TLE9221SX Datasheet, PDF (15/91 Pages) Infineon Technologies AG – FlexRay Transceiver

Central
State
Machine
Transmitter
Receiver
TLE9221SX
Overview Functional Blocks
uV_IO
BGE
uV_IO
RxEN
Figure 8 Block diagram of the Bus Guardian Interface
The BGE input is an additional fail safe input, allowing external hardware to block the data stream driven to the
FlexRay bus medium. Switching the BGE input to logical “low” disables the Transmitter of TLE9221SX regardless
of the signals on all the other digital input pins. The BGE input is active only in BD_Normal mode (see Table 4 and
Figure 7).
Table 4 TxD/TxEN interface, acting as a Transmitter
Mode of Operation TxEN BGE TxD
BD_Normal
“high” X¹⁾
X
Resulting Signal on the Bus
“Idle”
X
“low” X
“Idle”
“low” “high” “low” “Data_0”
“low” “high” “high” “Data_1”
All other modes
X
X
X
“Idle”
1) X = don’t care
The RxEN (Receive Enable Not) indicates the activity on the FlexRay bus. In case the FlexRay bus is “Idle”, the
logical signal on the RxEN is “high”. Any active data signal on the FlexRay bus, regardless of whether it is “Data_0”
or “Data_1”, is indicated by a logical “low” signal on the RxEN output pin. Like the RxD output pin, the RxEN output
pin indicates also the wake-up flag while the transceiver is in low power mode (see Table 5 and Figure 7).
Data Sheet
15
Rev. 1.10, 2013-07-15