This Product Selection Guide contains information to help select products in the Common Mode Chokes category on DigiKey.com
A common mode choke is an electrical filter that blocks high frequency noise common to two or more data or power lines while allowing the desired DC or low-frequency signal to pass. Common mode (CM) noise current is typically radiated from sources such as unwanted radio signals, unshielded electronics, inverters and motors. Left unfiltered, this noise presents interference problems in electronics and electrical circuits.
SelectionCharacteristics
Filter Type: Defines if the filter is for power and/or signal lines.
Number of Lines: Indicates the number of galvanically isolated current paths that pass through a device.
Impedance @ Frequency: Characterizes the total magnitude of opposition to AC current flow through a device, and the test frequency at which the characterization is made.
Inductance @ Frequency: Characterizes device inductance at the test frequency indicated, subject to manufacturer’s test conditions.
Current Rating (Max): Typically this represents the maximum current to which a device will meet its given specifications. Exceeding this current may damage the device and/or other system components.
DC Resistance (DCR) (MAX): Characterizes the maximum resistance of a current path through a device.
Voltage Rating - DC: Typically this represents the maximum DC voltage rating to which a device will meet its given specifications. Exceeding this voltage rating may damage the device and other system components.
Voltage Rating - AC: Typically this represents the maximum AC voltage rating to which a device will meet its given specifications. Exceeding this voltage rating may damage the device and other system components.
Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.
Ratings: Minimum performance standards of the device, which are typically set by a third party.
Approval Agency: An indication that the product meets the minimum safety standards of an approving agency. These agencies are either government entities or private third-party labs that protect consumer safety.
Features: These are different capabilities or properties of the device such as industrial.
Mounting Type: Indicates how the device is attached.
Size/Dimension: The physical dimensions of the device. Typically length X width.
Height (Max): Indicates how far the device will extend above the surface to which it has been attached.
Package/Case: Indicates the type of protective case used on an electronic component to allow easy handling, installation, and protection. This selection was determined to be the closest industry standard applicable to the supplier’s device packaging. Typically it is best to check the actual dimensions from the datasheet rather than depend on this terminology when designing your circuit.
ProductExamples
| MFR PART # | 744823601 |
|---|---|
| DIGIKEY PART # | 732-1444-ND |
| MANUFACTURER | Würth Elektronik |
| DESCRIPTION | CMC 1MH 6A 2LN TH |
| DATASHEET | Click Here |
| MFR PART # | 744839003460 |
|---|---|
| DIGIKEY PART # | 732-10867-ND |
| MANUFACTURER | Würth Elektronik |
| DESCRIPTION | CMC 3MH 46A 3LN TH |
| DATASHEET | Click Here |
| MFR PART # | 744253101 |
|---|---|
| DIGIKEY PART # | 732-14096-2-ND |
| MANUFACTURER | Würth Elektronik |
| DESCRIPTION | CMC 100UH 450MA 3LN SMD |
| DATASHEET | Click Here |
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MediaLinks
TechForum
How Common Mode Chokes Work
TechForum Search: Common Mode Choke
Product Training Modules
Common Mode Choke
Video Library
Video Library: Common Mode Choke