MC33989PEG Freescale Semiconductor, MC33989PEG Datasheet - Page 44

• Manufacturer Part Number: MC33989PEG
• Description: SBC-HS
• Manufacturer: Freescale Semiconductor

TYPICAL APPLICATIONS
SUPPLEMENTAL APPLICATION NOTES
Power Up and V
for instance by an over-current or short-circuit (ex short to 4.0 V), and if the low power mode previously selected was sleep mode
and if the BATFAIL flag has been cleared, the SBC enters reset mode for a time period of 100 ms. The pin WD stays high, but
the high level (V
V
mode.
WAKE-UP TIMINGS — SLEEP MODE
wake-up time described is the time from the wake-up event to the SBC reset pin release. The wake-up time is the sum of several
timings: wake-up signal detection, V
reset time, the reset pin goes from low to high and the MCU is ready to start software operations.
44
33989
SPI (CS)
DD1
VDD1
WD
RST
INT
The first part of the graph is the same as the previous figure. If V
The paragraphs below describe the wake-up events from Sleep mode, and the sequence of the signals at the SBC level. The
SPI (CS)
VDD1
WD
RST
INT
and V2 are off (The following figure is an example where V
S B C in
R E S E T
m o d e
Figure 25. Power up and V
Figure 24. Power Up and V
SBC in
RESET
mode
OH
DD1
) follows the V
350 ms
Going Low with Sleep Mode as Default Low Power Mode Selected
Reset every 350 ms
S B C in N o rm a l re q u e s t
m o d e
Reset every 350 ms
350 ms
SBC in Normal request
mode
DD1
DD1
level.The reset and interrupt pins are low. After the 100 ms, the SBC goes into Sleep mode.
regulator start-up and decoupling capacitor charge, and reset time. At the end of the
DD1
DD1
Going Low with Sleep Mode as Default Low Power Mode Selected
Going Low with Stop Mode as Default Low Power Mode Selected
S B C in N o rm a l
m o d e
SBC in Normal
mode
Write Watchdog
Write Watchdog
DD1
each X ms
each X ms
DD1
is shorted to 4.0 V, and after 100 ms the SBC enters sleep
is pulled below the V
S B C in R e s e t
m o d e
(B A T F A IL fla g
m u s t b e c le a re d )
SBC in Reset
mode
1 0 0 m s
Watchdog period
No problem on
S B C in S le e p m o d e
Analog Integrated Circuit Device Data
Watchdog period
No problem on
DD1
under-voltage reset (typ 4.6 V)
Freescale Semiconductor
SBC in Normal
Request mode
350 ms