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US5057708A Expired / Lapsed US ⏱️ 0.0 years remaining

Duplex system having a function to suppress radio wave radiation

Assignee: Fujitsu Ltd
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Filing: 1990-06-15
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Granted: 1991-10-15
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Expires: 2010-06-15
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Abstract

Abstract Disclosed is a duplex system having a function to suppress radio wave radiation. To suppress unnecessary radiation of radio waves from duplex clock signal lines, the system comprises a plurality of cards each for mounting electronic devices, a backboard for supporting the plurality of cards to be standing closely together in parallel, a first and a second clock signal sources for respectively generating a first and a second clock signals, a first and a second selecting gates for alternatively selecting one of the first and second clock signals to be output, and a first and a second group of clock signal lines, the clock signal lines in the first and second group respectively being wired closely in parallel on the backboard and wired on the cards, for respectively conducting the first and second clock signals to the cards.

Inventors

  • 👤 Masateru Tagami
  • 👤 Hirokazu Deguchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 13:45
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/003; H03K19/00346; G; G06; G06F; G06F1/00; G06F1/16; G06F1/18; G06F1/181; G06F1/182; H05; H05K; H05K9/00

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 145 words
A duplex system having a function to suppress radio wave radiation, comprising: cards, each for mounting electronic devices; a backboard, having a first end and a second end, for supporting said plurality of cards which stand closely together in parallel; first and second clock signal sources respectively generating first and second clock signals; first and second selecting gates, operatively connected to said first and second clock signal sources respectively, having outputs and alternatively selecting one of said first and second clock signals to be output; and a first and a second group of click signal lines, operatively connected to the outputs of said first and second selecting gates respectively, the clock signal lines in said first and second groups respectively being wired closely in parallel on said backboard and wired on said cards, for respectively conducting said first and second clock signals to said cards.
Claim 2
Dependent Claim 145 words
A duplex system having a function to suppress radio wave radiation, comprising: cards, each for mounting electronic devices; a backboard, having a first end and a second end, for supporting said plurality of cards which stand closely together in parallel; first and second clock signal sources respectively generating first and second clock signals; first and second selecting gates, operatively connected to said first and second clock signal sources respectively, having outputs and alternatively selecting one of said first and second clock signals to be output; and a first and a second group of click signal lines, operatively connected to the outputs of said first and second selecting gates respectively, the clock signal lines in said first and second groups respectively being wired closely in parallel on said backboard and wired on said cards, for respectively conducting said first and second clock signals to said cards.
Claim 3
Dependent Claim 34 words
A duplex system as claimed in claim 1, wherein said first and second clock signal sources are duplex clock signal sources mounted on two of said cards arranged at both ends of said backboard.
Claim 4
Dependent Claim 28 words
A duplex system as claimed in claim 1, wherein said pair of selecting gates are mounted on two of said cards arranged at both ends of said backboard.
Claim 5
Dependent Claim 53 words
A duplex system as claimed in claim 1, wherein said first and second clock signal lines have a potential level, said first and second selecting gates include a nonselecting gate, and the potential level of the clock signal lines connected to the output of the nonselecting gate is maintained at a fixed level.
Claim 6
Dependent Claim 16 words
A duplex system as claimed in claim 4, wherein said fixed level is a ground level.
Claim 7
Dependent Claim 42 words
A duplex system as claimed in claim 1, wherein the said first group of clock signal lines are respectively connected to said cards, and said second group of the clock signal lines in said second group are respectively connected to said cards.
Claim 8
Dependent Claim 56 words
A duplex system as claimed in claim 1, further comprising a first and a second group of buffer circuits, operatively connected between the outputs of said first and second selecting gates and said first and second group of clock signal lines, for amplifying the clock signal selected by one of said first and second selecting gates.
Claim 9
Dependent Claim 64 words
A duplex system as claimed in claim 1, further comprising a plurality of OR gates, respectively mounted on said cards, each having a first input end connected to an active clock signal line and a second input end connected to a standby clock signal line, said active clock signal line and said standby clock signal line being determined by said pair of selecting gates.
Claim 10
Dependent Claim 129 words
A duplex system having a function to suppress radio wave radiation, comprising: cards, each for mounting electronic devices; a backboard for supporting said cards which stand closely together in parallel; first and second clock signal sources for respectively generating first and second clock signals, said first and said second clock signal sources having outputs and being mounted on at least one of said cards located centrally on said backboard; and a first and a second group of clock signal lines, operatively connected to the outputs of said first and second clock signal sources respectively, the clocks signal lines in said first and second groups respectively being wired closely in parallel on said backboard and wired on said cards, for respectively conducting said first and second signals to said cards.
