908E621_12 Datasheet, PDF (24/60 Pages) Freescale Semiconductor, Inc – Integrated Quad Half bridge and Triple High Side Embedded MCU and LIN for High End Mirror

FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
908E621 ANALOG DIE MODES OF OPERATION
The 908E621 offers three operating modes: Normal (Run),
Stop, and Sleep. In Normal mode, the device is active and is
operating under normal application conditions. The Stop and
Sleep modes are low power modes with wake-up capabilities.
The different modes can be selected by the STOP and
SLEEP bits in the System Control Register.
Figure 11 describes how transitions are done between the
different operating modes and Table 6, page 26, gives an
overview of the operating modes.
Power
Down
Power Up
RESET
VDD High and Reset Delay (tRST) expired
Normal
Request
VDD Low
PSON = 0 and Normal Request
timeout (tNORMREQ) expired
Reset (LVR, HTR, WDR, ext. Reset)
NORMAL
SLEEP Command
Wake-up (Reset)
Reset (LVR, ext. Reset)
SLEEP
STOP
Reset (LVR, ext. Reset, (HTR))
Figure 11. Operating Modes and Transitions
Normal Mode
This Mode is the normal operating mode of the device, all
functions and power stages are active and can be enabled/
disabled. The voltage regulator provides the +5.0 V V_DD to
the MCU.
After a reset (e.g. Power-On-Reset, Wake-up from Sleep),
the MCU has to set the PSON bit in the System Control
Register within 80 ms typical (t_NORMREQ). This is to ensure
the MCU has started up and is operating correctly. If the
PSON bit is not set within the required time frame, the device
enters SLEEP mode to reduce power consumption (fail safe).
This MCU monitoring can be disabled (e.g. for
programming) by applying V_DD on the TESTMODE pin.
Stop Mode
In Stop mode, the voltage regulator still supplies the MCU
with V_DD (limited current capability). To enter the Stop mode,
the STOP bit in the System Control Register must be set, and
the MCU has to be stopped also (see 908EY16 datasheet for
details).
Wake-up from this mode is possible by the LIN bus activity
or the wake-up input L0. It is maskable with the LINIE and/or
L0IE bits in the Interrupt Mask Register. The analog die is
generating an interrupt on IRQ_A pin to wake-up the MCU.
The wake-up / interrupt source can be evaluated with the
L0IF and LINIF bits in the Interrupt Flag Register.
Stop mode has a higher current consumption than Sleep
mode, but allows a quicker wake-up. Additionally the wake-
908E621
24
Analog Integrated Circuit Device Data
Freescale Semiconductor