True Color PWM Delivers Constant Color with 400:1 Dimming Range # Technical Documentation: CDRH4D284R7 Power Inductor
Manufacturer : SUMIDA
Component Type : Shielded Drum Core Power Inductor
## 1. Application Scenarios
### Typical Use Cases
The CDRH4D284R7 is primarily employed in DC-DC converter circuits where stable current filtering and energy storage are critical. Common implementations include:
- Buck converter output stages (2-5A load applications)
- Boost converter input filtering
- Voltage regulator modules (VRMs) for processor power delivery
- LED driver circuits requiring constant current regulation
- Power management ICs in portable electronics
### Industry Applications
Consumer Electronics :
- Smartphones and tablets (power management subsystems)
- Laptop computer DC-DC conversion circuits
- Gaming consoles and portable devices
Automotive Electronics :
- Infotainment system power supplies
- Advanced driver assistance systems (ADAS)
- LED lighting control modules
Industrial Systems :
- PLC power modules
- Motor drive control circuits
- Industrial sensor power conditioning
Telecommunications :
- Network switch power circuits
- Base station power distribution
- Router and modem power supplies
### Practical Advantages and Limitations
Advantages :
- High saturation current (2.8A) enables robust performance in power-intensive applications
- Shielded construction minimizes electromagnetic interference (EMI) with adjacent components
- Low DC resistance (28mΩ typical) reduces power losses and improves efficiency
- Compact footprint (4.8mm × 4.8mm) suits space-constrained PCB designs
- Excellent thermal stability maintains performance across -40°C to +125°C operating range
Limitations :
- Limited to moderate frequency applications (typically < 5MHz)
- Not suitable for RF circuits due to core material characteristics
- Mechanical fragility requires careful handling during assembly
- Cost premium compared to unshielded alternatives in high-volume applications
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: Inadequate Current Headroom
- Problem : Operating near saturation current causes inductance drop and thermal issues
- Solution : Design with 20-30% current margin above expected peak operating current
Pitfall 2: Improper Thermal Management
- Problem : Overheating from poor airflow or excessive ripple current
- Solution : Implement thermal vias in PCB, ensure adequate clearance for air circulation
Pitfall 3: Resonance Issues
- Problem : Self-resonant frequency limitations affecting high-frequency performance
- Solution : Characterize circuit operation relative to inductor's self-resonant frequency (typically >50MHz)
### Compatibility Issues with Other Components
Semiconductor Compatibility :
- Switching MOSFETs : Ensure fast switching transitions to minimize core losses
- Controller ICs : Verify compatibility with inductor's DCR and saturation characteristics
- Capacitors : Match with appropriate output capacitors to maintain stability
Passive Component Interactions :
- Input capacitors : Position close to inductor to minimize high-frequency loop area
- Feedback networks : Account for inductor DCR in current sensing applications
- Decoupling capacitors : Place strategically to suppress switching noise
### PCB Layout Recommendations
Placement Guidelines :
- Position inductor within 5mm of switching IC for optimal performance
- Maintain minimum 2mm clearance from heat-sensitive components
- Orient inductor to minimize magnetic coupling with sensitive circuits
Routing Considerations :
- Use wide, short traces for high-current paths to reduce parasitic resistance
- Implement ground plane beneath inductor to provide shielding and thermal dissipation
- Route feedback and control signals away from inductor magnetic fields
