Size 1812 (EIA) or 4532 (IEC) Rated inductance 1,0 to 1000 mH Rated current 55 to 600 mA # Technical Documentation: B82432A1182K Common Mode Choke
Manufacturer : EPCOS (TDK Group)
Component Type : Surface Mount Common Mode Choke
Series : B82432A Series
## 1. Application Scenarios
### Typical Use Cases
The B82432A1182K is specifically designed for electromagnetic interference (EMI) suppression in high-frequency electronic circuits. Its primary function is to attenuate common mode noise while allowing differential signals to pass unimpeded.
Primary Applications:
- Differential signal line filtering in high-speed data interfaces
- USB 2.0/3.0 port protection for noise suppression
- Ethernet PHY filtering in network equipment
- HDMI/DVI interface EMI reduction in multimedia systems
- Switched-mode power supply input/output filtering
- Motor drive systems for brushless DC motor noise suppression
### Industry Applications
Consumer Electronics:
- Smartphones and tablets (charging ports, data interfaces)
- Television and display systems (HDMI/display port filtering)
- Gaming consoles (peripheral interface protection)
Automotive Electronics:
- Infotainment systems (CAN bus, Ethernet filtering)
- ADAS sensor interfaces
- Automotive networking applications
Industrial Equipment:
- PLC systems (communication interface protection)
- Industrial networking equipment
- Motor control systems
Telecommunications:
- Network switches and routers
- Base station equipment
- Data center hardware
### Practical Advantages and Limitations
Advantages:
- High impedance at target frequencies (optimized for 100-500 MHz range)
- Compact SMD package (1210 case size) saves board space
- Excellent common mode rejection with minimal differential signal attenuation
- High current handling capability (up to 1.2A rated current)
- Robust construction suitable for automated assembly processes
- Wide operating temperature range (-55°C to +125°C)
Limitations:
- Frequency-specific performance - optimized for specific EMI bands
- Limited to common mode noise - less effective for differential mode noise
- Saturation current constraints - may not suit high-power applications
- Package size limitations for very high current applications
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: Incurrent Current Rating Selection
- Problem : Selecting choke based solely on impedance without considering DC bias current
- Solution : Always verify DC bias curves and ensure operating current is below saturation threshold
Pitfall 2: Improper Placement
- Problem : Placing choke too far from noise source or sensitive components
- Solution : Position as close as possible to noise source or connector entry points
Pitfall 3: Inadequate Decoupling
- Problem : Relying solely on choke without proper bypass capacitors
- Solution : Implement complementary LC filtering with appropriate capacitors
### Compatibility Issues with Other Components
Positive Compatibility:
- Works well with ferrite beads for multi-stage filtering
- Compatible with TVS diodes for combined EMI and ESD protection
- Pairs effectively with common mode capacitors for enhanced filtering
Potential Conflicts:
- May interact with high-speed transceivers if impedance affects signal integrity
- Can conflict with certain oscillator circuits if placed too close
- Watch for resonance issues when combined with large capacitance values
### PCB Layout Recommendations
Optimal Placement:
```
[Noise Source] → [B82432A1182K] → [Sensitive Circuit]
(Close proximity) (Minimal trace length)
```
Critical Layout Guidelines:
1. Minimize lead lengths between choke and
