描述 Description

The SN65HVD251 is intended for use in applications employing the Controller Area Network (CAN) serial communication physical layer in accordance with the ISO 11898 Standard. The SN65HVD251 provides differential transmit capability to the bus and differential receive capability to a CAN controller at speeds up to 1 megabit per second (Mbps).
Designed for operation in harsh environments, the device features crosswire, overvoltage, and loss of ground protection to ±36 V. Also featured are overtemperature protection as well as -7-V to 12-V common-mode range, and tolerance to transients of ±200 V. The transceiver interfaces the single-ended CAN controller with the differential CAN bus found in industrial, building automation, and automotive applications.
Rs, pin 8, selects one of three different modes of operation: high-speed, slope control, or low-power mode. The high-speed mode of operation is selected by connecting pin 8 to ground, allowing the transmitter output transistors to switch as fast as possible with no limitation on the rise and fall slope. The rise and fall slope can be adjusted by connecting a resistor to ground at pin 8; the slope is proportional to the pin's output current. Slope control with an external resistor value of 10 k gives ~2 V/μs slew rate.
If a high logic level is applied to the Rs pin 8, the device enters a low-current standby mode where the driver is switched off and the receiver remains active. The local protocol controller returns the device to the normal mode when it transmits to the bus.

特性 Features

? Qualified for Automotive Applications
? Drop-In Improved Replacement for the PCA82C250 and PCA82C251
? Bus-Fault Protection of±36 V
? Meets or Exceeds ISO 11898
? Signaling Rates
up to 1 Mbps
? High Input Impedance Allows up to 120 SN65HVD251 Nodes on a Bus
? Bus Pins ESD Protection Exceeds 9 kV (HBM)
? Unpowered Node Does Not Disturb the Bus
? Low-Current Standby Mode: 200 μA Typical
? Thermal Shutdown Protection
? Glitch-Free Power-Up and Power-Down Bus Protection for Hot Plugging
? DeviceNet? Vendor ID #806
? APPLICATIONS
- CAN Data Buses
? Industrial Automation
- DeviceNet Data Buses
? Smart Distributed Systems (SDS?)
? SAE J1939 Standard Data Bus Interface
? NMEA 2000 Standard Data Bus Interface
? ISO 11783 Standard Data Bus Interface

The signaling rate of a line is the number of voltage transitions that are made per second expressed in bps (bits per second).