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Built with an optimized ER39 core structure, this transformer offers high power handling capability, low core loss, and reduced leakage inductance, making it ideal for high-density and high-reliability designs. It operates efficiently over a wide frequency range and maintains low temperature rise even under continuous load conditions.
With robust insulation design and flexible customization options, the ER3902 transformer is widely used in industrial, consumer, and communication power applications requiring stable and efficient power conversion.
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The ER3902 7+7 High-Frequency Transformer is designed for compact switching power supply systems requiring efficient energy conversion, stable isolation performance, and reliable high-frequency operation. Built on an ER-core structure, it provides optimized magnetic performance for modern SMPS and DC-DC converter applications.
The 7+7 pin configuration supports flexible winding design and stable electrical connection, making it suitable for a wide range of low-to-medium power electronic systems.
Compared with standard flyback transformers, the ER3902 model offers improved structural stability and better integration into compact PCB layouts while maintaining efficient power transfer.
Customized turns ratios, winding structures, insulation levels, and pin configurations are available according to application requirements.
ER-core high-frequency transformer design
7+7 pin configuration for flexible layout
Stable isolated power conversion
Suitable for SMPS and DC-DC systems
Optimized for compact PCB integration
Reliable high-frequency performance
Consistent winding structure
Customizable electrical parameters
| Item | Specifications |
| Product Series | ER-type transformer series |
| Core Size | Diverse core size options |
| Operating Frequency | Broad high-frequency range: 15kHz to over 1.2MHz |
| Divided bands: | |
| 15kHz-60kHz | |
| 60kHz-120kHz | |
| 120kHz-600kHz | |
| 600kHz-1.2MHz | |
| Over 12MHz | |
| Power Coverage | Less than 8W up to 600W-1200W |
| Specific intervals: | |
| 8W-15W | |
| 15W-25W | |
| 25W-60W | |
| 60W-120W | |
| 120W-250W | |
| 250W-600W | |
| Typical Parameters | Operating frequency: 20kHz-500kHz |
| Output power: 80W-200W | |
| Operating Temperature | -40℃ to +125℃ |
| Product Functions | Flyback transformer, drive transformer, control transformer, inverter transformer, SMPS transformer |
| Also can be used as high-current inductor or isolated signal transformer | |
| Typical Applications | DC-DC converters, drive transformers, notebook power supplies, inverter power supplies, UPS, communication power supplies |
| Bobbin Style | Traditional bobbin styles |
| Customization & Service | All design parameters can be strictly customized according to customer requirements or industry specifications |
| Fully support global ODM/OEM cooperation |
Technical Specifications
| Main Category | Subcategory | Details |
| MOQ | Prototyping & Small-batch | 10 piece minimum order |
| Sample Service | Free proofing & custom service, 5 free samples (shipping at buyer’s cost) | |
| Bulk Order | 5,000 pieces and above with bulk pricing | |
| Lead Time | All Standard Components | Shipped within 5–7 working days |
| Custom Inductance / Pin Design (Sample) | Sample order confirmed within 5–7 working days | |
| Custom Inductance / Pin Design (Mass Order) | Shipped within 15–30 working days | |
| Payment Terms | Main Payment Term | T/T in advance, L/C at sight |
| Procurement Standard | Complies with global enterprise procurement standard for passive components | |
| Quality Deposit | No quality security deposit required | |
| Accepted Terms | FOB Shanghai / Nanjing / Hong Kong, T/T Advance | |
| Quality Assurance | Manufacturing Defects | Free replacement for issues caused by manufacturing defects |
| Inspection Report | Batch inspection reports available as certification upon customer request | |
| Packaging Specifications | Updated Packaging (2026) | Blister tray packaging; Sealed Tape & Reel for SMD products |
| Optional Packaging | Vacuum sealed packaging for customers with strict moisture-proof requirements |
