深圳市尚想信息技术有限公司

Features 3 Description
The HVD251 is intended for use in applications 1• Drop-In Improved Replacement for the
employing the Controller Area Network (CAN) serial PCA82C250 and PCA82C251 communication physical layer in accordance with the
• Bus-Fault Protection of ±36 V ISO 11898 Standard. The HVD251 provides
• Meets or Exceeds ISO 11898 differential transmit capability to the bus and
differential receive capability to a CAN controller at • Signaling Rates(1) up to 1 Mbps
speeds up to 1 megabits per second (Mbps).
• High Input Impedance Allows up to 120 Nodes on
a Bus Designed for operation in harsh environments, the
device features cross-wire, overvoltage and loss of • Bus Pin ESD Protection Exceeds 14 kV HBM ground protection to ±36 V. Also featured are
• Unpowered Node Does Not Disturb the Bus overtemperature protection as well as –7-V to 12-V
• Low-Current Standby Mode: 200-μA Typical common-mode range, and tolerance to transients of
• Thermal Shutdown Protection ±200 V. The transceiver interfaces the single-ended
CAN controller with the differential CAN bus found in
• Glitch-Free Power-Up and Power-Down CAN Bus industrial, building automation, and automotive Protection for Hot-Plugging applications.
• DeviceNet Vendor ID #806 Rs, pin 8, selects one of three different modes of
(1) The signaling rate of a line is the number of voltage operation: high-speed, slope control, or low-power
transitions that are made per second expressed in bps (bits mode. The high-speed mode of operation is selected per second). by connecting pin 8 to ground, allowing the
transmitter output transistors to switch as fast as 2 Applications possible with no limitation on the rise and fall slope.
• CAN Data Buses The rise and fall slope can be adjusted by connecting
a resistor to ground at pin 8; the slope is proportional • Industrial Automation
to the pin's output current. Slope control with an
• SAE J1939 Standard Data Bus Interface external resistor value of 10 kΩ gives about 15-V / μs
• NMEA 2000 Standard Data Bus Interface slew rate; 100 kΩ gives about 2-V/μs slew rate.
If a high logic level is applied to the Rs pin 8, the Block Diagram 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.