Common-mode chokes for LED lighting

The new ED100/ED101 EMC filter series from Schaffner has been designed specifically for the requirements of LED driver circuits. The new filter’s common-mode inductance is matched by a substantial differential-mode inductance. With only one component required on the PCB both types of noise can be mitigated, saving cost and space while increasing reliability.

In the past decade, light emitting diodes (LED) have disrupted the lighting industry. No application has remained untouched. Even harsh and ambitious applications such as powerful streetlamps and car headlights are now common applications for LEDs.

LEDs are very energy-efficient and robust but need to be powered carefully by a well-controlled current. They are very sensitive to overcurrent and “driver circuits” keep the current supply in the ideal range to prevent harm to the LEDs.

LED Lighting drivers need to be high in efficiency, low in cost and compliant to EMC regulations. For EMI suppression, common-mode chokes are a good alternative to X-capacitors when dealing with noise to ground. They reduce the leakage current and, by avoiding x-capacitors, help stabilising the power factor.

The ED100 ED101 series differential mode noise mitigation is available in two performance options depending on requirements: High (ED100) and very high (ED101). The new filters are designed for a maximum continuous operating voltage of 300 VAC, 50 / 60 Hz and meet the requirements for RoHS and REACH regulations.

The practical advantages of the ED100 ED101 series at a glance:

• Reduced number of components on the PCB with common and differential mode inductance limitation in one part.

• Choice of differential-mode attenuation: high (ED100) / very high (ED101)

• Rated currents up to 2 A with standard pins

• High reliability with MTBF of 13 million hours

• Increases the power factor and reduces the leakage current when x-capacitors are replaced.

Typical applications are LED equipment, especially LED driver circuits and displays, fluorescent lamp ballasts or any other application that with high demand for differential-mode performance.