Data Sheet

9

Rev. 1.2, 2007-11-13

TLE7269G

Functional Description

The TLE7269G has 3 major operation modes:

•

Stand-By mode

•

Normal Operation mode

•

Sleep mode

The Normal Operation mode contains 3 sub-operation modes, which differentiate by the slew rate control of the

LIN Bus signal (see Figure 4).

Sub-operation modes with different slew rates on the BUS1,BUS2 pins:

•

Low Slope mode, for data transmission rates up to 10.4 kBaud

•

Normal Slope mode, for data transmission rates up to 20 kBaud

•

Flash mode, for programming of the external microcontroller

The TLE7269G contains 2 separate LIN transceivers, which are able to operate in two independent LIN networks

with two different data transmission rates. The operation mode of the TLE7269G is selected by the EN pin and the

TxD1 pin. Selecting the operation mode applies to the whole device. Transceiver1 and transceiver2 are always

set to the same operation mode and sub-operation mode (see Figure 4).

4.2

Normal Operation Mode

The TLE7269G enters the Normal Operation mode after the microcontroller sets EN to “High” (see Figure 4). In

Normal Operation mode both LIN bus receivers and both LIN bus transmitters are active. Data from the

microcontroller is transmitted to the LIN bus1 or LIN bus2 via the TxD1 or TxD2 pin, the receiver detects the data

stream on the LIN bus1 or bus2 and forwards it to the RxD1 or RxD2 output pins. In Normal Operation mode, the

INH1 pin and the INH2 are “High” (set to

V

Normal Slope mode, Low Slope mode and the Flash mode are Normal Operation modes and in these sub-modes

the behavior of the INH pin and the bus termination is the same. To set the device into one of these 3 sub-modes

the TxD1 pin and the EN pin are used for the sub-operation mode selection. In order to avoid any bus disturbance

during a mode change, the output stages of the TLE7269G are disabled and set to recessive state during the

mode change procedure. To release the TLE7269G for data communication on the LIN bus1 and LIN bus2, the

TxD1 and TxD2 pins need to be set to “High” for the time

t

Table 2

Operating modes

Mode

EN

INH1

INH2

TxD1

TXD2

RxD1

RxD2

LIN Bus

Termination

Comments

Sleep

Low

Floating Low

High

resistive

High

Impedance

No Wake-Up request detected

Stand-By Low

High

Low

High2)

Low

1) To indicate the Wake-Up sources via the RxD pins the power supply

V

30 k

Ω

(typical)

RxD1 “Low” after local or bus Wake-Up (BUS 1,

BUS 2)

RxD2 “Low” after bus Wake-Up on Bus2. RxD2

“High” on all other Wake-Up and Power-Up events.

RxD1 “High” after Power-Up

TxD1 strong pull down after local Wake-Up (WK

TxD1 weak pull down after bus Wake-Up (BUS1,

BUS2) or Power-Up2)

2) The TxD1 input needs an external termination to indicate a “High” or a “Low” signal. The external termination could be a

pull-up resistor or an active microcontroller output.

Normal

Operation

High

High

Low

High

Low

High

30 k

Ω

(typical)

RxD1, RxD2 reflects the signal on the BUS1,

BUS2

TxD1,TxD2 driven by the microcontroller