tle4678 Infineon Technologies Corporation, tle4678 Datasheet - Page 21

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

Figure 8
Figure 9
The watchdog output “WO” is an open collector output with an integrated pull-up resistor. In case a lower-ohmic
“WO” signal is desired, an external pull-up resistor to the output “Q” can be connected. Since the maximum “WO”
sink current is limited, the optional external resistor
sink current (see
Watchdog Input “WI”
The watchdog is triggered by an positive edge at the watchdog input “WI”. The signal is filtered by a bandpass
filter and therefore its amplitude and slope has to comply with the specification
details on the test pulse applied, see
Figure 10
Datasheet
(optional)
R
WADJ ,ext
Supply
Block Diagram Watchdog Circuit
Watchdog Output “WO”
Test Pulses Watchdog Input WI
WADJ
I
WI
Item 8.2.15
V
V
V
WI,hi
WI,lo
Detect
Edge
WI
GND
Control
R
and
d
WADJ ,int
V
WI
OR
/ d
Item
t
Figure
I
WADJ
S
R
8.2.16).
1
V
Supply
WADJ,th
V
Int.
DW,hi
10.
t
WI,p
I
I
DW ,dsch
D,ch
R
WO,ext
21
t
needs to be sized to comply with the watchdog output
V
DW
D
C
D
V
V
V
WI,hi
WI,lo
WI
BlockDiagram _WatchdogAdjust .vsd
&
R
WO
1 /
Item 8.2.10
f
WO
WI
Q
I
WO
t
C
WI
Rev. 1.0, 2008-07-31
Watchdog Function
Q
to
Item
I
Q
Controller
TLE4678
VDD
Reset
I/O
8.2.14. For
Micro-
GND