Application information

TDA7498MV

20/26

DocID016505 Rev 6

5.6

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 and C component values depending

on the loudspeaker impedance. Some typical values, which give a cutoff frequency of 27

kHz, are shown in Figure 23: "Typica

l LC filter for an 8 Ω speaker" and Figure 24: "Typical

LC filter for a 6 Ω speaker" below.

Figure 23

: Typical LC filter for an 8 Ω speaker

Figure 24: Typical LC filter

for a 6 Ω speaker

5.7

Protection functions

The TDA7498MV is fully protected against overvoltages, undervoltages, overcurrents and

thermal overloads as explained here.

Overvoltage protection (OVP)

If the supply voltage exceeds the value for VOVP given in Table 6: "Electrical specifications

", the overvoltage protection is activated which forces the outputs to the high impedance

state. When the supply voltage falls back to within the operating range, the device restarts.