TLE7269G Datasheet, PDF (17/34 Pages) Infineon Technologies AG – Twin LIN Transceiver

TLE7269G
Functional Description
In Stand-By mode the RxD1 pin signals the low power supply condition with a “High” signal. A logical “High” on
the EN pin changes the operation mode back to Normal Operation mode.
In case the supply voltage V_S is dropping below the specified operation range (see Table 5), the TLE7269G
disables the output and receiver stages. This feature secures the communication on the LIN bus. If the power
supply V_S reaches a higher level as the Under-Voltage level V_S > V_S,UV,BLK the TLE7269G continues with normal
operation. A mode change only applies if the power supply V_S drops below the power on reset level (V_S <
V_S,UV,PON).
If the power supply V_IO drops below the Under-Voltage level V_IO > V_IO,UV the output and receiver stages will be
disabled as well. When V_IO reaches a higher level as the Under-Voltage V_IO > V_IO,UV level the TLE7269G continues
with normal operation and data transmission.
4.11
TxD Time Out function
If the TxD1 or TxD2 signal is dominant for a time t > t_timeout the TxD time-out function deactivates the transmission
of the LIN signal to the bus and disables both, the output stage 1 and the output stage 2. This is realized to prevent
the bus from being blocked by a permanent “Low” signal on the TxD1 or TxD2 pin, caused by an error on the
external microcontroller (see Figure 12).
The transmission is released again, after a rising edge at TxD1 or TxD2 has been detected.
TxD Time-Out due to
microcontroller error
Normal Communication
t_timeout
TxD1
Recovery of the
microcontroller error
t_torec
Release after TxD
Time-out
Normal Communication
t
BUS1
TxD2
TxD Time-Out due to
microcontroller error
Normal Communication
t_timeout
t
Recovery of the
microcontroller error
t_torec
Release after TxD
Time-out
Normal Communication
t
BUS2
Figure 12 TxD Time-Out function
Data Sheet
17
t
Rev. 1.2, 2007-11-13