Patent EP0254011A2 successfully refreshed from Google Patents.
EP0254011A2
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Adjustable impedance driver network
Assignee: Credence Systems Corp
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Filing: 1987-06-11
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Granted: —
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Expires: 2007-06-11
Abstract
Abstract A variable impedance driver network comprises a plurality of transmission gates connected in parallel between a voltage source and an output. Each transmission gate has a predetermined nominal impedance and by turning on selective gates the overall impedance of the network may be adjusted to match that required at the output.
Inventors
- 👤 Steven Kent Sullivan
- 👤 Christopher Warren Branson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 06:24
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/687; H03K17/693; H03K19/00; H03K19/0005
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
67 words
An adjustable impedance driver network for coupling a voltage source to an output comprising a plurality of selectively operable gates connected in parallel between said voltage source and said output, each of said gates having a predetermined nominal impedance whereby one or more of said gates may be actuated by a control signal to provide an adjustable impedance circuit path between said voltage source and said output.
Claim 2
Dependent Claim
67 words
An adjustable impedance driver network for coupling a voltage source to an output comprising a plurality of selectively operable gates connected in parallel between said voltage source and said output, each of said gates having a predetermined nominal impedance whereby one or more of said gates may be actuated by a control signal to provide an adjustable impedance circuit path between said voltage source and said output.
Claim 3
Dependent Claim
18 words
The adjustable impedance driver network of claim l wherein each of said gates comprises a CMOS transmission gate.
Claim 4
Dependent Claim
30 words
The adjustable impedance network of claim l wherein said control signal comprises a digital code wherein each bit of said digital code controls the actuation of one of said gates.
Claim 5
Dependent Claim
23 words
The adjustable impedance network of claim l wherein said gates have predetermined nominal impedances whose values are R, 2R, ...2 n R, respectively.
Claim 6
Dependent Claim
45 words
An adjustable impedance network comprising a plurality of parallel gates, each of said gates having a predetermined nominal impedance wherein each of said gates is selectively operable to provide a signal path when turned on and to provide a substantially infinite impedance when turned off.
Claim 7
Dependent Claim
45 words
An adjustable impedance network comprising a plurality of parallel gates, each of said gates having a predetermined nominal impedance wherein each of said gates is selectively operable to provide a signal path when turned on and to provide a substantially infinite impedance when turned off.
Claim 8
Dependent Claim
31 words
The adjustable impedance network of claim 5 wherein each of said gates is a CMOS field effect transistor comprising an N channel transistor connected in parallel with a P channel transistor.
Claim 9
Dependent Claim
25 words
The adjustable impedance driver network of claim 5 wherein said network is connected between a voltage source and a transmission line having a predetermined impedance.
Claim 10
Dependent Claim
22 words
The adjustable impedance driver of claim 5 wherein the predetermined nominal impedances of said gates are R, 2R, ...2 n R, respectively.
Claim 11
Dependent Claim
87 words
A driver circuit having a high voltage output state and a low voltage output state and having a variable output impedance comprising: (a) a first plurality of transmission gates connected in parallel between a high voltage source and a transmission line; (b) a second plurality of transmission gates connected between a low voltage source and said transmission line; and (c) each of said pluralities or transmission gates having an adjustable impedance selectively controlled by actuating one or more of said transmission gates in each of said pluralities.
Claim 12
Dependent Claim
87 words
A driver circuit having a high voltage output state and a low voltage output state and having a variable output impedance comprising: (a) a first plurality of transmission gates connected in parallel between a high voltage source and a transmission line; (b) a second plurality of transmission gates connected between a low voltage source and said transmission line; and (c) each of said pluralities or transmission gates having an adjustable impedance selectively controlled by actuating one or more of said transmission gates in each of said pluralities.
Claim 13
Dependent Claim
21 words
l0. The driver circuit of claim 9 wherein each transmission gate in each of said pluralities has a predetermined nominal impedance.
Claim 14
Dependent Claim
29 words
The driver circuit of claim l0 wherein in each of said pluralities of transmission gates, the individual transmission gates have nominal impedances of R, 2R, ...2 n R, respectively.
Claim 15
Dependent Claim
15 words
The driver circuit of claim ll wherein the transmission gates are CMOS field effect transistors.
References Cited (Backward Citations)
No citation records indexed.
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