VND670SP_08 datasheet(13/20 Pages) STMICROELECTRONICS

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VND670SP

Application information

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3.2

Fault conditions

In case of a fault conditions the DIAGX/ENX pin is considered as an output pin by the device.

The fault conditions are:

●

overtemperature on one or both high-sides;

●

short to battery condition on the output (saturation detection on the external connected

Power MOSFET).

Possible origins of fault conditions may be:

●

OUTA is shorted to ground ---> overtemperature detection on high-side A.

●

OUTA is shorted to VCC ---> external Power MOSFET saturation detection (driven by

GATEA).

When a fault condition is detected, the user can know which power element is in fault by

monitoring the INA, INB, DIAGA/ENA and DIAGB/ENB pins.

In any case, when a fault is detected, the faulty half bridge is latched off. To turn-on the

respective output (GATEX or OUTX) again, the input signal must rise from low to high level.

3.3

Test mode

The PWM pin allows to test the load connection between two half-bridges. In the test mode

(Vpwm=-2V) the external Power Mos gate drivers are disabled. The INA or INB inputs allow to

turn-on the high-side A or B, respectively, in order to connect one side of the load at VCC

voltage. The check of the voltage on the other side of the load allow to verify the continuity of

the load connection. In case of load disconnection the DIADX/ENX pin corresponding to the

faulty output is pulled down.

Table 12.

Truth table in fault conditions (detected on OUTA)

INA

INB

DIAGA/ENA DIAGB/ENB

OUTA

OUTB

GATEA

GATEB

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