TH8062 Datasheet, PDF (18/38 Pages) Melexis Microelectronic Systems – Voltage Regulator with LIN Transceiver

TH8062
Voltage Regulator with LIN Transceiver
Slew Modes and Data rates
The TH8062 is a constant slew rate transceiver which means that the bus driver works with a mode
depended slew rate. In normal mode the slew rate is typical 1.6 V/µs (max. baudrate 20kbit/s) and in low
slew mode typical 0.8 V/µs. The lower slew rate in low slew mode associated with a baud rate of 10.4kbit/s
improves the EME behaviour.
The LIN transceiver of TH8062 is compatible to the physical layer specification according to LIN 2.0
specification for data rates up to 20kbit/s and the SAE specification J2602 for data rates up to 10.4kbit/s.
The constant slew rate principle is very robust against voltage drops and can operate with RC- oscillator
systems with a clock tolerance up to ±2% between 2 nodes.
Low Slew Mode
In this mode the slew rate is switched from the normal value of typ. 1.6V/µs to a low value of typ. 0.8V/µs.
This mode is optimized to send with a maximum baud rate of 10.4kbit/s (acc. to SAE J2602). Because of this
reduction of the slew rate the EME behaviour is improved especially in the frequency range of 100 kHz to
10MHz.
Input TxD
The 5V input TxD controls directly the BUS level:
TxD = low
->
TxD = high ->
BUS = low (dominant level)
BUS = high (recessive level)
The TxD pin has an internal pull up resistor connected to VCC. This guarantees that an open TxD pin
generates a recessive BUS level.
MCU
VCC
I_{PU_TXD}
VCC
R_{PU_TXD}
TxD
Typ.
15k
RC-Filter
(10ns)
TH8062
Figure 8 - TxD input circuitry
TH8062 – Datasheet
3901008062
Page 18 of 38
March 2006
Rev 002