SMT Power Inductors - DO3316P Series # Technical Documentation: DO3316P333MLD Power Inductor
Manufacturer : COILCRAFT
Component Type : Shielded Power Inductor
Part Number : DO3316P333MLD
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## 1. Application Scenarios
### Typical Use Cases
The DO3316P333MLD is a 33µH shielded power inductor designed for demanding power management applications where space constraints and EMI suppression are critical considerations. Typical implementations include:
- DC-DC Converter Output Filtering : Primary application in buck, boost, and buck-boost converter topologies
- Power Line Noise Suppression : Effective filtering of switching noise in power delivery networks
- Load Transient Response Improvement : Energy storage during rapid load changes
- RF Circuit Power Supply Decoupling : Clean power delivery to sensitive RF components
### Industry Applications
- Automotive Electronics : Engine control units, infotainment systems, ADAS power supplies
- Industrial Automation : PLCs, motor drives, sensor interface circuits
- Telecommunications : Base station power systems, network equipment
- Consumer Electronics : Smartphones, tablets, IoT devices, wearables
- Medical Devices : Portable medical equipment, patient monitoring systems
### Practical Advantages
- High Current Handling : Rated for 190mA saturation current (Isat) and 300mA thermal current (Irms)
- Excellent EMI Performance : Magnetic shielding minimizes radiated emissions
- Compact Footprint : 3.3×3.1mm package suits space-constrained designs
- Thermal Stability : Maintains inductance within specified tolerance across temperature range
- High Reliability : Robust construction suitable for automotive and industrial environments
### Limitations
- Limited Current Capacity : Not suitable for high-power applications exceeding 300mA
- Frequency Constraints : Optimal performance in 100kHz-2MHz switching frequency range
- Saturation Concerns : May experience inductance drop near maximum current ratings
- Cost Considerations : Higher per-unit cost compared to unshielded alternatives
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## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: Current Overload
- Issue : Operating near Isat causes inductance collapse
- Solution : Maintain 20-30% derating from Isat rating, implement current monitoring
Pitfall 2: Thermal Management
- Issue : Excessive core losses at high frequencies
- Solution : Use thermal vias, ensure adequate airflow, monitor temperature rise
Pitfall 3: Resonance Effects
- Issue : Self-resonant frequency limitations affecting high-frequency performance
- Solution : Characterize SRF (typically >10MHz) and design accordingly
### Compatibility Issues
Positive Compatibility
- Modern switching ICs (TI, Analog Devices, Maxim)
- Ceramic and tantalum capacitors
- Low-ESR output capacitors
Potential Conflicts
- High-dV/dt circuits may induce core saturation
- Incompatible with current-mode control requiring very low DCR
- May interact with nearby magnetic components
### PCB Layout Recommendations
Placement Strategy
- Position close to switching regulator IC (≤5mm)
- Orient to minimize magnetic coupling with sensitive circuits
- Maintain minimum 2mm clearance from other magnetic components
Routing Guidelines
- Use wide, short traces for high-current paths
- Implement ground plane beneath inductor
- Avoid routing sensitive signals under inductor body
- Place decoupling capacitors adjacent to inductor terminals
Thermal Management
- Incorporate thermal relief patterns
- Use multiple vias for heat dissipation
- Consider copper pour for improved thermal performance
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## 3. Technical Specifications
### Key Parameter Explanations
| Parameter | Value | Significance |
|-----------|-------|--------------|
| Inductance | 33µH ±20% | Determines energy storage and filtering capability
