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Loosely Regulated Feedback Control for High Efficiency Isolated Dc-Dc Converters

US 9,143,047 In force, term unresolved
OverviewFamilyAssignmentsSources & methods

Term ends no later than Mar 24, 2031 · Medium confidence

In force on USPTO's status record and by its fee record. A terminal disclaimer on file may shorten this term, possibly to a date already past; its reference document is unresolved, so the date above is an upper bound and no earlier date is guessed.

Filed Nov 9, 2011 as application 13/293,022 · Granted Sep 22, 2015
Base term, 20 years from filing
Today
20 years from filing
2011 2031
Clock starts
Mar 24, 2011
Ends no later than
Mar 24, 2031
Granted
Sep 22, 2015
base term fee events Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
None
Term adjustment
No prosecution delay on this record.
Unresolved
Terminal disclaimer
On file, reference document not resolved, so the date above is an upper bound. We do not guess the cap.
2 of 3
Maintenance fees paid
Three maintenance fees fall due, at 3.5, 7.5 and 11.5 years from grant. This counts the ones the record shows paid.
4
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

This patent's term is its 20-year base term, with no adjustment for prosecution delay. A terminal disclaimer is on file with no resolved reference, so no cap is applied and none is guessed. 2 of 3 maintenance fees are paid so far. Confidence: Medium. from the record

How we calculated this date

One row per rule, each showing its own input and what it did to the date. A step we could not verify says so instead of resolving itself.
StepInputDate after this stepConfidence
Base term, 20 years from filingClock starts Mar 24, 2011, when application 13/070,959, the earliest non-provisional in its chain, was filed (this one was filed Nov 9, 2011)Mar 24, 2031High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capDisclaimer on file (approved), reference document not resolvedno cap applied, and none guessedMedium confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderno later than Mar 24, 2031Medium confidence

This family

US 8,934,267In force
Nov 2031
Nov 2031
US 9,143,047this patent
no later than Mar 2031
no later than Mar 2031
US 9,520,772In force
Nov 2031
Nov 2031
US 10,218,265In force
Apr 2031
Apr 2031
The applications whose file history this site holds. The family may have others.

Assignments

Assignment documents as recorded at the USPTO, oldest first, with the reel and frame each was recorded at. A recorded assignment is a filed document, not a statement of current ownership, and the absence of a later one is not evidence that the last one still stands.
RecordedAssignorAssigneeConveyance
Dec 8, 2011
Reel 27351, frame 939
Wildrick, CarlTDK-Lambda CorporationAssignment of Assignor's Interest

Sources

Google Patents · The patent document at USPTO · Assignment records at USPTO

USPTO account required: This application in Patent Center · USPTO's maintenance fee lookup

Maintenance fee events come from USPTO's own fee records. Its fee lookup asks for the patent number and the application number.

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