TLE6251-2G Datasheet, PDF (15/35 Pages) Infineon Technologies AG – High Speed CAN-Transceiver with Wake and Failure Detection

TLE6251-2G
Wake - Up Functions
6.2
Local Wake - Up
The TLE6251-2G can be activated from Sleep Mode by a signal change on the WK pin, also called local Wake -
Up. Designed to withstand voltages up to 40V the WK pin can be directly connected to V_S. The internal logic on
the WK pin works bi-sensitive, meaning the Wake - Up logic on the pin WK triggers on a both signal changes, from
“High” to “Low” and from “Low” to “High” (see Figure 7).
V_WK
t < t_Wk(local)
No Wake-Up
t > t_Wk(local)
Wake-Up
V_WK,H
INH
Sleep Mode
t
t
Stand-By Mode
V_WK
INH
t < t_Wk(local)
No Wake-Up
t > t_Wk(local)
V_WK,L
Wake-Up
t
Sleep Mode
Sleep Mode
t
Stand-By Mode
Stand-By Mode
Figure 7 Local Wake - Up
A filter time t_WK(local) is implemented to protect the TLE6251-2G against unintended Wake - Up’s, caused by spikes
on the pin WK. The threshold values V_WK,H and V_WK,L depend on the level of the V_S power supply.
In Stand-By mode the RxD output pin and the NERR output pin display the CAN bus Wake - Up event by a logical
“Low” signal (Details see Chapter 8). Once the HS CAN Transceiver TLE6251-2G has recognized the Wake - Up
event and has changed to Stand-By Mode, the INH output pin becomes active and provides the voltage V_S to the
external circuitry.
Data Sheet
15
Rev. 1.0, 2009-05-07