TLE6285 Datasheet, PDF (7/23 Pages) Infineon Technologies AG – LIN-Transceiver LDO

Target Data TLE 6285
In case the voltage regulator control input is not connected to INH output or the
microcontroller is active respectively, the TLE6285 can be set in normal operation mode
without a wake-up via the communication bus.
2.2 LIN Transceiver
The LIN Transceiver has already a pull up resistor of 30kW as termination implemented.
There is also a diode in this path, to protect the circuit from feedback of voltages from
the bus line to the power supply. To configure the TLE 6285 as a master node, an
additional external termination resistor of 1kW is required. To avoid reverse currents from
the bus line into the battery supply line in case of an unpowered node, it is also
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).
An capacitor of 10µF at the supply voltage input V_S buffers the input voltage. In
combination with the required reverse polarity diode this prevents the device from
detecting power down conditions in case of negative transients on the supply line.
2.3 Input Capacitor
The input capacitor C_I is necessary for compensation of line influences. Using a resistor
of approx. 1 W in series with C_I, the oscillating circuit consisting of input inductivity and
input capacitance can be damped. The output capacitor is necessary for the stability of
the regulating circuit. Stability is guaranteed at values ³ 22 mF and an ESR of £ 5 W
within the operating temperature range. For small tolerances of the reset delay the
spread of the capacitance of the delay capacitor and its temperature coefficient should
be noted.
2.4 Voltage regulator
The 6285 incorporates a PNP based very low drop linear voltage regular. It regulates the
output voltage to V_CC = 5 V for an input voltage range of 5.5 V £ V_I £ 45 V. The control
circuit protects the device against potential caused by damages overcurrent and
overtemperature.
The internal control circuit achieves a 5 V output voltage with a tolerance of ± 2% in the
temperature range of T_j = – 40 to 150 °C.
The device includes a power on reset and an under voltage reset function with adjustable
reset delay time and adjustable reset switching threshold as well as a sense control/early
warning function. The device includes an inhibit function to disable it when the ECU is
not used for example while the motor is off.
The reset logic compares the output voltage V_CC to an internal threshold. If the output
voltage drops below this level, the external reset delay capacitor C_D is discharged. When
V_D is lower than V_LD, the reset output RO is switched Low. If the output voltage drop is
Version 1.02
7
2002-05-15