Binary full adder circuit

Claim 2

A combinatorial circuit including a plurality of electrical transmission switches having a first and a second currentconducting terminal and a control terminal for effecting either a closed or an open circuit between said first and second current conducting terminals, comprising in combination: a first set of three input terminals for receiving respectively inputs representative of an augend signal A, an addend signal B and an input carry signal C; a second set of three input terminals for receiving respectively inputs representative of the complement signals A, B, and C of said augend, said addend and said input carry signals; a first electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to the augend signal A input terminal and the current control terminal to the complement B signal input terminal, being operable to provide the logic function AB at the second current-conducting terminal; a second electrical transmission switch including circuit means connecting the first current conducting terminal thereof to the complement A signal input terminal and the current control terminal to the addend signal B input terminal and providing the logic function AB at the second current-conducting terminal; circuit means connecting the second current conducting terminal of said first and second switch at a first circuit junction and providing a signal having the logical function AB+AB thereat; a third electrical transmission switch including circuit means coupling said first current-conducting terminal thereof to said first circuit junction and the current control terminal to the complement C signal input terminal, and being operable to provide an output signal of the logic function C(AB+AB) at the second current-conducting terminal thereof; a sum signal S output terminal including circuit means coupling said output terminal to said second current terminal of said third transmission switch; a fourth electrical transmIssion switch including circuit means connecting the first current conducting terminal thereof to the augend signal A input terminal and the current control terminal to the addend signal B input terminal, being operable to provide the logic function AB at the second current-conducting terminal a fifth electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to the complement A signal input terminal and the control terminal to the complement B signal input terminal being operable to provide the logic function AB at the second current-conducting terminal; circuit means connecting the second current-conducting terminal of said fourth and fifth transmission switch at a second circuit junction and providing a signal of the logic function AB+AB; a sixth electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to said second circuit junction and the control terminal to the input carry signal C input signal, being operable to provide an output signal at the second current-conducting terminal of the logic function C(AB+AB); and circuit means connecting said second current-conducting terminals of said sixth transmission switch to said sum signal S output terminal.

Claim 3

The invention as defined by claim 1 wherein said plurality of electrical transmission switches are comprised of semiconductor switch means.

Claim 4

The invention as defined by claim 1 wherein said plurality of electrical transmission switch means are comprised of field effect transistors having source, drain and gate electrodes and wherein said first and second current conducting terminals are respectively common to either of said source and drain electrodes and said control terminal is common to said gate electrode.

Claim 5

The invention as defined by claim 3 wherein said field effect transistors are comprised of metal oxide semiconductor field effect transistors of like semiconductivity.

Claim 6

The invention as defined by claim 1 wherein said plurality of transmission switches are each comprised of at least one pair of complementary MOSFETs having source, drain and gate electrodes including circuit means coupling respective drain and source electrodes in parallel and wherein said first and second current conducting terminals respectively comprise said source and drain electrodes and said gate electrode of one of said complementary pair comprises said control terminal.

Claim 7

The invention as defined by claim 5 and additionally including signal inverter means coupled between the gate electrodes of said at least one pair of complementary MOSFETs.

Claim 8

The invention as defined by claim 6 wherein said signal inverter means comprises a second pair of complementary MOSFETs, each having source, drain and gate electrodes, and including circuit means commonly coupling the gate electrodes thereof to said gate electrode of said one MOSFET of said at least one pair, circuit means commonly connecting the drain electrodes to the gate electrode of the other MOSFET of said at least one pair, and circuit means coupling said source electrodes of said second complementary pair of MOSFETs across a bias potential.

Claim 9

The invention as defined by claim 1 and additionally including: an output carry signal K output terminal; a seventh electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to the input carry signal C input terminal, circuit means connecting the control terminal thereof to said first circuit junction and circuit means connecting the second current conducting terminal to said output carry signal K output terminal; a third set of two input terminals for receiving respectively inputs representative of a first and a second steady state logic level; an eighth electrical transmission switch including circuit meaNs connecting the first current--conducting terminal thereof to the complement A of the augend input signal input terminal and circuit means connecting the control terminal to the complement B of the addend input signal input terminal and being operable to provide the logic function AB at the second current-conducting terminal; a ninth electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to one input terminal of said third set of input terminals and circuit means connecting the control terminal to the addend signal B input terminal; a 10 electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to said one terminal of said third set of input terminals and circuit means connecting the control terminal commonly to the second current-conducting terminal of said eighth and ninth electrical transmission switches, said eighth, ninth and 10 electrical transmission switches being operable to gate said first steady state logic level to said second output terminal for two of eight possible combinations of augend, addend and input carry signals; an 11 electrical transmission switch including circuit means connecting the first current-conducting input terminal thereof to the augend signal A input terminal and circuit means connecting the control terminal to the addend signal B input terminal and being operable to provide the logic function AB at the second current--conducting terminal; a 12 electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to said one input terminal of said third set of input terminals and circuit means connecting the control terminal to the complement B of the addend input signal input terminal; a 13 electrical transmission switch including circuit means connecting the first current-conducting terminal thereof to the second input terminal of said third set of input terminals, and circuit means commonly connecting the current control terminal thereof to he second current-conducting terminal of said 11 and 12 electrical transmission switches, said 11, 12 and 13 electrical transmission switches being operable to gate said steady state signal of said second steady state logic level to said output carry signal K output terminal for two other combinations of augend, addend and input carry signals; and circuit means commonly connecting the second current-conducting terminal of said 10 and 13 electrical transmission switches to said output carry signal K output terminal, and providing an output having the characteristic logic equation K AB+C(AB+AB) for the eight possible combinations of augend, addend and input carry signals.

