Patent US459915A successfully refreshed from Google Patents.
Patent US3757138A successfully refreshed from Google Patents.
US3757138A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Push pull line driver circuit
Assignee: International Business Machines Corp
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Filing: 1972-05-04
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Granted: 1973-09-04
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Expires: 1992-05-04
Abstract
Abstract A line driver circuit for driving highly capacitive or low impedance loads such as the data and power lines that extend from chip to chip of integrated memory and logic circuits utilized in digital computers, peripheral apparatuses therefor and similar digital equipment. The line driver circuit comprises a current switch direct-current-coupled to a single-ended push-pull output stage. The current switch comprises a pair of transistors having their emitters connected to a current source. The output stage comprises a pair of output transistors with the emitter of one output transistor and the collector of the other transistor connected together and to the output of the circuit. The collectors of the current switch transistors are direct-currentcoupled to the respective bases of the output stage transistors. The line driver circuit further comprises an active feedback network for limiting the amplitude of the downward swing of the potential of the output terminal of the output stage and including a feedback transistor having its emitter connected to the output of the output stage and its collector connected to the collector of one of the current switch transistors.
Inventors
- 👤 H Bhatia
- 👤 D Davis
- 👤 D Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:33
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/01; H03K5/02; G; G11; G11C; G11C5/00
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
249 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, means for limiting the amplitude of the downward swing of the output stage output potential, an active feedback network having one end connected to said output stage output and another end connected to one of said current switch outputs.
Claim 2
Dependent Claim
249 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, means for limiting the amplitude of the downward swing of the output stage output potential, an active feedback network having one end connected to said output stage output and another end connected to one of said current switch outputs.
Claim 3
Dependent Claim
50 words
A line driver circuit as set forth in claim 1 wherein said feedback network comprises a feedback transistor having a collector and an emitter, meaNs connecting said feedback transistor emitter to said output stage output, and means connecting said feedback transistor collector to said one output of said current switch.
Claim 4
Dependent Claim
317 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other of said collectors being connected to the other of said current switch outputs, a pair of load transistors of a conductivity type opposite to that of said current switch transistors, each of said load transistors having a collector connected to a collector of a respective one of said current switch transistors.
Claim 5
Dependent Claim
317 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other of said collectors being connected to the other of said current switch outputs, a pair of load transistors of a conductivity type opposite to that of said current switch transistors, each of said load transistors having a collector connected to a collector of a respective one of said current switch transistors.
Claim 6
Dependent Claim
318 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other of said collectors being connected to the other of said current switch outputs, means for limiting the amplitude of the downward swing of the output stage output potential, an active feedback network having one end cOnnected to said output stage output and another end connected to one of said current switch outputs.
Claim 7
Dependent Claim
318 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other of said collectors being connected to the other of said current switch outputs, means for limiting the amplitude of the downward swing of the output stage output potential, an active feedback network having one end cOnnected to said output stage output and another end connected to one of said current switch outputs.
Claim 8
Dependent Claim
50 words
A line driver circuit as set forth in claim 4 wherein said feedback network comprises a feedback transistor having a collector and an emitter, means connecting said feedback transistor emitter to said output stage output, and means connecting said feedback transistor collector to said one output of said current switch.
Claim 9
Dependent Claim
317 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other ofsaid collectors being connected to the other of said current switch outputs, a pair of load transistors of a conductivity type opposite to that of said current switch transistors, each of of said load transistors having a collector connected to a collector of a respective one of said current switch transistors.
Claim 10
Dependent Claim
317 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other ofsaid collectors being connected to the other of said current switch outputs, a pair of load transistors of a conductivity type opposite to that of said current switch transistors, each of of said load transistors having a collector connected to a collector of a respective one of said current switch transistors.
Claim 11
Dependent Claim
352 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of output transistors each having a collector, a base and an emitter, one of said output stage inputs being connected to one of said bases, the other of said output stage inputs being connected to the other of said bases, a power supply having two supply terminals, one of said output transistors having its collector connected to one of said supply terminals, the other of said output transistors having its emitter connected to the other supply terminals, and means connecting the emitter of said one output transistor and the collector of said other output transistor to said output stage output, means for limiting the amplitude of the downward swing of the output stage output potential, and an active feedback network having one end connected to said output stage output and another end connected to one of said current switch outputs.
