TLE7259G_07 Datasheet, PDF (5/27 Pages) Infineon Technologies AG – LIN Transceiver

TLE7259G
Functional Description
4
Functional Description
The LIN Bus is a single wire, bi-directional bus, used for in-vehicle networks. The LIN Transceiver TLE7259G is
the interface between the micro controller and the physical LIN Bus (see Figure 11 and Figure 12). The logical
values of the micro controller are driven to the LIN bus via the TxD input of the TLE7259G. The transmit data
stream on the TxD input is converted to a LIN bus signal with optimized slew rate to minimize the EME level on
the LIN bus. The RxD output reads back the information from the LIN bus to the micro controller, regardless of the
logical value of the TxD input. The receiver has an integrated filter network to suppress noise on the LIN Bus and
to increase the EMI level of the transceiver. Two logical states are possible on the LIN bus according to the LIN
Specification 2.1. The dominate state (voltage near ground) on the LIN bus represents a “logic 0“ on the TxD input
of the TLE7259G; the recessive state (voltage near supply voltage V_S) represents a “logic 1” on the TxD input (see
timing diagram Figure 9).
Every LIN network consists of a master node and one or more slave nodes. To configure the TLE7259G 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 the INH pin of the TLE7259G (see Figure 11 and Figure 12).
4.1
Operating Modes
The TLE7259G has 3 different operation modes. After a power-up event the TLE7259G starts from the Stand-By
mode. By setting the EN pin to “logic 1“ the micro controller can change the mode into Normal-Operation mode.
Power-Up
Normal Mode
EN
INH
High
High
EN High
EN Low
EN High
Stand-By
EN RxD
Low Low ¹⁾
Floating ²⁾
TxD
Low ³⁾
High ⁴⁾
INH
High
Sleep Mode
EN
INH
Low Floating
Wake Up
via Bus: t > t_wake,bus
via Wake: t > t_wake
1) After wake up (via Bus or Wake)
2) After start up
3) After wake up via Wake (internal strong pull down, > 1.9 mA)
4) After wake up via Bus (internal weak pull down, 350 kΩ )
Figure 3 Operation Mode State Diagram
Data Sheet
5
AEA03514.VSD
Rev 2.1, 2007-04-27