US4825099A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Feedback-controlled current output driver having reduced current surge
Assignee: Visteon Global Technologies Inc
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Filing: 1987-12-04
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Granted: 1989-04-25
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Expires: 2007-12-04
Abstract
Abstract An output pad driver circuit for an integrated circuit chip architecture incorporates a controllably switched current mirror circuit in the circuit path between an output pad driver input terminal to which a digital signal produced by the signal processing circuitry of the chip is applied and an output terminal from which an output signal produced by the output pad is produced. The controllably switched current mirror circuit is coupled to a reference current terminal to which a source of reference current is applied. Coupled between the input terminal and the current mirror circuit is a first switching transistor which controllably causes the controllably switched current mirror circuit to apply a controlled current to the output terminal in response to a prescribed change in the logic level of an input signal that is applied to the input terminal. A second switching transistor is coupled in a feedback path between the output terminal and the current mirror circuit, and causes the current mirror circuit to terminate the supply of controlled current to the output terminal in response to the voltage level at said output terminal reaching a prescribed threshold. A third switching transistor is coupled between the input terminal and the current mirror circuit, so as to prevent the current mirror from applying a controlled current to the output terminal until the state of the input signal undergoes the prescribed logic level change.
Inventors
- 👤 Steven K. Barton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:16
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/16; H03K17/161; H03K17/165; H03K17/166; H03K17/51; H03K17/56; H03K17/687; H03K17/6871; H03K17/6872
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
137 words
A controlled current driver circuit comprising: an input terminal to which an input signal is applied; an output terminal from which an output signal is derived; a reference current terminal to which a source of reference current is applied; a current mirror circuit coupled between said reference current terminal and said output terminal; first means, coupled between said input terminal and said current mirror circuit, for causing said current mirror circuit to apply a controlled current to said output terminal in response to the application of an input signal to said input terminal; and second means, coupled between said output terminal and said current mirror circuit, for causing said current mirror circuit to terminate the supply of controlled current to said output terminal in response to the voltage level at said output terminal reaching a prescribed threshold.
Claim 2
Dependent Claim
137 words
A controlled current driver circuit comprising: an input terminal to which an input signal is applied; an output terminal from which an output signal is derived; a reference current terminal to which a source of reference current is applied; a current mirror circuit coupled between said reference current terminal and said output terminal; first means, coupled between said input terminal and said current mirror circuit, for causing said current mirror circuit to apply a controlled current to said output terminal in response to the application of an input signal to said input terminal; and second means, coupled between said output terminal and said current mirror circuit, for causing said current mirror circuit to terminate the supply of controlled current to said output terminal in response to the voltage level at said output terminal reaching a prescribed threshold.
Claim 3
Dependent Claim
69 words
A controlled current driver circuit according to claim 1, wherein said first means comprises first switching means, responsive to said input signal having a prescribed voltage level, for causing said source of reference current to be coupled to said current mirror circuit and second switching means for preventing said current mirror from applying said controlled current to said output terminal until said input signal reaches said prescribed voltage level.
Claim 4
Dependent Claim
77 words
A controlled current driver circuit according to claim 2, wherein said second means comprises third switching means, coupled between said output terminal and said current mirror circuit, for enabling said current mirror circuit to supply said controlled current to said output terminal in response to said source of reference current being coupled to said current mirror circuit by the operation of said first switching means, until the voltage level at said output terminal reaches said prescribed threshold.
Claim 5
Dependent Claim
115 words
A controlled current driver circuit according to claim 3, wherein said current mirror circuit comprises a first transistor having an input electrode, an output electrode and a control electrode, and a second transistor having an input electrode, an output electrode and a control electrode, the control and output electrodes of said first transistor being coupled to each of said first and second switching means and to the control electrode of said second transistor, the input electrode of said first transistor being coupled to said third switching means, the output electrode of said second transistor being coupled to said output terminal and the input electrode of said second transistor being coupled to a reference potential terminal.
Claim 6
Dependent Claim
49 words
A controlled current driver circuit according to claim 4, wherein said third switching means comprises a third transistor having an input electrode coupled to said reference potential terminal, an output electrode coupled to the input electrode of said first transistor and a control electrode coupled to said output terminal.
Claim 7
Dependent Claim
51 words
A controlled current driver circuit according to claim 5, wherein said second switching means comprises a fourth transistor having an input electrode coupled to said reference potential terminal, an output electrode coupled to the control electrode of said first and second transistors and a control electrode coupled to said input terminal
Claim 8
Dependent Claim
57 words
A controlled current driver circuit according to claim 6, wherein said first switching means comprises a fifth transistor having an input electrode coupled to receive said reference current, an output electrode coupled to the output electrode of said first transistor and the control electrode of said second transistor, and a control electrode coupled to said input terminal.
Claim 9
Dependent Claim
30 words
A controlled current driver circuit according to claim 3, wherein each of said current mirror circuit and said first, second and third switching means is comprised of field effect transistors.
Claim 10
Dependent Claim
19 words
A controlled current driver circuit according to claim 7, wherein each of said transistors is a field effect transistor.
