AN3256 Datasheet, PDF (17/23 Pages) STMicroelectronics – Low-cost LED driver for an A19 lamp

AN3256
8
Conducted EMI
Conducted EMI
Traces shown below are the maximum of 3 successive sweeps (max hold), peak values.
● Red = line 1
● Blue = line 2
Figure 23. Conducted EMI, dbµV versus frequency
Some work remains to be done. The input EMI choke L1 is too small. Damping resistors
across the choke should help at its parallel self-resonance.
Doc ID 17790 Rev 1
17/23