SN65HVD251DR-HX

SN65HVD251DR-HX is an interface IC between the CAN protocol controller and the physical bus, designed primarily for high-speed applications in passenger vehicles, with a maximum speed of 1 MBit/s. It supports differential transmission to the bus and differential reception from the CAN controller. The device is fully compliant with ISO 11898, with a data transfer rate of 1 Mbps, enabling differential signal transmission between the bus and the CAN protocol controller in trucks, buses, automobiles, industrial control, and other applications. The driver stage integrates current-limiting protection to prevent circuit damage due to short circuits to positive or negative supply voltages. The D pin has a built-in pull-up connection to VCC, ensuring the bus remains in a recessive state when the D pin is unpowered. The Rs pin has a direct pull-up connection to VCC, ensuring the transceiver remains in standby mode when the Rs pin is unpowered. When the supply voltage drops, the D, Rs, and R pins enter an open state to prevent reverse current flow through these pins. The device also features thermal protection: when the junction temperature exceeds 160°C, the driver stage current is reduced to lower power dissipation, allowing the chip to cool down, while the rest of the chip continues to operate normally during this period. In addition, a built-in D dominant timeout timer circuit prevents the bus lines from being driven to a permanent dominant state (blocking all network communication) when the D pin is forced permanently low due to hardware or software faults. This timer is triggered by a falling edge on the D pin; if the low level on the D pin persists beyond the internal timer value, the transmitter is disabled, driving the bus to a recessive state. The control pin Rs allows selection between two operating modes: high-speed mode and standby mode. In high-speed mode (normal mode), with the Rs pin connected to ground, the transceiver transmits and receives data via the CANH and CANL bus lines. In this mode, the differential receiver converts analog data on the bus to digital data and outputs it to the R pin via a multiplexer. If the Rs pin is left floating or connected to a high level, standby mode is entered. In this mode, the transmitter and receiver are disabled, and the bus lines are monitored by a low-power differential comparator. When a high level is applied to the Rs pin, the low-power receiver and wake-up filter are activated. Once the low-power differential comparator detects a bus level above the dominant state threshold tBUS, the R pin goes low.

Applications

• Automotive electronics
• Industrial control automation
• Smart instrumentation
• Building automation systems
• Road traffic control automation

Key features

• Operating voltage range: VCC = 5V ± 10%
• Fully compliant with ISO 11898 standard
• High-speed operation (up to 1 MBaud)
• Transceiver disconnected from bus in unpowered state (zero load)
• Supports connection of at least 110 nodes
• Ultra-low current standby mode with remote wake-up capability via bus
• Differential receiver with high common-mode range for enhanced EMI immunity
• Transmit data dominant timeout function
• Bus pins protected against transient disturbances in automotive environments
• Thermally stable design