Inductor self resonant frequency SRF
We measured Series Resonant Frequency “SRF” of some axial, SMD and hand wind inductors.
The self resonant frequency of an inductor is the frequency at which the parasitic capacitance of the inductor resonates with the ideal inductance of the inductor resulting in an extremely high impedance. At this frequency the device looks like an open circuit.
The parasitics of an inductor vary based on the type of inductor – wire wound inductor, multi-layer inductor, conductive film inductor etc.
Testing.
Axial inductors like this one:
Axial inductor 560nH Series Resonant Frequency SRF
Axial inductor 1uH SRF
Axial inductor 10uH Series Resonant Frequency
Axial inductor 22uH SRF
Axial inductor 100uH Series Resonant Frequency SRF
Axial inductor 1000uH SRF
Axial inductor Iskra amp measured inductance 5.9uH
Axial inductor Iskra amp 5.9uH S21
BCN-560N SMD Chip inductor 560nH SRF from rf-microwave
BCN-10U SMD Chip inductor 10µH SRF from rf-microwave
Hand wind inductor (ver2) measured inductance 2.7µH
Hand wind inductor 2.7uH (ver2) S21
Hand wind inductor (ver3) measured inductance 11.3 µH
Hand wind inductor 11.3uH (ver3) S21
Hand wind inductor (ver24) measured inductance 45 µH
Hand wind inductor 45 uH (ver24) S21
Capacitor self resonant frequency SRF popular for amateur use. We used 0805 and 1206 SMD capacitors, film capacitors and electrolytic capacitors with wire + VIA length about 2 to 4mm. You can learn more about it in the link here.
All measurements were conduced on HP8753ES. This presentation is for amateur use only.
73 Goran YU1CF