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PCE
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DIFF Subgroup
H03B 5/22

active element in amplifier being vacuum tube (H03B5/26 takes precedence)

Introduced: September 1968

Title

Titles differ between systems:

IPC: active element in amplifier being vacuum tube

CPC: active element in amplifier being vacuum tube (H03B5/26 takes precedence)

Full Title

Full titles differ between systems:

IPC:

Generation of oscillations using amplifier with regenerative feedback from output to input > with frequency-determining element comprising resistance and either capacitance or inductance, e.g. phase-shift oscillator > active element in amplifier being vacuum tube

CPC:

Generation of oscillations using amplifier with regenerative feedback from output to input (H03B9/00, H03B15/00 take precedence) > with frequency-determining element comprising resistance and either capacitance or inductance, e.g. phase-shift oscillator > active element in amplifier being vacuum tube (H03B5/26 takes precedence)

Additional Content IPC

Frequency-determining elements being part of bridge circuit in closed loop around which signal is transmitted; frequency-determining elements being connected via a bridge circuit to such a closed loop

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