TLE7269G Datasheet, PDF (9/34 Pages) Infineon Technologies AG – Twin LIN Transceiver

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).
Table 2 Operating modes
Mode
EN INH1
INH2
TxD1 RxD1
TXD2 RxD2
LIN Bus Comments
Termination
Sleep
Low Floating Low
High High
No Wake-Up request detected
resistive Impedance
Stand-By Low High
Low Low
30 kΩ
High²⁾ High ¹⁾ (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
pin)²⁾
TxD1 weak pull down after bus Wake-Up (BUS1,
BUS2) or Power-Up²⁾
Normal High High Low Low
30 kΩ
RxD1, RxD2 reflects the signal on the BUS1,
Operation
High High (typical)
BUS2
TxD1,TxD2 driven by the microcontroller
1) To indicate the Wake-Up sources via the RxD pins the power supply V_IO has to be present
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.
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_S) and the bus termination is set to 30 kΩ for both integrated transceivers.
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_to,rec.
Data Sheet
9
Rev. 1.2, 2007-11-13