Freescale Semiconductor StarterTRAK USB for Automotive Safety Applications TRK-USB-MPC5643L TRK-USB-MPC5643L 数据表
产品代码
TRK-USB-MPC5643L
Electrical characteristics
MPC5643L Microcontroller Data Sheet, Rev. 9
Freescale Semiconductor
107
Figure 18. Reset sequence start via RESET assertion
3.19.5
External watchdog window
If the application design requires the use of an external watchdog the data provided in
to determine the correct positioning of the trigger window for the external watchdog.
shows the relationships between
the minimum and the maximum duration of a given reset sequence and the position of an external watchdog trigger window.
Figure 19. Reset sequence - External watchdog trigger window position
3.20
AC timing characteristics
AC Test Timing Conditions: Unless otherwise noted, all test conditions are as follows:
• TJ = –40 to 150 C
• Supply voltages as specified in
• TJ = –40 to 150 C
• Supply voltages as specified in
T
Reset, max
starts here
T
Reset, min
starts here
RESET_B
0.65 * VDD_HV_IO
t
V
0.35 * VDD_HV_IO
RESET
External Watchdog Window Closed
Earliest
Application
Start
Application
Start
Latest
Application
Start
Application
Start
Internal Reset Sequence
Start condition (signal or voltage rail)
External Watchdog Window Open
T
Reset, min
T
Reset, max
T
WDStart, min
T
WDStart, max
External Watchdog Window Closed
External Watchdog Window Open
Basic Application Init
Basic Application Init
Application time required to
prepare watchdog trigger
prepare watchdog trigger
Watchdog needs to be triggered within this window
Watchdog trigger
Application Running
Application Running