Claim 11
Dependent Claim
150 words
A controlled current driver circuit comprising: an input terminal to which an input signal, the state of which varies between first and second voltage levels, is applied; an output terminal from which an output signal is derived; a reference current terminal to which a source of reference current is applied; a current mirror circuit coupled between said reference current terminal and said output terminal; first means, coupled between said input terminal and said current mirror circuit, for causing said current mirror circuit to apply a controlled current to said output terminal in response to the state of said input signal being at said first voltage level; and second means, coupled between said output terminal and said current mirror circuit, for causing said current mirror circuit to terminate the supply of controlled current to said output terminal in response to the voltage level at said output terminal reaching a prescribed threshold.
Claim 12
Dependent Claim
150 words
A controlled current driver circuit comprising: an input terminal to which an input signal, the state of which varies between first and second voltage levels, is applied; an output terminal from which an output signal is derived; a reference current terminal to which a source of reference current is applied; a current mirror circuit coupled between said reference current terminal and said output terminal; first means, coupled between said input terminal and said current mirror circuit, for causing said current mirror circuit to apply a controlled current to said output terminal in response to the state of said input signal being at said first voltage level; and second means, coupled between said output terminal and said current mirror circuit, for causing said current mirror circuit to terminate the supply of controlled current to said output terminal in response to the voltage level at said output terminal reaching a prescribed threshold.
Claim 13
Dependent Claim
76 words
A controlled current driver circuit according to claim 10, wherein said first means comprises first switching means, responsive to the state of said input signal being at said first voltage level, for causing said source of reference current to be coupled to said current mirror circuit, and second switching means for preventing said current mirror from applying said controlled current to said output terminal until the state of said input signal reaches said first voltage level.
Claim 14
Dependent Claim
77 words
A controlled current driver circuit according to claim 11, wherein said second means comprises third switching means, coupled between said output terminal and said current mirror circuit, for enabling said current mirror circuit to supply said controlled current to said output terminal in response to said source of reference current being coupled to said current mirror circuit by the operation of said first switching means, until the voltage level at said output terminal reaches said prescribed threshold.
Claim 15
Dependent Claim
115 words
A controlled current driver circuit according to claim 12, wherein said current mirror circuit comprises a first transistor having an input electrode, an output electrode and a control electrode, and a second transistor having an input electrode, an output electrode and a control electrode, the control and output electrodes of said first transistor being coupled to each of said first and second switching means and to the control electrode of said second transistor, the input electrode of said first transistor being coupled t said third switching means, the output electrode of said second transistor being coupled to said output terminal and the input electrode of said second transistor being coupled to a reference potential terminal.
Claim 16
Dependent Claim
49 words
A controlled current driver circuit according to claim 13, wherein said third switching means comprises a third transistor having an input electrode coupled to said reference potential terminal, an output electrode coupled to the input electrode of said first transistor and a control electrode coupled to said output terminal.
Claim 17
Dependent Claim
51 words
A controlled current driver circuit according to claim 14, wherein said second switching means comprises a fourth transistor having an input electrode coupled to said reference potential terminal, an output electrode coupled to the control electrode of said first and second transistors and a control electrode coupled to said input terminal.
Claim 18
Dependent Claim
57 words
A controlled current driver circuit according to claim 15, wherein said first switching means comprises a fifth transistor having an input electrode coupled to receive said reference current, an output electrode coupled to the output electrode of said first transistor and the control electrode of said second transistor, and a control electrode coupled to said input terminal.
Claim 19
Dependent Claim
30 words
A controlled current driver circuit according to claim 12, wherein each of said current mirror circuit and said first, second and third switching means is comprised of field effect transistors.
Claim 20
Dependent Claim
19 words
A controlled current driver circuit according to claim 16, wherein each of said transistors is a field effect transistor.
Claim 21
Dependent Claim
171 words
A controlled current driver comprising: an input terminal to which an input signal, the state of which varies between first and second voltage levels, is applied; an output terminal from which an output signal is derived; and a pair of complementary output current driver circuits coupled between said input terminal and said output terminal, each of which comprises a reference current terminal to which a source of reference current is applied, a current mirror circuit coupled between said reference current terminal and said output terminal, first means, coupled between said input terminal and said current mirror circuit, for causing said current mirror circuit to apply a controlled current to said output terminal in response to the state of said input signal being at said first voltage level, and second means, coupled between said output terminal and said current mirror circuit, for causing said current mirror circuit to terminate the supply of controlled current to said output terminal in response to the voltage level at said output terminal reaching a prescribed threshold.
Claim 22
Dependent Claim
171 words
A controlled current driver comprising: an input terminal to which an input signal, the state of which varies between first and second voltage levels, is applied; an output terminal from which an output signal is derived; and a pair of complementary output current driver circuits coupled between said input terminal and said output terminal, each of which comprises a reference current terminal to which a source of reference current is applied, a current mirror circuit coupled between said reference current terminal and said output terminal, first means, coupled between said input terminal and said current mirror circuit, for causing said current mirror circuit to apply a controlled current to said output terminal in response to the state of said input signal being at said first voltage level, and second means, coupled between said output terminal and said current mirror circuit, for causing said current mirror circuit to terminate the supply of controlled current to said output terminal in response to the voltage level at said output terminal reaching a prescribed threshold.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-24 | 1992-10-24 | 1993-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-24 | 1996-10-24 | 1997-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-24 | 2000-10-24 | 2001-04-25 | $7700.00 | Window Closed / Lapsed |