TLE9221SX Datasheet, PDF (56/91 Pages) Infineon Technologies AG – FlexRay Transceiver

TLE9221SX
Operating Mode Description
9.5
Operation Mode Changes by the Wake-up Flag
Setting the wake-up flag triggers a mode change to BD_Standby mode, regardless of the transceiver being in
BD_Sleep mode or in the BD_GoToSleep command. While the transceiver TLE9221SX remains in BD_Standby
mode, a wake-up event sets the wake-up bit and the wake-up flag. The wake-up flag is indicated at the ERRN,
RxD and RxEN outputs. No mode change by the wake-up event is applied (for details see Figure 37 and
Table 16).
The wake-up flag can be set only in BD_Sleep mode, BD Standby mode or while the BD_GoToSleep command
is being executed (for details see “Wake-up Flag and Wake-up Bits” on Page 29).
While the wake-up flag is active, the FlexRay transceiver TLE9221SX cannot change over to BD_Sleep mode
again (see Figure 34). To reset the wake-up flag, either change the operating mode of the TLE9221SX to
BD_Normal mode or read out the SIR.
BD_GoToSleep
STBN
EN
65
L
H
INH
Not_Sleep
BD_Standby
STBN
EN
64
L
L
INH
Not_Sleep
62
63
BD_Sleep
STBN
EN
L
H
INH
Sleep
Figure 37 Operating mode change by wake-up flag
Setting the wake-up flag triggers not only a change in the operating mode, but also clears all undervoltage flags.
The undervoltage bits available in the SIR remain active.
In case the undervoltage event remains present, setting the wake-up flag clears the undervoltage flag. The
undervoltage detection timer is restarted and the undervoltage flag is set again when the undervoltage detection
timer expires.
Note: Setting the wake-up flag clears only the undervoltage flag, not the undervoltage bit. The undervoltage bit
remains active and is visible in the SIR.
Data Sheet
56
Rev. 1.10, 2013-07-15