Claim 10

The invention as defined by claim 8 wherein said plurality of electrical transmission switches are comprised of semiconductor switches.

Claim 11

The invention as defined by claim 8 wherein said plurality of electrical transmission switches are comprised of field effect transistors having source, drain and gate electrodes and wherein said first and second current-conducting terminals are respectively common to either of said source and drain electrodes and said control terminal is common to said gate electrode.

Claim 12

The invention as defined by claim 10 wherein said field effect transistors are comprised of insulated gate field effect transistors.

Claim 13

The invention as defined by claim 8 wherein all said electrical transmission switches are comprised of at least one pair of complementary MOSFETs each having drain, source and gate electrodes and including circuit means coupling respective drain and source electrodes in parallel and wherein said drains define said first current-conducting terminal, the sources define said second current-conducting terminal and the gate electrode of At least one of said one pair of complementary MOSFETs defines said control terminal.

Claim 14

The invention as defined by claim 12 and additionally including a signal inverter circuit, comprising a second pair of complementary MOSFETs, coupled between the gate electrodes of said at least one pair of complementary MOSFETs.

Claim 15

An arithmetic circuit for producing a binary output carry signal K comprising in combination: a first set of five input terminals (52), (54), (56), (58) and (69) having input signals respectively applied thereto representative of a binary augend signal A, its complement A, a binary addend signal B, its complement B and a binary input carry signal C; a second set of two input terminals (60) and (62) having steady state signals applied thereto representative of a ''''0'''' binary logic state and a ''''1'''' binary logic state respectively; a plurality of electrical transmission switches having first and second current-conducting terminals and a control terminal for effecting an open and closed current-conducting path between said first and second current conducting terminals upon the application of a control signal thereto, said plurality comprising: a first and second electrical transmission switch (64) and (66) each including circuit means connecting respective first current-conducting terminals thereof to the augend signal A input terminal (52) and the complement A input terminal (54), circuit means connecting respective control terminals to the complement B of the addend signal input terminal (58) and the addend signal B input terminal (56) and circuit means commonly coupling the second current-conducting terminal of said first and second transmission switch at a first junction (67) and providing a binary signal thereat of the logical function (AB+AB); an output terminal (70) adapted to provide the carry output signal K thereat; a third electrical transmission switch (68) including circuit means connecting the first current-conducting terminal thereof to the input carry signal C input terminal (69), circuit means connecting the control terminal to said first junction (67) and circuit means connecting the second current-conducting terminal to said output terminal (70) and providing the logical function C(AB+AB) for four of eight possible combinations of input signals; a fourth electrical transmission switch (76) including circuit means connecting the first current-conducting terminal thereof to the complement A of the augend signal input terminal (54) and circuit means connecting the control terminal to the complement B of the signal input terminal (58); a fifth electrical transmission switch (78) including circuit means connecting the first current-conducting terminal thereof to one input terminal (60) of said second set of input terminals, and circuit means connecting the control input terminal to the addend signal B input terminal (56); a sixth electrical transmission switch (72) including circuit means connecting the first current-conducting terminal thereof to said one input terminal (60) of said second set of input terminals and circuit means connecting the control terminal commonly to the second current-conducting terminals of said fourth and fifth electrical transmission switches (76) and (78) at a second junction (77), and circuit means connecting the second current-conducting terminal of said sixth transmission switch (72) to said output terminal (70) and gating said steady state ''''0'''' logic state to said output terminal (70) for two other of said eight possible combinations of input signals for providing the logic function AB; a seventh electrical transmission switch (82) including circuit means connecting the first current-conducting terminal thereof to the augend signal A input terminal (52) aNd circuit means connecting the control input terminal to the addend signal B input terminal (56); an eighth electrical transmission switch (80) including circuit means connecting the first current-conducting terminal to said first input terminal (60) of said second set of input terminals and circuit means connecting the control terminal to the complement signal B input terminal (58); and a ninth electrical transmission switch (74) including circuit means connecting the first current conducting terminal thereof to the second input terminal (62) of said second set of input terminals, circuit means commonly connecting the control terminal to the second current-conducting terminals of said seventh and eighth electrical transmission switches (80) and (82) at a third junction (83), and circuit means connecting the second current-conducting terminal of said ninth electrical transmission switch to said output terminal (70) and providing the logic function AB for the remaining two possible combinations of input signals, whereby said output terminal (70) provides a carry out signal K according to the logic equation K AB+C(AB+AB) for said eight possible combinations of input signals.

