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PCE
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DIFF Subgroup
H03F 3/44

with tubes only

Introduced: September 1968

Full Title

Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements > Amplifiers with two or more amplifying elements having their DC paths in series with the load, the control electrode of each element being excited by at least part of the input signal, e.g. so-called totem-pole amplifiers > with tubes only

No child classifications to compare. This is a leaf node in both IPC and CPC.

Top Applicants

Top Applicants (IPC)

Class H03,2013–2023, worldwide · Source: EPO PATSTAT

  1. QUALCOMM US 5,625
  2. SAMSUNG ELECTRONICS COMPANY KR 5,496
  3. MURATA MANUFACTURING COMPANY JP 5,478
  4. HUAWEI TECHNOLOGIES COMPANY CN 3,383
  5. INTEL CORPORATION US 3,091
  6. TEXAS INSTRUMENTS US 3,070
  7. MURATA MANUFACTURING COMPANY 2,722
  8. SKYWORKS SOLUTIONS US 2,290
  9. SEIKO EPSON CORPORATION 2,177
  10. IBM (INTERNATIONAL BUSINESS MACHINES CORPORATION) US 2,158

Top Applicants (CPC)

Class H03,2013–2023, worldwide · Source: EPO PATSTAT

  1. SAMSUNG ELECTRONICS COMPANY KR 7,293
  2. QUALCOMM US 7,085
  3. MURATA MANUFACTURING COMPANY JP 5,982
  4. HUAWEI TECHNOLOGIES COMPANY CN 4,641
  5. INTEL CORPORATION US 3,863
  6. TEXAS INSTRUMENTS US 3,409
  7. MURATA MANUFACTURING COMPANY 2,874
  8. SK HYNIX KR 2,644
  9. SKYWORKS SOLUTIONS US 2,545
  10. IBM (INTERNATIONAL BUSINESS MACHINES CORPORATION) US 2,437