SN65HVD232: ic burns,schematic review,

Kalisankar,

In addition to Clemens comments, because I agree there should be some protection on the CAN bus, is there anything in particular happening in the application when this damage occurs?

Regards,

Eric Hackett

Hi Eric,

            While connecting to the bus, the IC burns and 3.3V and GND lines gets short. once i remove the IC everything works fine.

Kalisankar,

Can you give more details of the application? The CAN IC should not be immediately burning up when it is connected to the bus. It sounds like there is damage occurring to the CANH and/or CANL pins immediately which shorts 3.3V supply pull-up on CANH to the ground connection on CANL. 

Regards,

Eric Hackett

Hi Eric,

            The application is to monitor the battery and load parameters. The battery BMS and load has termination resistors so i did not add and resistors in CANH and CANL lines. and also there is no Pull-up or Pull down resistors in CAN lines. When i hot plug my devce in the bus between battery and load some times the can IC fails in my circuit only. 

Hi Clemens,

               Thanks for you advice. Here with i have attached modified PCB layout. Please check and let me know. 

Kalisankar,

Have you looked at the signal on CANH and CANL upon insertion/connection? If the different nodes of your device have different ground potential levels, then it could possibly cause a severe voltage differential during connection.

Also, do you know the effective termination strength of the BMS?

Best,

Danny