Datasheet

TLE 4278 G
Data Sheet 13 Rev. 1.4, 2007-02-19
Watchdog Activating
The calculation of the external resistor which adjusts the watchdog switch off threshold
can be done by Equation (4):
R
WADJ
= V
WADJ,th
× (I
Q
/I
WADJ
)/I
Q,act
(4)
Definitions:
•
V
WADJ,th
= switch off threshold, typical 1.35 V
•
I
Q
/I
WADJ
= current ratio, typical 720
•
I
Q,act
= switch off load current
Figure 7
AES03072
Band-Gap-
Reference
GND
+
-
TLE 4278 G
Watchdog
active
HIGH
disabled
Watchdog
LOW
WADJ
R
WADJ
Ι
Q