TLE7259-2GU Datasheet, PDF (10/31 Pages) Infineon Technologies AG – LIN Transceiver

TLE7259-2GU
Functional Description
4.2.1 Low Slope Mode
In Low Slope mode data transmission rates up to 10.4 kBauds are possible. Setting the EN pin to “High” starts the
transition to Low Slope mode. (see Figure 5).
The mode change to Low Slope mode is defined by the time t_MODE. The time t_MODE specifies the delay time between
the threshold, where the EN pin detects a “High” input signal, and the actual mode change of TLE7259-2GU into
Low Slope mode. Entering in Normal Operation mode, the TLE7259-2GU always enters per default into Low Slope
mode. The signal on the TxD pin is not relevant for entering into Low Slope mode.
Finally to release the data communication it is required to set the TxD pin to “High” for the time t_to,rec.
V_EN,ON
EN
Don’t care
TxD
t_MODE
Stand-By Mode / Sleep Mode
Data transmission
t_to,rec
Low Slope Mode
Figure 5 Timing to enter Low Slope Mode
.
4.2.2 Flash Mode
In Flash mode it is possible to transmit and receive LIN messages on the LIN bus. The slew rate control
mechanism of the LIN bus signal is disabled. This allows higher data transmission rates, disregarding the EMC
limitations of the LIN network. The Flash mode is intended to be used during the ECU production for programming
the microcontroller via the LIN bus interface.
The TLE7259-2GU can be set to Flash mode only from Low Slope mode (see Figure 4). Flash mode is entered
by setting the EN pin to “Low” for the time t_fl1 and generating a falling and a rising edge at the TxD pin with the
timing t_fl2, t_fl3 and t_fl4 (see Figure 6). Leaving the Flash mode by the same sequence, sets the TLE7259-2GU back
to Low Slope mode. Finally to release the data transmission it is required to set the TxD pin to “High” for the time
t_to,rec.
Additionally the TLE7259-2GU can leave the Flash mode as well by switching only the EN pin to “Low”. By
applying this “Low” signal to the EN pin the TLE7259-2GU is put into Sleep mode.
Data Sheet
10
Rev. 1.1, 2008-07-14