TLE9221SX Datasheet, PDF (11/91 Pages) Infineon Technologies AG – FlexRay Transceiver

TLE9221SX
Overview Functional Blocks
5
Overview Functional Blocks
5.1
Transmitter
The Transmitter is the output driver for the FlexRay bus. It is based on a “high” side and “low” side push-pull unit.
The push-pull units are supplied by the power supply uV_CC (see Figure 4).
While driving a “Data_1” or “Data_0” signal on to the FlexRay bus, the transceiver is active and enabled. During
an “Idle” signal, the transceiver is turned off.
uV_CC
BP
Driver
Overtemp.
Sensor
uV_CC
BM
Driver
time-out
Communication
Controller Interface
Figure 4 Block diagram of the Transmitter
The Transmitter is protected by an internal temperature sensor against overheating in terms of a short circuit on
the bus lines BM or BP. The Transmitter is controlled by the Communication Controller Interface (see
Chapter 5.3). The Transmitter is only active in BD_Normal mode.
5.2
Receiver
The Receiver detects communication elements, like “Idle”, “Data_1” and “Data_0”, when it is not in low power
mode. It is connected to the BP and BM I/O pins of the TLE9221SX, together with the Transmitter, the Bus-Failure
Detector, and the Wake-up Detector (see Figure 2). Based on a digital sampling concept, the Receiver is
optimized to withstand the RF immunity requirements of the automotive industry.
The low pass input filter is tailored to support analog bit times down to 60 ns. Data bits below 60 ns may not be
detected as valid communication elements. When the Receiver detects activity on the FlexRay bus behind the
input filter, the differential Receiver distinguishes whether “Data_0” or “Data_1” is signaled by the differential bus
voltage. The bus activity information is provided to the Bus Guardian Interface. The information regarding the
FlexRay data bits is provided to the Communication Controller (see Figure 5).
The thresholds and the timings of the Receiver are available in Figure 44 and Figure 45.
Data Sheet
11
Rev. 1.10, 2013-07-15