STR0903 Series common mode inductor Toroidal Core Common Mode Choke with case,SMD common mode inductor
The STR0903 series SMD toroidal common-mode inductor uses a split-winding and single-layer winding design. It offers extremely low inter-winding capacitance and provides the highest common-mode impedance across a wide frequency range (50Hz-500KHz), delivering excellent common-mode interference suppression performance. The product has approximately 0.8% leakage inductance, which also provides some differential-mode suppression capability. The SMD package supports vapour phase soldering and infrared reflow soldering, with soldering heat resistance of 260°C/10 seconds. It is widely used in compact electronic ballasts, switching power supplies, and various common-mode interference suppression applications.
Features
- Split winding – lowest inter-winding capacitance
- Single-layer winding – highest common-mode impedance
- Frequency range – 50Hz to 500KHz
- Leakage inductance – approximately 0.8% (differential-mode suppression)
- Meets UL/CSA/IEC safety standards
- Material flammability rating – UL94-V0
- Operating voltage – 250VAC
- Operating temperature – -40°C to +105°C
APPLICATIONS
- Suppression of common-mode interferences
- Compact electronic ballasts in lamps
- Compact switch-mode power supplies
TECHNICAL INFORMATION
- Operating voltage: 250Vac
- IDC Max:Determined when superimposed
- lnductance test: HP4284A 10KHz 0.1V
- RDC:QuadTech 1880 Milliohmmeter
- Operating temperature: -40℃ to +105℃
- Storage Temperature: -40℃ to +105℃
- Temperature rise 40℃ Max
- Solder methods: Vapor Phase, Infrared Reflow
- Resistance to soldering heat:260℃ for 10 seconds
- Solvent resistance: Conforms to MIL-STD-202E
Note: Product specifications can be customized.
FAQ
Q: What are the advantages of split-winding and single-layer winding?
A: Split-winding places the primary and secondary windings physically separated on the core. This effectively reduces parasitic capacitance between windings and reduces capacitive coupling paths for high-frequency noise. Single-layer winding eliminates inter-layer parasitic capacitance, providing higher common-mode impedance and more stable filtering performance across a wide frequency range. Combined, these features enable the STR0903 series to achieve optimal common-mode noise suppression in the 50Hz-500KHz frequency band.
Q: What is the function of the approximately 0.8% leakage inductance?
A: The approximately 0.8% leakage inductance also provides some differential-mode interference suppression capability. In common-mode chokes, leakage inductance acts as a small inductor in series with the differential-mode path, providing some attenuation of differential-mode noise. This design allows the STR0903 series to address both common-mode and some differential-mode filtering requirements.
Q: What safety standards does this product comply with?
A: The product's creepage distance meets UL, CSA, and IEC safety requirements. All materials are UL94-V0 flame retardant certified. The design complies with EN 60938-2 (VDE 0565-2) standards. These certifications ensure the product can be used in power supplies and lighting equipment with strict safety requirements.
