Patent US5982191A successfully refreshed from Google Patents.
US5982191A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Broadly distributed termination for buses using switched terminator logic
Assignee: Oracle America Inc
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Filing: 1997-06-25
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Granted: 1999-11-09
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Expires: 2017-06-25
Abstract
Abstract A bus line is provided with broadly distributed signal termination by using switched termination logic where the pull up resistance of a driver corresponds to the characteristic impedance of the line and the pull down resistance of the driver corresponds to the number of drivers coupled to the line. Accordingly, signals being transmitted over the bus suffer relatively few reflections thus advantageously producing a shortened signal settling time, thereby increasing the attainable signaling frequency.
Inventors
- 👤 Jonathan E. Starr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:15
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/0264; H04L25/0298; G; G06; G06F; G06F13/00; G06F13/38; G06F13/40; G06F13/4063; G06F13/4068; G06F13/4086; H03; H03K; H03K19/00; H03K19/0005
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
122 words
A driver apparatus for driving a signal onto a line having a characteristic impedance, the line having a number of drivers coupled thereto, the driver apparatus comprising: a pull up circuit, the pull up circuit pulling up a signal on the line, the pull up circuit having a pull up resistance corresponding to the impedance of the line; and a pull down circuit, the pull down circuit pulling down a signal on the line, the pull down circuit having a pull down resistance corresponding to the number of drivers coupled to the line, the pull down resistance being substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 2
Dependent Claim
122 words
A driver apparatus for driving a signal onto a line having a characteristic impedance, the line having a number of drivers coupled thereto, the driver apparatus comprising: a pull up circuit, the pull up circuit pulling up a signal on the line, the pull up circuit having a pull up resistance corresponding to the impedance of the line; and a pull down circuit, the pull down circuit pulling down a signal on the line, the pull down circuit having a pull down resistance corresponding to the number of drivers coupled to the line, the pull down resistance being substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 3
Dependent Claim
19 words
The driver apparatus of claim 1 wherein the pull down circuit includes a parallel combination of two NMOS transistors.
Claim 4
Dependent Claim
21 words
The driver apparatus of claim 1 wherein the pull up resistance is substantially equal to the characteristic impedance of the line.
Claim 5
Dependent Claim
15 words
The driver apparatus of claim 1 wherein the pull up circuit includes a PMOS transistor.
Claim 6
Dependent Claim
15 words
The driver apparatus of claim 1 wherein the pull down circuit includes an NMOS transistor.
Claim 7
Dependent Claim
23 words
The driver apparatus of claim 1 wherein the pull up circuit includes a parallel combination of a PMOS transistor and an NMOS transistor.
Claim 8
Dependent Claim
115 words
A driver system comprising: a line for transmitting a signal, the line having a plurality of ends; and a plurality of drivers coupled to the plurality of ends, each driver including a pull up circuit, the pull up circuit pulling up a signal on the line, the pull up circuit having a pull up resistance being substantially equal to the characteristic impedance of the line; and a pull down circuit, the pull down circuit pulling down a signal on the line, the pull down circuit having a pull down resistance being substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 9
Dependent Claim
115 words
A driver system comprising: a line for transmitting a signal, the line having a plurality of ends; and a plurality of drivers coupled to the plurality of ends, each driver including a pull up circuit, the pull up circuit pulling up a signal on the line, the pull up circuit having a pull up resistance being substantially equal to the characteristic impedance of the line; and a pull down circuit, the pull down circuit pulling down a signal on the line, the pull down circuit having a pull down resistance being substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 10
Dependent Claim
126 words
A driver system comprising: a line for transmitting a signal, the line having a plurality of ends; and a plurality of drivers coupled to the plurality of ends, each driver including a pull up circuit, the pull up circuit pulling up a signal on the line, the pull up circuit having a pull up resistance corresponding to the impedance of the line; and a pull down circuit, the pull down circuit pulling down a signal on the line, the pull down circuit having a pull down resistance corresponding to the number of drivers coupled to the line, the pull down resistance being substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 11
Dependent Claim
126 words
A driver system comprising: a line for transmitting a signal, the line having a plurality of ends; and a plurality of drivers coupled to the plurality of ends, each driver including a pull up circuit, the pull up circuit pulling up a signal on the line, the pull up circuit having a pull up resistance corresponding to the impedance of the line; and a pull down circuit, the pull down circuit pulling down a signal on the line, the pull down circuit having a pull down resistance corresponding to the number of drivers coupled to the line, the pull down resistance being substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 12
Dependent Claim
19 words
The driver system of claim 8 wherein the pull down circuit includes a parallel combination of two NMOS transistors.
Claim 13
Dependent Claim
21 words
The driver system of claim 8 wherein the pull up resistance is substantially equal to the characteristic impedance of the line.
Claim 14
Dependent Claim
15 words
The driver system of claim 8 wherein the pull up circuit includes a PMOS transistor.
Claim 15
Dependent Claim
15 words
The driver system of claim 8 wherein the pull down circuit includes an NMOS transistor.
Claim 16
Dependent Claim
23 words
The driver system of claim 8 wherein the pull up circuit includes a parallel combination of a PMOS transistor and an NMOS transistor.
Claim 17
Dependent Claim
125 words
A driver system comprising: a line for transmitting a signal, the line having a plurality of ends; and a plurality of drivers coupled to the plurality of ends, each driver including a pull up circuit, the pull up circuit pulling up a signal on the line; and, a pull down circuit, the pull down circuit pulling down a signal on the line, wherein one of the pull up circuit and the pull down circuit has a resistance substantially equal to the characteristic impedance of the line and another of the pull up circuit and the pull down circuit has a resistance substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 18
Dependent Claim
125 words
A driver system comprising: a line for transmitting a signal, the line having a plurality of ends; and a plurality of drivers coupled to the plurality of ends, each driver including a pull up circuit, the pull up circuit pulling up a signal on the line; and, a pull down circuit, the pull down circuit pulling down a signal on the line, wherein one of the pull up circuit and the pull down circuit has a resistance substantially equal to the characteristic impedance of the line and another of the pull up circuit and the pull down circuit has a resistance substantially equal to the characteristic impedance of the line divided by the difference of the number of drivers coupled to the line minus one.
Claim 19
Dependent Claim
23 words
The driver system of claim 14 wherein the pull up circuit includes a parallel combination of a PMOS transistor and an NMOS transistor.
Claim 20
Dependent Claim
19 words
The driver system of claim 14 wherein the pull down circuit includes a parallel combination of two NMOS transistors.
Claim 21
Dependent Claim
15 words
The driver system of claim 14 wherein the pull up circuit includes a PMOS transistor.
Claim 22
Dependent Claim
15 words
The driver system of claim 14 wherein the pull down circuit includes an NMOS transistor.
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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) | 2002-11-08 | 2003-05-10 | 2003-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-08 | 2007-05-10 | 2007-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-08 | 2011-05-10 | 2011-11-09 | $7700.00 | Window Closed / Lapsed |