| Image | Part Number | Description / PDF | Quantity | Rfq |
|---|---|---|---|---|
 |
J.W. Miller / Bourns |
CMC 20MH 2.9A 2LN TH |
230 |
|
 |
J.W. Miller / Bourns |
CMC 2MH 3.5A 2LN SMD |
3970 |
|
 |
J.W. Miller / Bourns |
CMC 40UH 900MA 2LN SMD AEC-Q200 |
2634 |
|
 |
J.W. Miller / Bourns |
CMC 60UH 2A 2LN 600 OHM CHAS MT |
0 |
|
 |
J.W. Miller / Bourns |
CMC 51UH 500MA 2LN SMD |
4027 |
|
 |
J.W. Miller / Bourns |
CMC 7MH 2.8A 2LN TH |
0 |
|
 |
J.W. Miller / Bourns |
CMC 230MA 2LN 1KOHM SMD AEC-Q200 |
182 |
|
 |
J.W. Miller / Bourns |
CMC 1MH 3.6A 2LN TH |
0 |
|
 |
J.W. Miller / Bourns |
CMC 200UH 7A 2LN SMD |
3459 |
|
 |
J.W. Miller / Bourns |
CMC 10UH 1.6A 2LN 200 OHM SMD |
30337 |
|
 |
J.W. Miller / Bourns |
CMC 4.25MH 1A 2LN TH |
281 |
|
 |
J.W. Miller / Bourns |
CMC 2.55MH 2A 2LN TH |
0 |
|
 |
J.W. Miller / Bourns |
CMC 4.7MH 400MA 2LN SMD AEC-Q200 |
5900 |
|
 |
J.W. Miller / Bourns |
CMC 20MH 600MA 2LN TH |
4960 |
|
 |
J.W. Miller / Bourns |
COMMON MODE CHOKE 12MH 4A 2LN TH |
240 |
|
 |
J.W. Miller / Bourns |
CMC 330UH 300MA 2LN 900 OHM SMD |
1431 |
|
 |
J.W. Miller / Bourns |
CMC 300MA 2LN 260 OHM SMD |
0 |
|
 |
J.W. Miller / Bourns |
CMC 470UH 1.1A 2LN 1 KOHM SMD |
1459 |
|
 |
J.W. Miller / Bourns |
CMC 4.25MH 4A 2LN TH |
216 |
|
 |
J.W. Miller / Bourns |
CMC 470UH 500MA 2LN SMD |
951 |
|
Common Mode Chokes (CMCs) are passive electronic components designed to suppress electromagnetic interference (EMI) by blocking high-frequency noise currents while allowing DC or low-frequency signals to pass. They play a critical role in ensuring electromagnetic compatibility (EMC) in modern electronic systems, particularly in power supplies, communication interfaces, and industrial equipment.
| Type | Functional Characteristics | Application Examples |
|---|---|---|
| High-Frequency CMCs | Optimized for >1 MHz noise suppression | Switching power supplies, USB interfaces |
| Low-Frequency CMCs | Effective in 10 kHz 1 MHz range | Motor drives, industrial sensors |
| Multi-Winding CMCs | Multiple coils for differential/balanced circuits | Telecom transformers, Ethernet interfaces |
| SMD CMCs | Surface-mount design for compact PCB integration | Smartphones, IoT devices |
| High-Current CMCs | Rated for >10A continuous operation | EV charging stations, solar inverters |
A typical CMC consists of: - Ferrite Core: Made of manganese-zinc (MnZn) or nickel-zinc (NiZn) materials for high permeability - Dual Windings: Symmetrically wound coils with equal turns to maintain signal integrity - Encapsulation: Flame-retardant epoxy resin for mechanical protection - Termination: Tin-plated copper leads or SMD pads
| Parameter | Description | Importance |
|---|---|---|
| Inductance (H) | 100 @ 100 MHz typical | Determines noise suppression effectiveness |
| Rated Current (A) | 0.1 50 A DC | Prevents core saturation under load |
| Impedance Range | 100 MHz 1 GHz | Defines operational frequency bandwidth |
| DC Resistance ( ) | 0.01 5 | Affects power efficiency |
| Operating Temp ( C) | -55 to +150 C | Ensures reliability in harsh environments |
Major industries include: - Consumer Electronics: Laptop chargers, smart TVs - Industrial Automation: PLC controllers, CNC machines - Medical Equipment: MRI scanners, patient monitors - Renewable Energy: Wind turbine inverters, battery storage systems - Telecommunications: 5G base stations, fiber optic transceivers
| Manufacturer | Product Series | Key Features |
|---|---|---|
| TDK Corporation | ACT1210 Series | 1200 @ 100 MHz, 1.5 A rating |
| Sumida | CDRH3D28 Series | High saturation resistance for EV chargers |
| Coilcraft | 114000C Series | AEC-Q200 qualified for automotive applications |
| W rth Elektronik | 744210 Series | Compact SMD design for 10GbE interfaces |
Key considerations: 1. Match impedance curve with target noise frequency 2. Derate current capacity by 20% for safety margins 3. Choose SMD variants for automated PCB assembly 4. Verify temperature ratings for industrial applications 5. Prioritize AEC-Q qualified parts for automotive use
Current trends include: - Miniaturization through advanced nanocrystalline cores - Integration with TVS diodes for combined EMI/surge protection - Development of 1000+ Amp CMCs for data center power systems - Adoption of RoHS-compliant materials - Implementation of embedded thermal sensors for smart monitoring
Application Case: A server power supply uses TDK ACT1210-600M CMC to suppress 150 MHz switching noise, achieving 40 dB reduction in conducted emissions.