TLE6258 Datasheet, PDF (4/13 Pages) Infineon Technologies AG – Single-Wire-Transceiver

Preliminary Data TLE 6258
1.5 Application Information
Start Up
Power Up
Normal Mode
ENN
Vcc
low
ON
ENN high
ENN low
Stand-By ¹⁾
ENN
V_CC
high
ON
1) _{RxD becomes low when wake-up via bus}
Figure 3: State Diagram
For fail safe reasons the TLE6258 has already a pull up resistor of 30kΩ implemented.
To achieve the required timings for the dominant to recessive transition of the bus signal
an additional external termination resistor of 1kΩ is required. It is recommended to place
this resistor in the master node. To avoid reverse currents from the bus line into the
battery supply line in case of an unpowered node, it is recommended to place a diode in
series to the external pull up. For small systems (low bus capacitance) the EMC
performance of the system is supported by an additional capacitor of at least 1nF in the
master node (see figure 6, application circuit).
In order to reduce the current consumption the TLE 6258 offers a stand-by mode. This
mode is selected by switching the Enable Not (ENN) input high (see figure 3, state
diagram). In the stand-by mode a wake-up caused by a message on the bus is indicated
by setting the RxD output low. When entering the normal mode this wake-up flag is reset
and the RxD output is released to transmit the bus data.
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version: 2.02 date: 2001-08-08