DIFF Subgroup
H03G 3/22 in amplifiers having discharge tubes
Introduced: September 1968
Full Title
Full titles differ between systems:
IPC:
Gain control in amplifiers or frequency changers > Automatic control > in amplifiers having discharge tubes
CPC:
Gain control in amplifiers or frequency changers > Automatic control ( combined with volume compression or expansion H03G7/00) > in amplifiers having discharge tubes
Of 3 combined children, 2 exist in both systems.
1 codes are CPC-only extensions.
Child Classifications
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- H03G 3/24 Control dependent upon ambient noise level or sound level IPC+CPC Available in IPC and CPC
Top Applicants
Top Applicants (IPC)
Class H03,2013–2023, worldwide · Source: EPO PATSTAT
- QUALCOMM US 5,625
- SAMSUNG ELECTRONICS COMPANY KR 5,496
- MURATA MANUFACTURING COMPANY JP 5,478
- HUAWEI TECHNOLOGIES COMPANY CN 3,383
- INTEL CORPORATION US 3,091
- TEXAS INSTRUMENTS US 3,070
- MURATA MANUFACTURING COMPANY 2,722
- SKYWORKS SOLUTIONS US 2,290
- SEIKO EPSON CORPORATION 2,177
- IBM (INTERNATIONAL BUSINESS MACHINES CORPORATION) US 2,158
Top Applicants (CPC)
Class H03,2013–2023, worldwide · Source: EPO PATSTAT
- SAMSUNG ELECTRONICS COMPANY KR 7,293
- QUALCOMM US 7,085
- MURATA MANUFACTURING COMPANY JP 5,982
- HUAWEI TECHNOLOGIES COMPANY CN 4,641
- INTEL CORPORATION US 3,863
- TEXAS INSTRUMENTS US 3,409
- MURATA MANUFACTURING COMPANY 2,874
- SK HYNIX KR 2,644
- SKYWORKS SOLUTIONS US 2,545
- IBM (INTERNATIONAL BUSINESS MACHINES CORPORATION) US 2,437