ELECTRICAL CHARACTERISTICS (continued)

PROTECTION AND DIAGNOSTICS (continued)

Symb ol

Parameter

Test Cond ition s

Mi n.

Typ .

Max.

Un it

•) Status Clamp Voltage

6

-0. 7

V

V

Switch-off T ime in

Short Circuit Condition

at Start -Up

Ω

ms

Over Current

Ω

140

A

Average Current in

Short Circuit

Ω

A

Open Load Current

Level

5

1250

mA

Thermal Shut-down

Temperat ure

140

Reset Temperature

125

exceed 10 mA at the input pin.

(

•) Status determination > 100 µs after the switching edge.

FUNCTIONAL DESCRIPTION

The device has a diagnostic output which

indicates

open

circuit (no

load)

and

over

temperature conditions. The output signals are

processed by internal logic.

To protect the device against short circuit and

over-current condition, the thermal protection

turns the integrated Power MOS off at a minimum

junction temperature of 140

temperature returns to about 125

automatically turned on again.

In short circuit conditions the protection reacts

with virtually no delay, the sensor being located in

the region of the die where the heat is generated.

PROTECTING

THE

DEVICE

AGAINST

REVERSE BATTERY

The simplest way to protect the device against a

continuous reverse battery voltage (-26V) is to

insert a Schottky diode between pin 1 (GND) and

ground, as shown in the typical application circuit

(fig. 3).

The consequences of the voltage drop across

this diode are as follows:

respect to power GND).

The undervoltage shutdown level is increased by

If there is no need for the control unit to handle

external analog signals referred to the power

GND, the best approach is to connect the

reference potential of the control unit to node [1]

(see application circuit infig. 4), which becomes

the common signal GND for the whole control

board.

place and no negative voltage appears on the

INPUT pin; this solution allows the use of a

standard diode, with a breakdown voltage able to

handle any ISO normalized negative pulses that

occours in the automotive environment.

VN30NSP

4/8