STA335ML
Figure 12. Filterless output configuration
OUT1A
Applications
Left
OUT1B
OUT2A
Right
OUT2B
The filterless application is more critical in terms of EMI. It is quite important to follow the
suggestions below:
● Tracks from amplifier to speaker should be as short as possible.
● Ferrite beads can be used (instead of coils) to improve EMI performance.
– Ferrite beads must have a low impedance in the audio band and high impedance
at high frequencies.
– Place ferrite beads as close as possible to the IC.
– Ferrite filters must reduce EMI above 1 MHz.
– FCC and CE authorities test radiated emission above 30 MHz.
Figure 13. Filterless output configuration with snubber network
OUT1A
22 R
Left
330 pF
OUT1B
OUT2A
22 R
330 pF
Right
OUT2B
The presence of snubber networks reduce the EMI. The snubber networks should be placed
as close as possible to the IC.
Doc ID 17638 Rev 4
15/20