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US5334891A Expired / Lapsed US ⏱️ 0.0 years remaining

Variable delay circuit for producing a delay which varies as a hyperbolic function of the current intensity

Assignee: Bull SAS
•
Filing: 1993-04-26
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Granted: 1994-08-02
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Expires: 2013-04-26
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Abstract

Abstract The variable delay device 10 includes an ECL gate 11 associated with an adjusting circuit 23 acting on the resistance of resistive load elements 14, 15 of transistors 12, 13 and the resistive load element 18 of the current source 16 at the gate 11 to cause the current produced by the source 16 to vary linearly while keeping the voltage at the collectors of the transistors 12, 13 constant. The range of variation of the resistances is selected in such a way that the delay between the input signals IN, IN* and OUT, OUT* varies substantially linearly. The invention is particularly applicable to systems for digital data transmission at a very high rate, of more than 1 gigabit per second.

Inventors

  • 👤 Roland Marbot

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 02:00
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/26; H03H11/265

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 128 words
An variable delay device (10), comprising at least one differential amplifier (11) having first and second transistors (12, 13), a current source (16) for supplying current to said first and second transistors, first and second variable resistive load elements (14, 15) serially connected with said first and second transistors, respectively, varying means (123, 18a-18d) connected to said current source for varying current intensity supplied from the current source to produce a variable delay and maintaining means (23, 14a-14d, 15a-15d) for maintaining the voltages across each of said first and second load elements at a substantially constant value regardless of the current intensity flowing through said first and second load elements, whereby said variable delay varies as a hyperbolic function of the current intensity produced by the current source.
Claim 2
Dependent Claim 128 words
An variable delay device (10), comprising at least one differential amplifier (11) having first and second transistors (12, 13), a current source (16) for supplying current to said first and second transistors, first and second variable resistive load elements (14, 15) serially connected with said first and second transistors, respectively, varying means (123, 18a-18d) connected to said current source for varying current intensity supplied from the current source to produce a variable delay and maintaining means (23, 14a-14d, 15a-15d) for maintaining the voltages across each of said first and second load elements at a substantially constant value regardless of the current intensity flowing through said first and second load elements, whereby said variable delay varies as a hyperbolic function of the current intensity produced by the current source.
Claim 3
Dependent Claim 27 words
The device of claim 1, wherein the current source includes a third variable resistive load element (18) varied by the varying means to vary the current intensity.
Claim 4
Dependent Claim 46 words
The device of claim 1, wherein the maintaining means includes control terminal means and each of the first and second resistive load elements (14, 15) comprises a plurality of MOS transistors having parallel drain-to-source paths and gate electrodes connected in common to the control terminal means.
Claim 5
Dependent Claim 46 words
The device of claim 2, wherein the maintaining means includes control terminal means and each of the first and second resistive load elements (14, 15) comprises a plurality of MOS transistors having parallel drain-to-source paths and gate electrodes connected in common to the control terminal means.
Claim 6
Dependent Claim 38 words
The device of claim 1, wherein the current source includes a transistor (17) having a control electrode connected to a fixed reference potential (Vref) and a main current path serially connected to the third variable resistive load element.
Claim 7
Dependent Claim 16 words
The device of claim 1, wherein the current intensity is varied with a substantially linear variation.
Claim 8
Dependent Claim 18 words
The device of claim 2, wherein the current source has a polarization current with a substantially linear variation.
Claim 9
Dependent Claim 18 words
The device of claim 3, wherein the current source has a polarization current with a substantially linear variation.
Claim 10
Dependent Claim 18 words
The device of claim 4, wherein the current source has a polarization current with a substantially linear variation.
Claim 11
Dependent Claim 20 words
The device of claim 1, wherein the current intensity is varied with at least a squared function (I 2 ).
Claim 12
Dependent Claim 20 words
The device of claim 2, wherein the current intensity is varied with at least a squared function (I 2 ).
Claim 13
Dependent Claim 20 words
The device of claim 3, wherein the current intensity is varied with at least a squared function (I 2 ).
Claim 14
Dependent Claim 20 words
The device of claim 4, wherein the current intensity is varied with at least a squared function (I 2 ).
Claim 15
Dependent Claim 21 words
The device of claim 1, wherein the differential amplifier has two inputs which receive complementary versions of an input signal (IN).
Claim 16
Dependent Claim 13 words
The device of claim 1, wherein the differential amplifier is an ECL gate.
Claim 17
Dependent Claim 21 words
The device of claim 1, further including a plurality of differential amplifiers (11a-11d) having respective outputs applied to a multiplexer (16).
Claim 18
Dependent Claim 63 words
The device of claim 1, wherein said differential amplifier produces a first variable delay (Θ) and further comprises means (27a, 27b) for producing at least one fixed delay (Θf--FIG. 4) and selecting means (23, Sa-Sc) for selecting one of said at least one fixed delay and adding it to said variable delay to generate at least a second variable delay (Θa, Θb, Θc).

References Cited (Backward Citations)

US4422052A Cited
US4709170A Cited
EP0239696A2 Cited
US4866314A Cited
EP0315385A2 Cited
US4797586A Cited
US4862020A Cited
US4893036A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-08-01 1998-01-31 1998-08-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-08-01 2002-01-31 2002-08-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-08-01 2006-01-31 2006-08-02 $7700.00 Window Closed / Lapsed

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