US 5,265,044 A · High speed arithmetic and logic generator with reduced complexity using negative resistance

Abstract

A technique for generating a carry, AND, OR, NAND, NOR, INVERTING logic and sum and carry: operation in a one or at most two device delay by employing negative differential resistance devices. Circuits implemented with this technique are not only extremely fast, but use a small number of active devices as well. This technique could be implemented in building circuits using any transistor Bipolar Transistors, Field Effect Transistors (FETs), High Electron Mobility Transistors (HEMTs), Hetero-junction Bipolar Transistors (HBTs), etc. The negative differential resistance characteristics of the resonant tunneling transistor can be exploited to increase the noise margin. Resonant tunneling devices have the added advantage of working at very high speeds, and could yield propagation delays less than 5ps.

Claims43

Dependent claims

A carry signal generating device for generating a carry signal, said carry signal generating device has three inputs, said carry signal generating device further comprising:

means for setting a predetermined load line;
a carry signal indicator, including at least three negative differential resistance devices, for identifying said three inputs, wherein each of said at least three negative differential resistance devices has a control terminal to receive one of said inputs and an output terminal to provide an output in response to an input at said control terminal;
and
a common output terminal for generating said carry signal, said common output terminal being coupled to each of said output terminal of said three negative differential resistance devices and said load line setting means.

1 more element

A sum signal generating device for generating a sum signal, said sum signal generating device has five inputs, said sum signal generating device further comprising:

means for setting a predetermined load line;
a sum signal indicator, including five negative differential devices, for identifying said five inputs, each of said five negative differential resistance devices has a control terminal to receive one of said five inputs and an output terminal to provide an output in response to an input of said control terminal;
and
a common output terminal for generating said sum signal, wherein said common output terminal is coupled to each of five outputs of said five negative differential resistance devices and said load line setting means.

1 more element

A device for generating a carry signal, said carry signal generating device has three inputs, said carry signal generating device further comprising:

means for setting a predetermined load line;
a carry signal indicator, including at least three negative differential resistance devices, for identifying said at least three inputs, wherein each of said at least three negative differential resistance devices has a control terminal to receive one of said inputs and an output terminal to provide a conducting current in response to a first logic state input at said control terminal;
and
a common output terminal coupled to each of at least three output terminals of said at least three negative differential resistance devices and said load line setting means, so that said common output terminal generates different magnitudes of conducting currents according to negative differential resistance I-V characteristic current curves in response to different numbers of said first logical state inputs at said at least three control terminals, whereby an operating point voltage at said common output terminal is determined by one of said negative differential resistance I-V characteristic current curves selected by said load line setting means in response to a number of said first logical state inputs at said at least three control terminals, whereby said carry signal is generated by properly setting conducting current magnitude for each of at least three said negative differential resistance devices in terms of their negative differential resistance I-V characteristics and by properly setting said load line.

1 more element

A device for inverting an input having a first logical state and a second logical state, comprising:

means for setting a predetermined load line;
and
a logical state indicator, including a first negative differential resistance device and a second negative differential resistance device, each of said first negative differential resistance device and second negative differential resistance device has an input terminal and output terminal with said first input terminal being coupled to a predetermined voltage level representing said first logic state and said second input terminal receiving said input, wherein each of output terminals provides a conducting current in response to a first logic state input;
and
a common output terminal coupled to each of two output terminals of the first and second negative differential resistance devices and said load line setting means, so that said common output terminal generates two different magnitudes of conducting currents according to negative differential resistance I-V characteristic current curves in response to said first logical state and second logical state of said input, whereby inverted first logic state of said input at said common output terminal is determined by one of said negative differential resistance I-V characteristic current curves in response to said first logical state of said input, selected by said load line setting means, and inverted second logic state of said input at said common output terminal is determined by another one of said negative differential resistance I-V characteristic current curves selected by said load line setting means in response to said second logical state of said input, whereby said inverted logical state of said input is generated by properly setting conducting current magnitudes for said first and second negative differential resistance devices in terms of their negative differential resistance I-V characteristic current curves and by properly setting said load line.

2 more elements

A device for generating a logical output in response to at least two inputs, comprising:

means for setting a predetermined load line;
a logical output indicator, including at least two negative differential resistance devices, for identifying said at least two inputs, wherein each of said at least two negative differential resistance devices has a control terminal to receive one of said at least two inputs and an output terminal to provide a conducting current in response to a first logic state input at said control terminal;
and
a common output terminal coupled to each of output terminals of said at least two negative differential resistance devices and said load line setting means, so that said common output terminal generates different magnitudes of conducting currents according to negative differential resistance I-V characteristic current curves in response to a different number of said first logic state inputs at said at least two control terminals, whereby an operating point voltage at said common output terminal is determined by one of said negative differential resistance I-V characteristic current curves selected by said load line setting means in response to a number of said first logic state inputs at said at least two control terminals, whereby different desired logical outputs are generated by properly setting conducting current for each of said at least two negative differential resistance devices in terms of their negative differential resistance I-V characteristics and by properly setting said load line.

1 more element

Dependencies are inferred from the claim text.

High speed arithmetic and logic generator with reduced complexity using negative resistance

Life of this patent

High speed arithmetic and logic generator with reduced complexity using negative resistance

Life of this patent

Abstract

Claims43