TLE9221SX Datasheet, PDF (24/91 Pages) Infineon Technologies AG – FlexRay Transceiver

TLE9221SX
Wake-up Detector
7
Wake-up Detector
The FlexRay transceiver TLE9221SX can detect different wake-up events via the central Wake-up Detector.
These can be either remote wake-up events provided by the FlexRay bus or local wake-up events provided to the
local wake-up pin WAKE.
Wake-up events are clearly defined by the FlexRay EPL, version 3.0.1. Wake-up signals that are not compliant
with the FlexRay EPL, version 3.0.1, shall not be considered as a wake-up signal and are blocked by the Wake-
up Detector.
Wake-up signals compliant with the FlexRay EPL, version 3.0.1, are:
• A falling edge at the local wake-up pin WAKE (see Chapter 7.1.1).
• A rising edge at the local wake-up pin WAKE (see Chapter 7.1.2).
• A dedicated wake-up pattern at the FlexRay bus (see Chapter 7.2.1 and Chapter 7.2.2).
• A wake-up pattern implemented in a standard FlexRay frame (see Chapter 7.2.3).
The Wake-up Detector is active in every mode of operation and works over the entire operating range as long as
uV_BAT is in its functional range (see Table 19).
Detected wake-up events are analyzed by the Central State Machine and are compared with the overall device
status. They may cause a change of the operation mode (details see Chapter 9.5) and they may set a wake-up
flag or a wake-up bit (details see Chapter 7.3).
7.1
Local Wake-up
The TLE9221SX provides a local wake-up input WAKE, tailored to withstand voltages up to uV_BAT(Max). Positive
and negative signal changes on the WAKE pin trigger the Wake-up Detector.
The WAKE input is provided with an internal pull-up and pull-down structure and an internal wake pulse filter (see
Figure 14).
V_BAT
iBDWake_H
Wake-Up
Detector
Wake Pulse Filter
(dBDWakePulseFilter)
iBDWake_Thr
WAKE
iBDWake_L
GND
Figure 14 Block diagram of the WAKE input
Depending on the signal at the WAKE input, either the pull-up structure or the pull-down structure is connected to
the WAKE input. While a voltage uV_WAKE > uBDWake_Thr is applied to the WAKE input, the internal pull-up structure
Data Sheet
24
Rev. 1.10, 2013-07-15