Applications information

TDA7492P

22/26

Doc ID 15068 Rev 5

6.6

Protection functions

The TDA7492P is fully protected against overvoltages, undervoltages, overcurrents and

thermal overloads as explained here.

Overvoltage protection (OVP)

page 8 the overvoltage protection is activated which forces the outputs to the

high-impedance state. When the supply voltage drops to below the threshold value the

device restarts.

Undervoltage protection (UVP)

specifications on page 8 the undervoltage protection is activated which forces the outputs to

the high-impedance state. When the supply voltage recovers the device restarts.

Overcurrent protection (OCP)

page 8 the overcurrent protection is activated which forces the outputs to the

high-impedance state. Periodically, the device attempts to restart. If the overcurrent

by the R-C components connected to pin STBY.

Thermal protection (OTP)

and the positive and negative PWM outputs are forced to 50% duty cycle. If the junction

device shuts down and the output is forced to the high-impedance state. When the device

cools sufficiently the device restarts.

6.7

Diagnostic output

The output pin DIAG is an open-drain transistor. When the protection is activated it is in the

high-impedance state. The pin can be connected to a power supply (<26 V) by a pull-up

resistor whose value is limited by the maximum sinking current (200 µA) of the pin.

Figure 27.

Behavior of pin DIAG for various protection conditions

TDA7492P

Protection logic

R1

DIAG

VDD

VDD

Overcurrent

protection

Restart

Restart

OV, UV, OT

protection