TLE7258D_15 Datasheet, PDF (9/31 Pages) Infineon Technologies AG – TLE7258D

TLE7258D
Functional Description
While the TLE7258D is in Normal Operation mode the following functions are available:
• The transmitter is turned on; data on the TxD input are driven on the LIN bus.
• The receiver is turned on; data on the LIN bus are monitored and signaled on the RxD output.
• The BUS pin is terminated to V_S via the internal termination resistor R_BUS (see Figure 1).
• The TxD input is pulled up via a current source to the internal power supply of the TLE7258D.
• The bus wake-up comparator is turned off.
• The two-level undervoltage detection is active. In case V_S drops below the undervoltage detection level the
TLE7258D blocks the transmitter and receiver. In case V_S drops below the power-on reset level V_S,UV,PON the
TLE7258D changes the operation mode to Standby mode after recovery (see “Undervoltage Detection” on
Page 15).
• The EN input is active. A “low” signal on the EN input triggers a transition to Sleep.
After a mode change to Normal Operation the TLE7258D requires a logical “high” signal for the time t_to,rec on the
TxD input before releasing the data communication (see Figure 5). The transmitter remains deactivated as long
as the signal on the TxD input remains logical “low”, preventing possible bus communication disturbance.
4.3
Standby Mode
The Standby mode is entered automatically after:
• A power-up event on the supply V_S.
• A bus wake-up event.
• A power-on reset caused by the supply V_S.
In Standby mode no communication to the LIN bus is possible. The transmitter and the receiver are disabled.
While the TLE7258D is in Standby mode the following functions are available:
• The transmitter is turned off, the TxD input is inactive and the bus output is permanent “recessive”.
• The receiver is turned off.
• The RxD output indicates either a wake-up event or a power-up event (see Figure 4 and Table 1).
• The BUS pin is terminated to V_S via the internal termination resistor R_BUS (see Figure 1).
• The TxD input is pulled up with a current source to the internal power supply of the TLE7258D.
• In Standby mode only the power-on reset level of the undervoltage detection is active (see “Undervoltage
Detection” on Page 15).
• The EN input is active. A “high” signal on the EN input triggers a transition to Normal Operation mode (see
Figure 5).
After a power-up event the TLE7258D enters Standby mode by default. The EN pin has an internal pull-down
resistor and the TLE7258D remains in Standby until the external microcontroller applies a logical “high” signal at
the EN input (see Figure 6).
Data Sheet
9
Rev. 1.2, 2014-12-08