 wherein each said circuit comprises a first transistor connected to provide an output current, a semiconductor junction device substantially through which said output current flows, a second transistor having an output terminal and a control terminal, wherein said control terminal is coupled to said semiconductor junction device so that the current in said second transistor is modified in response to the voltage across said semiconductor junction device, and means coupling the output from the output terminal of said second transistor to control said first transistor.

Claim 14

The multiplier according to claim 6 further including an additional differential pair of circuits, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current, each circuit having a current input terminal, a current output terminal, and a common terminal, and means coupling the output terminals of said further pair of circuits to said first and second current terminals.

Claim 15

A four-quadrant multiplier comprising: two pairs of circuits with each pair connected in differential relation, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current for providing a multiplying action, each circuit having a current input terminal, a current output terminal, and a common terminal, wherein the common terminals of the circuiTs comprising each pair are coupled together, means for differentially driving input terminals of each differential pair with current representative of a first factor to be multiplied, means for differentially driving the coupled common terminals of said pairs with current representative of a second factor to be multiplied, and means for deriving a product output from said differential pairs in an out of phase sense from each pair relative to the differential inputs thereof.

Claim 16

A four-quadrant multiplier comprising: two pairs of circuits with each pair connected in differential relation, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current for providing a multiplying action, each circuit having a current input terminal, a current output terminal, and a common terminal, wherein the common terminals of the circuiTs comprising each pair are coupled together, means for differentially driving input terminals of each differential pair with current representative of a first factor to be multiplied, means for differentially driving the coupled common terminals of said pairs with current representative of a second factor to be multiplied, and means for deriving a product output from said differential pairs in an out of phase sense from each pair relative to the differential inputs thereof.

Claim 17

A multiplier comprising a pair of circuits connected in differential relation, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current for providing a multiplying action, each circuit having a current input terminal, a current output terminal, and a common terminal, means for providing a current to said common terminals of said circuits representative of a first factor to be multiplied, and means for applying an input to said input terminals of said pair of circuits representative of a second factor to be multiplied.

Claim 18

A multiplier comprising a pair of circuits connected in differential relation, each circuit providing an output current linearly proportional to input current while being characterized by a logarithmic operating characteristic relating voltage in said circuit to input current for providing a multiplying action, each circuit having a current input terminal, a current output terminal, and a common terminal, means for providing a current to said common terminals of said circuits representative of a first factor to be multiplied, and means for applying an input to said input terminals of said pair of circuits representative of a second factor to be multiplied.