Output stage

TDA7374

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3.4.4

Open ground

When the radio is in the ON condition and the ground is accidentally opened, a standard

audio amplifier will be damaged. On the TDA7374 protection diodes are included to avoid

any damage.

3.4.5

Inductive load

A protection diode is provided to allow use of the TDA7374 with inductive loads.

3.4.6

DC voltage

The maximum operating DC voltage for the TDA7374 is 18 V. However the device can

withstand a DC voltage up to 28 V with no damage. This could occur during winter if two

batteries are series connected to crank the engine.

3.4.7

Thermal shut-down

The presence of a thermal limiting circuit offers the following advantages:

1.

an overload on the output (even if it is permanent), or an excessive ambient

temperature can be easily withstood.

2.

the heatsink can have a smaller factor of safety compared with that of a conventional

circuit. There is no device damage in case of excessive junction temperature: all

The maximum allowable power dissipation depends upon the size of the external heatsink

(i.e. its thermal resistance); Figure 21 shows the dissipable power as a function of ambient

temperature for different thermal resistance.

Figure 21.

Maximum allowable power dissipation vs. ambient temperature

3.4.8

Loudspeaker protection

The TDA7374 guarantees safe operations even for the loudspeaker in case of accidental

shortcircuit.

switched OFF so limiting dangerous DC current flowing through the loudspeaker.