TH8082 Datasheet, PDF (12/26 Pages) List of Unclassifed Manufacturers – Single LIN Bus Transceiver

TH8082
Enhanced SoloLIN Transceiver
3. Functional Description
3.1 Initialization
After power on, the chip enters automatically the V_BAT-standby mode. In this intermediate mode the INH
output will become HIGH (V_S) and therefore the ECU - voltage regulator will provide the V_CC - supply. The
transceiver will remain the V_BAT-standby mode until the controller sets it to normal operation (EN = High).
Only in this mode bus communication is possible. The TH8082 switches itself in the V_BAT-standby mode if
V_CC is missing or below the threshold.
3.2 Operating Modes
Via the EN pin it is possible to switch the TH8082 into different operating modes:
Normal Mode
The whole TH8082 is active. Switching to normal mode can only be done via the EN pin with EN=high.
Sleep Mode
The sleep mode (EN = LOW) can only be reached from normal mode and permits a very low power
consumption because the transceiver and even the external voltage regulator will be disabled. If the V_CC has
been switched off a wake-up request from the bus line (remote wake up) will cause the TH8082 to enter the
V_BAT-standby mode (V_CC is present again) and sets the RxD output to low until the device enters the normal
operation mode (active LOW interrupt at RxD). If the INH pin is not connected to the regulator or the
inhibitable external regulator is not the one that provides the V_CC - supply, the normal mode is directly
accessible by logic high on the EN pin. (wake up via mode change/local wake up)
In order to prevent an unintended wake-up caused by disturbances of the automotive environment incoming
dominant signals from the bus have to exceed the wake-up delay time.
Thermal Shutdown Mode
If the junction temperature T_J is higher than 155°C, the TH8082 will be switched into the thermal shutdown
mode. Within this mode the transmitter will be switched off.
If T_J falls below the thermal shutdown temperature (typ. 140°C) the TH8082 will be switched to the previous
state.
3.3 Mode control
EN
VCC
0
0
0
1
1
1
0
0
0
1
0
0/1
Comment
VBAT-standby , power on
VBAT-standby , VCC on
Normal mode
Sleep mode
Sleep mode
regulator not disabled
directly switch to normal mode with EN = 1
Remote wake up request
Table 1 - Mode control
INH
Vs
Vs
Vs
floating
RxD
0
X
Vcc = recessive
0 = dominant
0
floating
Vcc
Vs
0 - Active low wake up
interrupt
TH8082 – Datasheet
3901008082
Page 12 of 26
Feb 2007
Rev 007