Circuit description

L6370Q

10/16

Doc ID 022313 Rev 1

3.1

Diagnostic truth table

3.2

Input section

The input section is an high impedance differential stage with high common and differential

mode range. There’s built-in offset of +1.4 V (typical value) and an hysteresis of 400 mV

(maximum value), to ensure high noise immunity.

3.3

Diagnostic logic

The operating conditions of the device are permanently monitored and the following

occurrences are signalled via the DIAG1/DIAG2 open-drain output pins:

●

the maximum current that can be sourced from the OUTPUT pin (for more details see

short circuit operation section).

●

Short circuit versus Vs.

●

Under voltage (UV)

●

Over temperature (OVT)

●

Open load, if the output current is less than 3 mA (typical value).

●

Output DMOS open according to the diagnostic truth Table 7.

Table 7.

Diagnostic truth table

Diagnostic conditions

Input

Output

Diag1

Diag2

Normal operation

L

H

L

H

H

H

H

H

L

H

L

H

H

L

H

H

L

H

H

H

L

L

H

H

(1)

(pin ON-DELAY grounded)

1.

A cold lamp filament, or a capacitive load may activate the current limiting circuit of the IPS, when the IPS

is initially turned on.

H

L

X

L

H

H

H

H

Output DMOS open

L

H

L

L

H

L

H

H

Overtemperature

L

H

L

L

H

H

L

L

L

H

L

L

L

L

L

L