H01F 27/42
Circuits specially adapted for the purpose of modifying, or compensating for, electric
Official title: Circuits specially adapted for the purpose of modifying, or compensating for, electric characteristics of transformers, reactors, or choke coils (circuits for controlling transformers, reactors or choke coils, for the purpose of obtaining a desired output H02P13/00; impedance networks H03H)
H01F27/42 (Circuits specially adapted for the purpose of modifying, or compensating for, electric) appears on 344 US grants and 348 published applications in this corpus.
Search patents in H01F- Granted patents
- 344
- Published applications
- 348
- Assignees
- 246
- Inventors
- 747
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 2 | 0 |
| 1978 | 1 | 0 |
| 1979 | 1 | 0 |
| 1980 | 4 | 0 |
| 1981 | 1 | 0 |
| 1982 | 2 | 0 |
| 1983 | 1 | 0 |
| 1984 | 2 | 0 |
| 1985 | 2 | 0 |
| 1986 | 4 | 0 |
| 1987 | 3 | 0 |
| 1988 | 5 | 0 |
| 1989 | 1 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 0 | 0 |
| 1993 | 1 | 0 |
| 1994 | 3 | 0 |
| 1995 | 1 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 5 | 0 |
| 1999 | 2 | 0 |
| 2000 | 2 | 0 |
| 2001 | 3 | 3 |
| 2002 | 2 | 6 |
| 2003 | 5 | 4 |
| 2004 | 1 | 4 |
| 2005 | 5 | 6 |
| 2006 | 5 | 3 |
| 2007 | 4 | 10 |
| 2008 | 7 | 8 |
| 2009 | 6 | 4 |
| 2010 | 7 | 14 |
| 2011 | 4 | 8 |
| 2012 | 7 | 7 |
| 2013 | 0 | 10 |
| 2014 | 9 | 16 |
| 2015 | 12 | 17 |
| 2016 | 19 | 16 |
| 2017 | 14 | 36 |
| 2018 | 25 | 43 |
| 2019 | 39 | 21 |
| 2020 | 25 | 17 |
| 2021 | 29 | 20 |
| 2022 | 14 | 23 |
| 2023 | 14 | 10 |
| 2024 | 19 | 16 |
| 2025 | 14 | 11 |
| 2026 | 9 | 15 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Isolation transformer6 Oct 2026US 12,755,897 B2Inventec Corporation
- Radiation hardened active power transformer29 Sep 2026US 12,749,617 B2Rockwell Collins, Inc.
- Substrate embedded magnetic core inductors and method of making8 Sep 2026US 12,731,717 B2Intel Corporation
- Current transformer assemblies8 Sep 2026US 12,731,727 B2Schneider Electric USA, Inc.
- Method of efficiently transforming energy using a multifilar inductor with at least three switchable windings14 Jul 2026US 12,683,073 B2Richard H. Sherratt and Susan B. Sherratt Revocable Trust Fund
- Shorting block component for a current transformer8 Oct 2026US 2026/0312310 A1Schweitzer Engineering Laboratories, Inc.
- Direct Current Quantum Magnetic Transformer and Related Energy Saving Devices and Methods1 Oct 2026US 2026/0302048 A1Harmonify AB
- Integrated common-mode inductor and switching power converter having the same27 Aug 2026US 2026/0253778 A1Asian Power Devices Inc.
- High-energy scalable, pulse-power, multimode multifilar-wound inductor6 Aug 2026US 2026/0229402 A1Richard H. Sherratt and Susan B. Sherratt Trust Fund
- Power Transfer Control Method in a Rotary Transformer23 Jul 2026US 2026/0213067 A1Irp Nexus Group Ltd.
Most cited
By later US patents
- Planar transformer power supply266US 7,502,234 B2Aaron Medical Industries, Inc. · 2009
- System and method for providing a low power receiver design114US 6,377,315 B1Broadcom Corporation · 2002
- System and method for on-chip filter tuning78US 6,285,865 B1Broadcom Corporation · 2001
- Temperature compensation in a wireless transfer system77US 8,692,412 B2WiTricity Corporation · 2014
- Integrated switchless programmable attenuator and low noise amplifier57US 6,879,816 B2Broadcom Corporation · 2005