Patent US5248972A successfully refreshed from Google Patents.
US5248972A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Delta-sigma analog-to-digital converter with overload dependent modulator order
Assignee: Nokia Oyj
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Filing: 1992-04-03
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Granted: 1993-09-28
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Expires: 2012-04-03
Abstract
Abstract The invention relates to a method and an arrangement for stabilizing a high-order sigma-delta modulator comprising at least two integrator stages and a quantizing means. The first, the first two or the first three integrator stages of the high-order modulator form a low-order modulator which is stable at all input signal values. The arrangement comprises a means for resetting the integrator stages following the low-order modulator when the stable operation range of the high-order modulator is exceeded. For an MF modulator the arrangement further comprises a coupling means for decoupling the output of the last integrator of the high-order modulator from the quantizing means and for coupling the output of said low-order modulator to the quantizing means simultaneously with the resetting.
Inventors
- 👤 Teppo Karema
- 👤 Hannu Tenhunen
- 👤 Tapani Ritoniemi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:41
CPC Classifications
H; H03; H03M; H03M3/00; H03M3/30; H03M3/322; H03M3/358; H03M3/36; H03M3/366; H03M3/39; H03M3/412; H03M3/422; H03M3/43; H03M3/436; H03M3/438; H03M3/44; H03M3/446; H03M3/448; H03M3/452
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
132 words
An arrangement for stabilizing an MF-type high-order sigma-delta modulator comprising at least two integrator stages and a quantizing means to which the output of the last integrator stage is connected, wherein the first, the first two or the first three integrator stages in the high-order modulator form a lower-order modulator which is stable at all input signal values, the arrangement comprising a means for resetting the integrator stages following the lower-order modulator and a coupling means for decoupling the output of one of said series-connected integrator stages from the quantizing means and for coupling the output of said lower-order modulator to the quantizing means when the output voltage of said last integrator stage exceeds a predetermined threshold value corresponding to the upper limit of the stable operation range of the high-order modulator.
Claim 2
Dependent Claim
132 words
An arrangement for stabilizing an MF-type high-order sigma-delta modulator comprising at least two integrator stages and a quantizing means to which the output of the last integrator stage is connected, wherein the first, the first two or the first three integrator stages in the high-order modulator form a lower-order modulator which is stable at all input signal values, the arrangement comprising a means for resetting the integrator stages following the lower-order modulator and a coupling means for decoupling the output of one of said series-connected integrator stages from the quantizing means and for coupling the output of said lower-order modulator to the quantizing means when the output voltage of said last integrator stage exceeds a predetermined threshold value corresponding to the upper limit of the stable operation range of the high-order modulator.
Claim 3
Dependent Claim
40 words
An arrangement according to claim 1, wherein the coupling means recouples the output of the last integrator stage to the quantizing means with a predetermined delay after the output of the last integrator again falls below said predetermined threshold value.
Claim 4
Dependent Claim
25 words
An arrangement according to claim 2, wherein said predetermined delay is at least one clock cycle per each delaying integrator stage following said lower-order modulator.
References Cited (Backward Citations)
US4509037A
Cited
US5012244A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-09-27 | 1997-03-29 | 1997-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-27 | 2001-03-29 | 2001-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-27 | 2005-03-29 | 2005-09-28 | $7700.00 | Window Closed / Lapsed |