Claim 11
Dependent Claim 129 words
A duplex system having a function to suppress radio wave radiation, comprising: cards, each for mounting electronic devices; a backboard for supporting said cards which stand closely together in parallel; first and second clock signal sources for respectively generating first and second clock signals, said first and said second clock signal sources having outputs and being mounted on at least one of said cards located centrally on said backboard; and a first and a second group of clock signal lines, operatively connected to the outputs of said first and second clock signal sources respectively, the clocks signal lines in said first and second groups respectively being wired closely in parallel on said backboard and wired on said cards, for respectively conducting said first and second signals to said cards.
Claim 12
Dependent Claim 29 words
A duplex system as claimed in claim 9, wherein said first and said second clock signal sources are mounted on two of said cards arranged centrally on said backboard.
Claim 13
Dependent Claim 77 words
A duplex system as claimed in claim 9, further comprising a plurality of selecting gates respectively mounted on said cards, each of said selecting gates having a first input end for receiving said first clock signal through one of said first clock signal lines and having a second input end for receiving said second clock signal through one of said second clock signal lines, for selecting one of said first and second clock signals to be output.
Claim 14
Dependent Claim 64 words
A duplex system as claimed in claim 9, further comprising first and a second selecting gates, operatively and respectively connected between said first and second clock signal sources and said first and second group of clock signal lines, for alternatively selecting one of said first and second clock signals to be output to one of said first and second groups of clock signal lines.
Claim 15
Dependent Claim 31 words
A duplex system as claimed in claim 12, wherein a potential level of the clock signal lines connected to the output of the nonselecting gate are maintained at a fixed level.
Claim 16
Dependent Claim 16 words
A duplex system as claimed in claim 13, wherein said fixed level is a ground level.
Claim 17
Dependent Claim 65 words
A duplex system as claimed in claim 14, further comprising a plurality of OR gates, respectively mounted on said cards, each having a first input end connected to an active clock signal line and a second input end connected to a standby clock signal line, said active clock signal line and said standby clock signal line being determined by said first and second selecting gates.
Claim 18
Dependent Claim 71 words
A gate control system in a duplex system having cards on which electronic devices are mounted, clock signal sources generating clock signals, and clock signal lines conducting the clock signals to the cards, comprising: selecting gates, operatively connected to the clock signal lines, connected and adjacent to the clock signal sources and selecting one of the clock signal sources to conduct clock signals to the cards by the clock signal lines.
Claim 19
Dependent Claim 71 words
A gate control system in a duplex system having cards on which electronic devices are mounted, clock signal sources generating clock signals, and clock signal lines conducting the clock signals to the cards, comprising: selecting gates, operatively connected to the clock signal lines, connected and adjacent to the clock signal sources and selecting one of the clock signal sources to conduct clock signals to the cards by the clock signal lines.
Claim 20
Dependent Claim 29 words
A duplex system as claimed in claim 16, wherein the clock signal lines connected to a clock signal source that are not selected are maintained at a fixed level.
Claim 21
Dependent Claim 16 words
A duplex system as claimed in claim 17, wherein the fixed level is a ground level.
Claim 22
Dependent Claim 35 words
A duplex system as claimed in claim 16, wherein the cards are provided in parallel, and the clock signal sources are provided on one of a card and adjacent cards located centrally among the cards.
Claim 23
Dependent Claim 35 words
A duplex system as claimed in claim 17, wherein the cards are provided in parallel, and the clock signal sources are provided on one of a card and adjacent cards located centrally among the cards.
Claim 24
Independent Claim 69 words
A method of suppressing radio wave radiation in a duplex system, having clock signal sources generating clock signals and clock signal lines conducting the clock signals to the cards, comprising the step of: (a) selecting one of the clock signal sources to conduct clock signals to the cards by the clock signal lines; and (b) maintaining the clock signals generated by unselected clock signal sources at a fixed level.
Claim 25
Independent Claim 69 words
A method of suppressing radio wave radiation in a duplex system, having clock signal sources generating clock signals and clock signal lines conducting the clock signals to the cards, comprising the step of: (a) selecting one of the clock signal sources to conduct clock signals to the cards by the clock signal lines; and (b) maintaining the clock signals generated by unselected clock signal sources at a fixed level.

References Cited (Backward Citations)

US4185245A Cited
US4239982A Cited
US4661721A Cited
US4868414A Cited
US4954929A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-10-14 1995-04-15 1995-10-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-10-14 1999-04-15 1999-10-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-10-14 2003-04-15 2003-10-15 $7700.00 Window Closed / Lapsed

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