General description
The TJA1081B is a FlexRay node transceiver that is fully compliant with the FlexRay
electrical physical layer specification V3.0.1 (see Ref. 1). In order to meet the
JASPAR-specific requirements, it implements the ‘Bus driver increased voltage amplitude
transmitter’ functional class. It is primarily intended for communication systems from
2.5 Mbit/s to 10 Mbit/s and provides an advanced interface between the protocol
controller and the physical bus in a FlexRay network.
The TJA1081B features enhanced low-power modes, optimized for ECUs that are
permanently connected to the battery.
The TJA1081B provides differential transmit capability to the network and differential
receive capability to the FlexRay controller. It offers excellent EMC performance as well as
effective ESD protection.
The TJA1081B actively monitors system performance using dedicated error and status
information (that can be read by any microcontroller), along with internal voltage and
temperature monitoring.
The TJA1081B supports mode control as used in the TJA1080A (see Ref. 3) and is fully
function and footprint compatible with the TJA1081 (see Ref. 2).

Features and benefits
Optimized for time triggered communication systems
 Compliant with FlexRay electrical physical layer specification V3.0.1 (see Ref. 1)
 Meets JASPAR requirementsasdescribedinthe ‘Busdriverincreasedvoltage
amplitudetransmitter’functionalclass
 Automotive product qualification in accordance with AEC-Q100
 Data transfer rates from 2.5 Mbit/s to 10 Mbit/s
 Supports 60 ns minimum bit time at 400 mV differential input voltage
 Very low ElectroMagnetic Emissions (EME) to support unshielded cable, meeting
latest industry standards
 Differential receiver with wide common-mode range for high ElectroMagnetic Immunity
(EMI), meeting latest industry standards
 Auto I/O level adaptation to host controller supply voltage VIO
 Can be used in 14 V, 24 V and 48 V powered systems
 Instant transmitter shut-down interface (via BGE pin)
 Independent power supply ramp-up for VBAT, VCC and VIO3

Low-power management
 Low-power management including inhibit switch
 Very low current in Sleep and Standby modes
 VBAT operating range: 4.75 V to 60 V
 Gap-free specification
 Local and remote wake-up
 Supports remote wake-up via dedicated data frames
 Wake-up source recognition

Diagnosis (detection and signaling)
 Enhanced supply monitoring of VBAT, VCC and VIO
 Overtemperature detection
 Short-circuit detection on bus lines
 VBAT power-on flag (first battery connection and cold start)
 Clamping diagnosis on pin TXEN
 BGE status feedback

Protection
 Bus pins protected against 6 kV ESD pulses according to IEC61000-4-2 and HBM
 Pins VBAT and WAKE protected against 6 kV ESD pulses according to IEC61000-4-2
 Bus pins protected against transients in automotive environment (according to
ISO 7637 class C)
 Bus pins short-circuit proof to battery voltage (14 V, 24 V and 48 V) and ground
 Fail-silent behavior in the event of an undervoltage on pins VBAT, VCC or VIO
 Passive behavior of bus lines while the transceiver is not powered
 No reverse currents from the digital input pins to VIO or VCC when the transceiver is not powered

Functional classes according to FlexRay electrical physical layer
specification (see Ref. 1)
 Bus driver voltage regulator control
 Bus driver - bus guardian interface
 Bus driver logic level adaptation
 Bus driver remote wake-up
 Bus driver increased voltage amplitude transmitter (JASPAR)