H03H 11/1217
Using a plurality of operational amplifiers
Official title: {using a plurality of operational amplifiers (H03H11/1204 takes precedence; parallel-T filters H03H11/1295)}
H03H11/1217 (Using a plurality of operational amplifiers) appears on 277 US grants and 181 published applications in this corpus.
Search patents in H03H- Granted patents
- 277
- Published applications
- 181
- Assignees
- 171
- Inventors
- 451
- Latest grant
- 26 May 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 12 | 0 |
| 1977 | 11 | 0 |
| 1978 | 3 | 0 |
| 1979 | 5 | 0 |
| 1980 | 3 | 0 |
| 1981 | 10 | 0 |
| 1982 | 3 | 0 |
| 1983 | 3 | 0 |
| 1984 | 3 | 0 |
| 1985 | 4 | 0 |
| 1986 | 6 | 0 |
| 1987 | 4 | 0 |
| 1988 | 1 | 0 |
| 1989 | 4 | 0 |
| 1990 | 3 | 0 |
| 1991 | 3 | 0 |
| 1992 | 2 | 0 |
| 1993 | 5 | 0 |
| 1994 | 1 | 0 |
| 1995 | 2 | 0 |
| 1996 | 3 | 0 |
| 1997 | 1 | 0 |
| 1998 | 1 | 0 |
| 1999 | 6 | 0 |
| 2000 | 5 | 0 |
| 2001 | 4 | 2 |
| 2002 | 7 | 2 |
| 2003 | 1 | 1 |
| 2004 | 3 | 8 |
| 2005 | 5 | 11 |
| 2006 | 11 | 8 |
| 2007 | 3 | 10 |
| 2008 | 11 | 8 |
| 2009 | 5 | 7 |
| 2010 | 3 | 16 |
| 2011 | 7 | 4 |
| 2012 | 4 | 6 |
| 2013 | 13 | 13 |
| 2014 | 13 | 15 |
| 2015 | 15 | 8 |
| 2016 | 10 | 5 |
| 2017 | 13 | 14 |
| 2018 | 7 | 2 |
| 2019 | 2 | 6 |
| 2020 | 6 | 6 |
| 2021 | 7 | 9 |
| 2022 | 4 | 4 |
| 2023 | 7 | 4 |
| 2024 | 5 | 6 |
| 2025 | 5 | 4 |
| 2026 | 2 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- H03H 11/1252Two integrator-loop-filters100
- H03H 11/1239Modifications to reduce influence of variations of temperature10
- H03H 11/1243Simulation of ladder networks8
- H03H 11/1234Modifications to reduce detrimental influences of amplifier imperfections7
- H03H 11/1221Theory6
- H03H 11/1226Filters using operational amplifier poles5
- H03H 11/123Modifications to reduce sensitivity3
Recent patents
- Active RC-type filter and method of implementing an active RC-type filter26 May 2026US 12,640,710 B2NXP B. V.
- Adaptive radio frequency filter with improved linearity17 Feb 2026US 12,555,882 B2Thales
- Active filter device and electric compressor comprising same16 Dec 2025US 12,500,574 B2Sanden Corporation
- Canonical lowpass filter with digitally programmable cutoff frequency settings using current followers16 Dec 2025US 12,500,575 B2King Fahd University of Petroleum and Minerals
- Audio amplifying circuit and playing device21 Oct 2025US 12,451,849 B2Rda Microelectronics (Shanghai) Co., Ltd.
- Noise filter25 Jun 2026US 2026/0180428 A1Mitsubishi Electric Corporation
- Ripple Reduction Using Chopper Amplifiers26 Feb 2026US 2026/0058622 A1
- Canonical lowpass filter with digitally programmable cutoff frequency settings using current followers4 Sep 2025US 2025/0279767 A1King Fahd University of Petroleum and Minerals
- Filtering device and radar sensor including the same7 Aug 2025US 2025/0253828 A1Samsung Electronics Co., Ltd.
- Active filter device and electric compressor comprising same6 Mar 2025US 2025/0080086 A1Sanden Corporation
Most cited
By later US patents
- Tissue signature tracking tranceiver126US 4,584,880 ADymax Corporation · 1986
- Second order active filters107US 5,006,810 ANorthern Telecom Limited · 1991
- Direct conversion receivers and filters adapted for use therein98US 6,335,656 B12002
- Filter design tool75US 8,930,874 B2Analog Devices, Inc. · 2015
- Digital subscriber line (DSL) modem compatible with home networks72US 6,831,975 B1Texas Instruments Incorporated · 2004