Panasonic – New metal core technology in power choke coils enables package size reductions

Panasonic has developed a metal composite powder core for its ETQP series of power choke coils to meet market demand for coils offering higher performance in smaller package sizes.

Panasonic has met this demand in the ETQP series by better controlling the particle size of the metal powder in the core of its power choke coils. This improved production technology results in high magnetic flux and high permeability, and therefore better DC or AC bias characteristics. The new technology also prevents the coils from suffering from thermal ageing.

The monolithic structure of the ETQP devices, which have a reduced pathway for magnetic flow, produces better electrical characteristics than ferrite coils. As a result, the ETQP series coils are able to provide equivalent electrical and magnetic performance in a device with a case size some 30-50% smaller than that of a ferrite coil.

The ETQP devices are available in versions with inductance values ranging from 1μH to 100μH.

The structure of the ETQP coils damps the terminals and leads the inductance wire outside, bonded tightly to the body of the coil. This robust design makes the ETQP series able to withstand continuous vibrations of up to 30G, and provides for high solder-joint reliability and thermal performance.


  • Inductance stable over wide temperature range
  • Low buzz noise
  • Low resistance and eddy current
  • Operating-temperature range:
    -55°C to 155°C
  • No saturation
  • AEC-Q200 qualified


  • Noise filters
  • DC-DC converters