Mini High-Speed CAN Companion System Basis Chip

The UJA1169L mini high-speed CAN companion System Basis Chip (SBC) belongs to the UJA1169 product series and can be used as a companion chip in applications where a second SBC is dedicated to the application microcontroller. It contains an ISO 11898-2:201x (upcoming merged ISO 11898-2/5/6) compliant HS-CAN transceiver and an integrated 5 V 250 mA scalable supply (V1) for additional transceivers and/or other loads. It also features a watchdog and a Serial Peripheral Interface (SPI). The UJA1169L companion SBC can be operated in very low-current Standby and Sleep modes with bus and local wake-up capability.

The UJA1169L is designed to be used in applications that require more than one transceiver or additional power supply resources. Using a standard device as the secondary SBC in an application can be problematic. The secondary SBC will have a different interface supply domain to the main SBC, creating a high risk of reverse supply currents. The UJA1169L resolves this issue by providing a dedicated VIO input pin that allows it to adapt to any other supply domain.

Incorporating the UJA1169L companion SBC in an application allows it to be easily scaled or extended by adding, for example, an additional 5 V power supply, CAN transceiver, off-board 5 V sensor supply or even a secondary independent watchdog function with independent LIMP output for special ASIL-related applications.

The UJA1169L comes in four variants. The UJA1169LTK and UJA1169LTK/F feature a second onboard 5 V regulator (V2) that supplies the internal CAN transceiver and can also be used to supply additional onboard hardware.

The UJA1169LTK/X and UJA1169LTK/X/F are equipped with a 5 V supply (VEXT) for off-board components. VEXT is short-circuit proof to the battery, ground and negative voltages. The integrated CAN transceiver is supplied internally via V1.

The UJA1169LTK/F and UJA1169LTK/X/F variants support ISO 11898-6:2013 and ISO 11898-2:201x compliant CAN partial networking with a selective wake-up function incorporating CAN FD-passive. CAN FD-passive is a feature that allows CAN FD bus traffic to be ignored in Sleep/Standby mode. CAN FD-passive partial networking is a good fit for networks that support both CAN FD and classic CAN communications. It allows normal CAN controllers that do not need to communicate CAN FD messages to remain in partial networking Sleep/Standby mode during CAN FD communication without generating bus errors.

The UJA1169L implements the standard CAN physical layer as defined in the current ISO11898 standard (-2:2003, -5:2007, -6:2013). Pending the release of the upcoming version of ISO11898-2:201x including CAN FD, additional timing parameters defining loop delay symmetry are included. This implementation enables reliable communication in the CAN FD fast phase at data rates up to 2 Mbit/s.

A dedicated LIMP output pin is provided to flag system failures.

A number of configuration settings are stored in non-volatile memory. This arrangement makes it possible to configure the power-on and limp-home behavior of the UJA1169L to meet the requirements of different applications.