DocID023424 Rev 9

19/31

VNH5200AS-E

Application information

30

Figure 10. Behavior in fault condition (how a fault can be cleared)

Note:

In case the fault condition is not removed, the procedure for unlatching and sending the

device in Stby mode is:

- Clear the fault in the device (toggle: INA if ENA = 0 or INB if ENB =0)

- Pull low all inputs and Diag/EN pins within tDEL.

If the Diag/En pins are already low the fault can be cleared simply by toggling the input. The

device enters in stby mode as soon as the fault is cleared.

3.1

Reverse battery protection

Three possible solutions can be considered:

•

A Schottky diode D connected to VCC pin

•

An N-channel MOSFET connected to the GND pin (see Figure 9: Typical application

circuit)

•

A P-channel MOSFET connected to the VCC pin

The device sustains no more than -15 A in reverse battery conditions because of the two

Body diodes of the Power MOSFETs. Additionally, in reverse battery condition the I/Os of

VNH5200AS-E is pulled down to the VCC line (approximately -1.5 V).

Series resistor must be inserted to limit the current sunk from the microcontroller I/Os. If

IRmax is the maximum target reverse current through microcontroller I/Os, series resistor is:

R

V

IOs

V

CC

–

I

Rmax

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