TLE9222 datasheet(39/43 Pages) INFINEON

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Data Sheet

Rev. 1.2

2017-10-17

TLE9222

FlexRay Transceiver

Application information

trigger a SPI readout of the status register. By observing the BGE flag being set “low”, the MCU has verified that

the TLE9222 has been safely disconnected from the bus by the Safety Supply IC.

It is recommended to follow these steps for the ECU software implementation. After ECU power-up, the MCU

should test and verify the correct behavior of the fail safe state as a part of its initialization routine, before

releasing the transceiver for bus access and transmission.

7.5

Minimizing ECU current consumption through BD_Standby mode

The very low current consumption of iVCC_Stb_85 and iVCC_Stb_150 of the TLE9222 can only be reached with the

correct system implementation and software control. While operating in ECU low power mode with the

TLE9222 in BD_Standby mode, the logic inputs should be in their default states (See Table 2). This prevents

current to flow through the implemented pull-up / pull-down circuits. Secondly, the logic outputs, RxD and

ERRN, should be in their default condition “high” for BD_Standby mode (See Table 4). After the TLE9222 is set

to BD_Standby mode, it is recommended to perform a SPI readout for verifying correct state transition and to

clear pending diagnosis flags.

A MCU in low-power mode should continuously (by interrupt) or periodically (by polling) monitor the ERRN

output for wake-up information. Even if the wake-up function is not being used, the MCU should clear the flags

of the status register by SPI readout. For simpler ECU implementations, not using the SPI interface, a mode

change cycle to BD_Normal mode and back to BD_Standby mode again has the same effect.

7.6

Further application information

• Please contact us for information regarding the pin FMEA

• For further information you may contact http://www.infineon.com/

TLE9222 Datasheet(PDF) 39 Page - Infineon Technologies AG