Claim 12
Dependent Claim
352 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, and means responsive to an electrical signal at an upper potential level at one of said output stage inputs and to an electrical signal at a lower potential level at the other of said output stage inputs for causing the potential of said output stage output to swing downwardly, and responsive to an electrical signal at a lower potential level at said one output stage input and to an electrical signal at an upper potential level at said other output stage input for causing the potential of said output stage output to swing upwardly, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, a pair of output transistors each having a collector, a base and an emitter, one of said output stage inputs being connected to one of said bases, the other of said output stage inputs being connected to the other of said bases, a power supply having two supply terminals, one of said output transistors having its collector connected to one of said supply terminals, the other of said output transistors having its emitter connected to the other supply terminals, and means connecting the emitter of said one output transistor and the collector of said other output transistor to said output stage output, means for limiting the amplitude of the downward swing of the output stage output potential, and an active feedback network having one end connected to said output stage output and another end connected to one of said current switch outputs.
Claim 13
Dependent Claim
50 words
A line driver circuit as set forth in claim 7 wherein said feedback network comprises a feedback transistor having a collector and an emitter, means connecting said feedback transistor emitter to said output stage output, and means connecting said feedback transistor collector to said one output of said current switch.
Claim 14
Dependent Claim
361 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, said current switch comprising a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other of said collectors being connected to the other of said current switch outputs, said output stage comprising a pair of output transistors each having a collector, a base and an emitter, one of said output stage inputs being connected to one of said bases, the other of said output stage inputs being connected to the other of said bases, a power supply having two supply terminals, one of said output transistors having its collector connected to one of said supply terminals, the other of said output transistors having its emitter connected to the other supply terminals, and means connecting the emitter of said one output transistor and the collector of said other output transistor to said output stage output, and a digital signal source having an output connected to said current switch input to transmit thereto said electrical digital signal at either one of two potential levels, a pair of load transistors of a conductivity type opposite to that of said current switch transistors, each of said load transistors hacing a collector connected to a collector of a respective one of said current switch transistors.
Claim 15
Dependent Claim
361 words
A line driver circuit comprising a current switch including an input adapted to receive an electrical digital signal at either one of two potential levels, and a pair of outputs for transmitting respective electrical digital signals of mutually opposite phase so that the signal transmitted by one output is at one potential level and the signal transmitted by the other output is at another potential level, a single-ended push-pull output stage including a pair of inputs, an output, first means direct-current coupling one of said current switch outputs to a first of said output stage inputs, and second means direct-current coupling the other of said current switch outputs to a second of said output stage inputs, said current switch comprising a pair of transistors each having a collector, a base, and an emitter, a current source connected to said emitters, said current switch input being connected to one of said bases, and bias means connected to the other of said bases, one of said collectors being connected to one of said current switch outputs, the other of said collectors being connected to the other of said current switch outputs, said output stage comprising a pair of output transistors each having a collector, a base and an emitter, one of said output stage inputs being connected to one of said bases, the other of said output stage inputs being connected to the other of said bases, a power supply having two supply terminals, one of said output transistors having its collector connected to one of said supply terminals, the other of said output transistors having its emitter connected to the other supply terminals, and means connecting the emitter of said one output transistor and the collector of said other output transistor to said output stage output, and a digital signal source having an output connected to said current switch input to transmit thereto said electrical digital signal at either one of two potential levels, a pair of load transistors of a conductivity type opposite to that of said current switch transistors, each of said load transistors hacing a collector connected to a collector of a respective one of said current switch transistors.
Claim 16
Dependent Claim
27 words
A line driver circuit as set forth in claim 9 and comprising means for limiting the amplitude of the downward swing of the output stage output potential.
Claim 17
Dependent Claim
39 words
A line driver circuit as set forth in claim 10 wherein said limiting means comprises an active feedback network having one end connected to said output stage output and another end connected to one of said current switch outputs.
Claim 18
Dependent Claim
50 words
A line driver circuit as set forth in claim 11 wherein said feedback network comprises a feedback transistor having a collector and an emitter, means connecting said feedback transistor emitter to said output stage output, and means connecting said feedback transistor collector to said one output of said current switch.
Claim 19
Dependent Claim
24 words
A line driver circuit as set forth in claim 12 and comprising means for limiting the upward swing of said output stage output potential.
Claim 20
Dependent Claim
49 words
A line driver circuit as set forth in claim 13 wherein said last-recited limiting means comprises a clamping diode, a voltage source, means connecting one end of said diode to said voltage source, and means connecting the other end of said diode to one of said current switch outputs.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |