TLE7269G Datasheet, PDF (7/34 Pages) Infineon Technologies AG – Twin LIN Transceiver

TLE7269G
Functional Description
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Functional Description
The LIN Bus is a single wire, bi-directional bus, used for in-vehicle networks. The LIN Transceiver TLE7269G is
the interface between the microcontroller and the physical LIN Bus (see Figure 17 and Figure 18). The logical
values of the microcontroller are driven to the LIN bus via the TxD inputs of the TLE7269G. The transmit data
stream on the TxD input is converted to a LIN bus signal with optimized slew rate to minimize the EME level of the
LIN network. The RxD outputs read back the information from the LIN bus to the microcontroller. The receiver has
an integrated filter network to suppress noise on the LIN Bus and to increase the EMI (Electro Magnetic Immunity)
level of the transceiver.
Two logical states are possible on the LIN bus according to the LIN Specification 2.1 (see Figure 3):
In dominant state, the voltage on the LIN bus is set to the GND level. In recessive state, the voltage on the LIN
bus is set to the supply voltage V_S. By setting the TxD1, TxD2 inputs of the TLE7269G to “Low” the transceiver
generates a dominant level on the BUS1, BUS2 LIN interface pins. The RxD1, RxD2 outputs read back the signal
on the LIN bus and indicate a dominant signal on the LIN bus with a logical “Low” to the microcontroller. Setting
the TXD1, TxD2 pins to “High” the transceiver TLE7269G sets the BUS1, BUS2 LIN interface pins to recessive
level, at the same time the recessive level on the LIN bus is indicated by a logical “High” on the RxD1, RxD2
outputs.
Every LIN network consists of a master node and one or more slave nodes. To configure the TLE7269G for master
node applications, a resistor in the range of 1 kΩ and a reverse diode must be connected between the LIN bus
and the power supply V_S or between the LIN bus and INH pin of the TLE7269G (see Figure 17 and Figure 18).
Both integrated transceivers can operate independent from each other and several operation modes and Wake-
Up functions are implemented. The bus Wake-Up function of the transceiver 2 can be turned off via the W2O pin.
V_IO
TxD1
TxD2
Recessive
Dominant
Recessive
t
V_S
BUS1
BUS2
Recessive
Dominant
Recessive
V_IO
RxD1
RxD2
Recessive
Figure 3 LIN bus signals
Data Sheet
Dominant
t
Recessive
t
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Rev. 1.2, 2007-11-13