Claim 16

An arithmetic circuit for producing a binary output carry signal K comprising in combination: a first set of five input terminals (52), (54), (56), (58) and (69) having input signals respectively applied thereto representative of a binary augend signal A, its complement A, a binary addend signal B, its complement B and a binary input carry signal C; a second set of two input terminals (60) and (62) having steady state signals applied thereto representative of a ''''0'''' binary logic state and a ''''1'''' binary logic state respectively; a plurality of electrical transmission switches having first and second current-conducting terminals and a control terminal for effecting an open and closed current-conducting path between said first and second current conducting terminals upon the application of a control signal thereto, said plurality comprising: a first and second electrical transmission switch (64) and (66) each including circuit means connecting respective first current-conducting terminals thereof to the augend signal A input terminal (52) and the complement A input terminal (54), circuit means connecting respective control terminals to the complement B of the addend signal input terminal (58) and the addend signal B input terminal (56) and circuit means commonly coupling the second current-conducting terminal of said first and second transmission switch at a first junction (67) and providing a binary signal thereat of the logical function (AB+AB); an output terminal (70) adapted to provide the carry output signal K thereat; a third electrical transmission switch (68) including circuit means connecting the first current-conducting terminal thereof to the input carry signal C input terminal (69), circuit means connecting the control terminal to said first junction (67) and circuit means connecting the second current-conducting terminal to said output terminal (70) and providing the logical function C(AB+AB) for four of eight possible combinations of input signals; a fourth electrical transmission switch (76) including circuit means connecting the first current-conducting terminal thereof to the complement A of the augend signal input terminal (54) and circuit means connecting the control terminal to the complement B of the signal input terminal (58); a fifth electrical transmission switch (78) including circuit means connecting the first current-conducting terminal thereof to one input terminal (60) of said second set of input terminals, and circuit means connecting the control input terminal to the addend signal B input terminal (56); a sixth electrical transmission switch (72) including circuit means connecting the first current-conducting terminal thereof to said one input terminal (60) of said second set of input terminals and circuit means connecting the control terminal commonly to the second current-conducting terminals of said fourth and fifth electrical transmission switches (76) and (78) at a second junction (77), and circuit means connecting the second current-conducting terminal of said sixth transmission switch (72) to said output terminal (70) and gating said steady state ''''0'''' logic state to said output terminal (70) for two other of said eight possible combinations of input signals for providing the logic function AB; a seventh electrical transmission switch (82) including circuit means connecting the first current-conducting terminal thereof to the augend signal A input terminal (52) aNd circuit means connecting the control input terminal to the addend signal B input terminal (56); an eighth electrical transmission switch (80) including circuit means connecting the first current-conducting terminal to said first input terminal (60) of said second set of input terminals and circuit means connecting the control terminal to the complement signal B input terminal (58); and a ninth electrical transmission switch (74) including circuit means connecting the first current conducting terminal thereof to the second input terminal (62) of said second set of input terminals, circuit means commonly connecting the control terminal to the second current-conducting terminals of said seventh and eighth electrical transmission switches (80) and (82) at a third junction (83), and circuit means connecting the second current-conducting terminal of said ninth electrical transmission switch to said output terminal (70) and providing the logic function AB for the remaining two possible combinations of input signals, whereby said output terminal (70) provides a carry out signal K according to the logic equation K AB+C(AB+AB) for said eight possible combinations of input signals.

Claim 17

The invention as defined by claim 14 wherein all said electrical transmission switches are comprised of semiconductor switches.

Claim 18

The invention as defined by claim 14 wherein all said electrical transmission switches are comprised of field effect transistors having source, drain and gate electrodes and wherein said drain and source electrodes comprise respectively either said first or second current-conducting terminals and said gate electrode comprises the control terminal.

Claim 19

The invention as defined by claim 16 wherein said field effect transistors comprise MOSFETs of the same semiconductivity type.

Claim 20

The invention as defined by claim 14 wherein said electrical transmission switches are comprised of at least one pair of complementary MOSFETs, each having source, drain and gate electrodes, including circuit means coupling respective drain and source electrodes in parallel and thereby defining said first and second current-conducting terminals respectively, wherein the gate electrode of one of said pair of complementary MOSFETs defines said control terminal, and electrical signal inverter means coupled between the above-recited gate electrode and the gate electrode of the other MOSFET of said complementary pair of MOSFETs.

Claim 21

The invention as defined by claim 18 wherein said inverter circuit comprises a second pair of complementary MOSFETs each having source, drain and gate electrodes, and including circuit means commonly connecting the gate electrodes thereof to the gate electrode of one MOSFET of said at least one pair, the drain electrodes commonly to the gate electrode of the other MOSFET of said at least one pair, and the source electrodes thereof across a bias potential.