Compact and lightweight, High breakdown voltage, Surface mounting type# EE25NUH Technical Documentation
## 1. Application Scenarios
### Typical Use Cases
The EE25NUH ferrite core is primarily employed in switch-mode power supplies (SMPS) operating at frequencies between 100 kHz and 500 kHz. Common implementations include:
- Forward converters for medium-power applications (50W-200W)
- Flyback converters in isolated power supplies
- Push-pull converters for balanced power distribution systems
- DC-DC converters in industrial and automotive applications
### Industry Applications
Power Electronics Sector:
- Server power supplies and UPS systems
- Industrial motor drives and control systems
- Renewable energy inverters (solar/wind)
- Electric vehicle charging stations
Consumer Electronics:
- LCD/LED television power supplies
- Computer monitor power adapters
- Gaming console power units
- High-end audio amplifier power stages
Telecommunications:
- Base station power systems
- Network equipment power supplies
- Fiber optic transceiver power modules
### Practical Advantages
- High Saturation Flux Density : 510 mT at 100°C enables compact designs
- Low Core Loss : < 600 kW/m³ at 100 kHz, 200 mT, 100°C
- Excellent Temperature Stability : Operating range -40°C to +140°C
- Good DC Bias Performance : Maintains inductance under high DC current conditions
### Limitations
- Frequency Constraints : Optimal performance up to 500 kHz, efficiency degrades above 1 MHz
- Size Limitations : Maximum power handling ~250W in typical configurations
- Cost Considerations : Higher material cost compared to standard Mn-Zn ferrites
- Mechanical Fragility : Requires careful handling during assembly
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Core Saturation Issues:
- Problem : Insufficient core volume leading to premature saturation
- Solution : Calculate required AL value using Bmax = (V × t)/(N × Ae) and verify against DC bias curves
Thermal Management:
- Problem : Excessive temperature rise due to poor heat dissipation
- Solution : Implement thermal vias in PCB, ensure adequate airflow, consider forced cooling for high-density designs
Winding Losses:
- Problem : High AC resistance from skin and proximity effects
- Solution : Use Litz wire for high-frequency operation, optimize winding strategy (interleaving)
### Compatibility Issues
Semiconductor Compatibility:
- MOSFETs : Compatible with most modern power MOSFETs (600V-800V rating)
- Diodes : Requires fast recovery diodes (trr < 100 ns) for optimal performance
- Controllers : Works well with current-mode PWM controllers (UC384x, LT1241 series)
Capacitor Selection:
- Input Capacitors : Low ESR electrolytic or film capacitors recommended
- Output Capacitors : Ceramic capacitors for high-frequency bypassing
Magnetic Component Integration:
- Potential interference with nearby inductors - maintain minimum 2x core diameter separation
- Shielding requirements for sensitive analog circuits
### PCB Layout Recommendations
Power Stage Layout:
- Keep primary and secondary circuits physically separated
- Minimize loop areas in high-current paths
- Place snubber components close to switching devices
Thermal Management:
- Use thermal relief patterns for pin connections
- Implement copper pours for heat spreading
- Consider exposed pad designs for enhanced cooling
EMI Considerations:
- Provide adequate clearance (≥8mm) between primary and secondary sides
- Use guard traces for sensitive feedback circuits
- Implement proper grounding strategies (star grounding recommended)
## 3. Technical Specifications
### Key Parameter Explanations
Core Dimensions:
- Effective Cross-Sectional Area (Ae
