TDA7374B
DC Voltage
Figure 17: Maximum Allowable Power
Dissipation vs. Ambient Temperature
The maximum operating DC voltage for the
TDA7374B is 18V.
However the device can withstand a DC voltage
up to 28V with no damage. This could occur dur-
ing winter if two batteries are series connected to
crank the engine.
Thermal Shut-down
The presence of a thermal limiting circuit offers
the following advantages:
1)an overload on the output (even if it is perma-
nent), 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 happens
Loudspeaker Protection
is that Po (and therefore P ) and Id are re-
tot
duced.
The TDA7374B guarantees safe operations even
for the loudspeaker in case of accidental shortcir-
cuit.
Whenever a single OUT to GND, OUT to VS short
circuit occurs both the outputs are switched OFF
so limiting dangerous DC current flowing through
the loudspeaker.
The maximum allowable power dissipation de-
pends upon the size of the external heatsink (i.e.
its thermal resistance); Fig. 17 shows the dissi-
pable power as a function of ambient temperature
for different thermal resistance.
9/13
STMICROELECTRONICS [ ST ]
