TLE7250_15 Datasheet, PDF (9/34 Pages) Infineon Technologies AG – High Speed CAN-Transceiver

TLE7250LE
TLE7250SJ
Functional Description
The TLE7250 is a High-Speed CAN transceiver, operating as an interface between the CAN controller and the
physical bus medium. A HS CAN network is a two wire, differential network which allows data transmission rates
for CAN FD frames up to 2 MBit/s. Characteristic for HS CAN networks are the two signal states on the HS CAN
bus: “dominant” and “recessive” (see Figure 3).
V_CC and GND are the supply pins for the TLE7250. The pins CANH and CANL are the interface to the HS CAN
bus and operate in both directions, as an input and as an output. RxD and TxD pins are the interface to the CAN
controller, the TxD pin is an input pin and the RxD pin is an output pin. The NEN and NRM pins are the input pins
for the mode selection (see Figure 4).
By setting the TxD input pin to logical “low” the transmitter of the TLE7250 drives a “dominant” signal to the CANH
and CANL pins. Setting TxD input to logical “high” turns off the transmitter and the output voltage on CANH and
CANL discharges towards the “recessive” level. The “recessive” output voltage is provided by the bus-biasing (see
Figure 1). The output of the transmitter is considered to be “dominant”, when the voltage difference between
CANH and CANL is at least higher than 1.5 V (V_Diff = V_CANH - V_CANL).
Parallel to the transmitter the normal-mode receiver monitors the signal on the CANH and CANL pins and indicates
it on the RxD output pin. A “dominant” signal on the CANH and CANL pins sets the RxD output pin to logical “low”,
vice versa a “recessive” signal sets the RxD output to logical “high”. The normal-mode receiver considers a voltage
difference (V_Diff) between CANH and CANL above 0.9 V as “dominant” and below 0.5 V as “recessive”.
To be conform with HS CAN features, like the bit to bit arbitration, the signal on the RxD output has to follow the
signal on the TxD input within a defined loop delay t_Loop ≤ 255 ns.
Data Sheet
9
Rev. 1.0, 2015-08-12