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DIFF Subclass Not Allocatable
H03J

TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS

Introduced: September 1968

Description

H03J covers devices and methods for adjusting the resonant frequency of LC circuits and selecting among multiple resonant circuits. This includes mechanical tuning mechanisms (variable capacitors, inductors), electronic tuning approaches (varactor diodes, voltage-controlled oscillators), and circuit selection switching. The class encompasses applications in radio receivers, transmitters, and frequency-selective filters where precise frequency control or channel selection is required. Related but separate classes handle specific oscillator designs (H03B) and general frequency control or synchronization circuits (H03L).

Of 6 combined children, 5 exist in both systems.

1 codes are CPC-only extensions.

Note: 1 CPC extensions are marked as secondary classification only.

3 shared codes have differing titles between IPC and CPC.

Child Classifications

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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