Common Mode Choke Coil Film Type DLP11S/DLP11T Series (0504 Size) # Technical Documentation: DLP11SA350HL2L
*Manufacturer: MURATA*
## 1. Application Scenarios
### Typical Use Cases
The DLP11SA350HL2L is a high-performance, surface-mount common mode choke designed for electromagnetic interference (EMI) suppression in high-frequency digital circuits. Primary applications include:
- USB 3.0/3.1/3.2 interfaces for signal integrity preservation
- HDMI/DVI display ports to mitigate common mode noise
- Ethernet PHY circuits in networking equipment
- High-speed serial interfaces (SATA, PCI Express)
- Differential signal lines in communication systems
### Industry Applications
- Consumer Electronics : Smart TVs, gaming consoles, set-top boxes
- Computing Systems : Motherboards, servers, storage devices
- Telecommunications : Network switches, routers, base stations
- Automotive Infotainment : In-vehicle entertainment and connectivity systems
- Industrial Automation : PLCs, industrial PCs, control systems
### Practical Advantages
- Excellent common mode noise suppression (up to 30 dB at 1 GHz)
- High differential signal integrity with minimal insertion loss
- Compact 1005 size (1.0 × 0.5 mm) for space-constrained designs
- High current rating (350 mA) for power line applications
- Wide operating temperature range (-40°C to +85°C)
### Limitations
- Frequency-dependent performance with reduced effectiveness below 100 MHz
- Limited to common mode noise suppression (ineffective for differential noise)
- Current saturation may occur beyond rated specifications
- Not suitable for high-voltage applications (>25 V)
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: Incorrect Placement
- *Issue*: Placing choke too far from noise source
- *Solution*: Position immediately after connector or noise-generating IC
Pitfall 2: Inadequate Grounding
- *Issue*: Poor ground connection reduces effectiveness
- *Solution*: Use solid ground plane and multiple vias
Pitfall 3: Signal Integrity Degradation
- *Issue*: Excessive trace length before/after choke
- *Solution*: Keep differential pair lengths matched and minimal
### Compatibility Issues
- Impedance Matching : Ensure characteristic impedance matches system requirements (typically 90Ω for USB)
- DC Bias Dependence : Performance degrades with increasing DC current
- Frequency Response : Verify compatibility with system operating frequency
- Temperature Sensitivity : Consider derating in high-temperature environments
### PCB Layout Recommendations
```
Critical Layout Guidelines:
1. Place choke within 5 mm of noise source/connector
2. Maintain differential pair symmetry
3. Use ground plane beneath choke (no splits)
4. Keep adjacent traces at least 3× width away
5. Avoid vias between choke and connector
```
Trace Routing:
- Maintain consistent 100Ω differential impedance
- Keep trace lengths equal (±0.1 mm tolerance)
- Use 45° angles instead of 90° bends
- Minimize layer transitions
Grounding:
- Solid ground reference plane essential
- Multiple ground vias near mounting pads
- Isolate from noisy digital grounds
## 3. Technical Specifications
### Key Parameters
| Parameter | Value | Unit | Conditions |
|-----------|-------|------|------------|
| Impedance | 35 | Ω | 100 MHz |
| Rated Current | 350 | mA | DC |
| DC Resistance | 0.45 | Ω | Max |
| Operating Temp | -40 to +85
