Optimal solution for rugged CAN, CAN FD and DeviceNet

In practice, ground potentials vary widely from CAN node to node, which can result in an interruption of communications or destruction of a transceiver. The LTM2889 separates grounds by using inductively coupled CAN transceiver.

LTM2889 provides 2,500VRMS of galvanic isolation, ±60V fault protection on CAN bus interface pins with respect to GND2, greater than 30kV/µs common mode transient immunity, and ±25kV HBM ESD protection. In addition, the device features an extended ±36V common mode range to enable operation in environments with high common mode voltages created by electrical noise or ground potential differences between nodes on the isolated side of the CAN bus.

CAN FD standards overcomes 1 Mbit/s transfer data rate and 8 byte payload (data field) limit of CAN standard. Transfer data rate can be increased up to 2Mbit/s for normal operation and 5Mbit/s for point to point and payload to 64 byte. The LTM2889 operates at data rates between 22kbps and 4Mbps, with an adjustable slew rate to reduce EMI at lower data rates.

The LTM2889 features an integrated, low EMI, DC/DC converter that powers the isolated transceiver and provides up to 0.75W of isolated power for CAN node components. Transition to shutdown mode brings pins connected to CAN bus and RX output to high impedance state and current consumption drops to less than 1µA. During transition to normal mode pins stay in high impedance state until DC/DC converter output voltage reaches predefined threshold. Such a behavior ensures that no glitches appear on CAN bus.

The LTM2889 requires no external components and it is available in commercial, industrial and automotive temperature grades and is available in 15mm x 11.25mm x 3.42mm BGA package.

For more information, please see LTM2889 documentation. For further information about Linear Technology products, please look at our Linear Technology web pages or contact us at sales@soselectronic.com.