TLE7259G

Functional Description

Data Sheet

5

Rev 2.1, 2007-04-27

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

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 k

Ω and a reverse diode must be connected between the LIN bus

and the power supply

V

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.

Figure 3

Operation Mode State Diagram

AEA03514.VSD

Power-Up

Wake Up

via Bus:

wake,bus

via Wake:

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 k

EN

Normal Mode

High

High

INH

EN

Sleep Mode

Low

Floating

INH

Stand-By

INH

EN

RxD

TxD

Low

High

EN

High

Low

EN

High

EN