TLE7259-2GU Datasheet, PDF (7/31 Pages) Infineon Technologies AG – LIN Transceiver

TLE7259-2GU
Functional Description
4
Functional Description
The LIN Bus is a single wire, bi-directional bus, used for in-vehicle networks. The LIN Transceiver TLE7259-2GU
is the interface between the microcontroller and the physical LIN Bus (see Figure 15 and Figure 16). The logical
values of the microcontroller are driven to the LIN bus via the TxD input of the TLE7259-2GU. The transmit data
stream on the TxD input is converted to a LIN bus signal with optimized slew rate to minimize the EME level off
the LIN network. The RxD output reads 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 TxD input of the TLE7259-2GU to “Low” the transceiver
generates a dominant level on the BUS interface pin. The RxD output reads back the signal on the LIN bus and
indicates a dominant LIN bus signal with a logical “Low” to the microcontroller. Setting the TXD pin to “High” the
transceiver TLE7259-2GU sets the LIN interface pin BUS, to the recessive level, at the same time the recessive
level on the LIN bus is indicated by a logical “High” on the RxD output.
Every LIN network consists of a master node and one or more slave nodes. To configure the TLE7259-2GU for
master node applications, a resistor of 1 kΩ and a reverse diode must be connected between the LIN bus and the
power supply V_S or the INH pin of the TLE7259-2GU (see Figure 15 and Figure 16).
V_IO
TxD
Recessive
Dominant
Recessive
V_S
Recessive
BUS
Dominant
t
Recessive
V_IO
RxD
Recessive
Figure 3 LIN bus signals
Dominant
t
Recessive
Data Sheet
7
Rev. 1.1, 2008-07-14