TLE 6363 Infineon Technologies, TLE 6363 Datasheet - Page 13

• Manufacturer Part Number: TLE 6363
• Manufacturer: Infineon Technologies

Specifications of TLE 6363

• Packages: P-DSO-14
• Comment: Please use RoHS compliant TLE6711
• Vq (max): 5.0V
• Iq (max): 250.0 mA
• Iq (typ): 1,500.0 µA
• Output: Boost/Buck Conv.

TLE 6363
Watchdog Operation
The watchdog uses one hundred of the oscillator’s clock signal period as a timebase,
t
defined as the watchdog cycle time
.
CYL
After power-on, the reset output signal at the RO pin (microcontroller reset) is kept LOW
t
for the reset delay time
, i.e. 64 cycles. With the LOW to HIGH transition of the signal
RD
t
at RO the device starts the closed window time
= 32 cycles. A trigger signal within
CW
this window is interpreted as a pretrigger failure according to the figures shown below.
t
After the closed window the open window with the duration
is started. The open
OW
t
window lasts at minimum until the trigger process has occurred, at maximum
is
OW
32 cycles.
A HIGH to LOW transition of the watchdog trigger signal on pin WDI is taken by a trigger.
To avoid wrong triggering due to parasitic glitches two HIGH samples followed by two
t
LOW samples (sample period
) are decoded as a valid trigger. If a trigger signal
CYL
appears at the watchdog input pin WDI during the open window or a power up/down
occurs, the watchdog window signal is reset and a new closed window follows.
A reset is generated (RO goes LOW) if there is no trigger pulse during the open window
or if a pretrigger occurs during the closed window. This reset happens after 64 cycles
after the latest valid closed window start time and lasts for further 64 cycles.
The triggering is correct also, if the first three samples (two HIGH one LOW) of the trigger
pulse at pin WDI are inside the closed window and only the fourth sample (the second
LOW sample) is taken in the open window.
In addition to the microcontroller reset signal RO the device generates a system enable
signal at pin SEN. If RO is HIGH the system enable goes active HIGH with the first valid
watchdog trigger pulse at pin WDI. The SEN output goes LOW immediately if a
pretrigger, a missing trigger or a power down reset occurs.
Data Sheet Rev. 1.2
13
2003-06-02