tle4678 Infineon Technologies Corporation, tle4678 Datasheet - Page 22

• Manufacturer Part Number: tle4678
• Description: Low Drop Out Linear Voltage Regulator 5 V Fixed Output Voltage
• Manufacturer: Infineon Technologies Corporation

Watchdog Timing
Positive edges at the watchdog input pin “WI” are expected within the watchdog trigger time frame
a low signal at pin “WO” is generated. If a watchdog low signal at pin “WO” is generated, it remains low for
All watchdog timings are defined by charging and discharging the capacitor
timing can be programmed by selecting
In case a watchdog trigger time period
capacitor’s value can be derived from the specified value given in
The watchdog output low time
The formula is valid for
Figure 11
Datasheet
V
WO,low
C
t
t
WD,lo
WD,p
V
V
D
V
V
DW,hi
DW,lo
V
V
WI,hi
WI,lo
V
WO
= 100nF
WI
D
=
=
Timing Diagram Watchdog
t
t
WI,tr
WD,lo,100nF
+
t
t
WD,lo
C
WI,tr
D
/
C
10nF. For precise timing calculations consider also the delay capacitor’s tolerance.
t
D
t
WI,tr,100nF
WD,lo
/ 100nF
and the watchdog period
C
D
t
. For timing details see also
WI,tr
No positive
different from the value for
V
WI
edge
22
t
WD,lo
t
WD,p
Item
then becomes:
t
WI,tr
outside spec
d
Figure
8.2.22:
V
WI
/ d
t
C
C
11.
D
D
t
WD,lo
= 100nF is required, the delay
T
at pin “D”. Thus, the watchdog
WI,p
1/
f
WI
T i mi n g Di a g ra m_ W a t ch d o g .vsd
Rev. 1.0, 2008-07-31
Watchdog Function
t
WI,p
t
WI,tr
TLE4678
, otherwise
t
t
t
t
WD,lo
(10)
(8)
(9)
.