TLE7250_15 Datasheet, PDF (10/34 Pages) Infineon Technologies AG – High Speed CAN-Transceiver

TLE7250LE
TLE7250SJ
Functional Description
4.2
Modes of Operation
The TLE7250 supports three different modes of operation, power-save mode, receive-only mode and normal-
operating mode while the transceiver is supplied according to the specified functional range. The mode of
operation is selected by the NEN and the NRM input pins (see Figure 4).
NEN = 0
NRM = 1
V_CC > V_CC(UV,R)
power-save mode
NEN = 1 NRM = “X”
NEN = 1
NRM = “X”
NEN = 1
NRM = “X”
NEN = 0
NRM = 0
normal-operating mode
NEN = 0 NRM = 1
Figure 4
V_CC > V_CC(UV,R)
Mode state diagram
NEN = 0
NRM = 0
NEN = 0
NRM = 1
receive-only
mode
NEN = 0 NRM = 0
V_CC > V_CC(UV,R)
4.2.1 Normal-operating Mode
In normal-operating mode the transmitter and the receiver of the HS CAN transceiver TLE7250 are active (see
Figure 1). The HS CAN transceiver sends the serial data stream on the TxD input pin to the CAN bus. The data
on the CAN bus is displayed at the RxD pin simultaneously. A logical “low” signal on the NEN pin and a logical
“high” signal on the NRM pin selects the normal-operating mode, while the transceiver is supplied by V_CC (see
Table 2 for details).
4.2.2 Power-save Mode
The power-save mode is an idle mode of the TLE7250 with optimized power consumption. In power-save mode
the transmitter and the normal-mode receiver are turned off. The TLE7250 can not send any data to the HS CAN
bus nor receive any data from the HS CAN bus.
The RxD output pin is permanently “high” in the power-save mode.
A logical “high” signal on the NEN pin selects the power-save mode, while the transceiver is supplied by the
transmitter supply V_CC (see Table 2 for details).
In power-save mode the bus input pins are not biased. Therefore the CANH and CANL input pins are floating and
the HS CAN bus interface has a high resistance.
4.2.3 Receive-only Mode
In receive-only mode the normal-mode receiver is active and the transmitter is turned off. The TLE7250 can
receive data from the HS CAN bus, but cannot send any data to the HS CAN bus.
A logical “low” signal on the NEN pin and a logical “low” signal on the NRM pin selects the receive-only mode,
while the transceiver is supplied by V_CC (see Table 2 for details).
Data Sheet
10
Rev. 1.0, 2015-08-12