DocID15068 Rev 6

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TDA7492P

Applications information

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6.5

Output low-pass filter

To avoid EMI problems, it may be necessary to use a low-pass filter before the speaker. The

cutoff frequency should be larger than 22 kHz and much lower than the output switching

frequency. It is necessary to choose the L-C component values depending on the loud

speaker impedance. Some typical values, which give a cutoff frequency of 27 kHz, are

shown in Figure 25 and Figure 26 below.

Figure 25. Typical LC filter for a 8

 speaker

Figure 26. Typical LC filter for a 4

 speaker