TJA1145A Power Sequence Issue

[lmb_bruker]

Hello,

I am experiencing an issue when debugging a board using the TJA1145AT. Normal operation brings on VBAT before VCC or VIO, but I found when using a debugger for the microprocessor, VIO was powered via the debugger without VBAT and VCC powered. After this happens, the board stops working, and it seems like the TJA1145AT is damaged. I can still talk to the microprocessor via debugger (successful programming and reading out memories).

Is it possible to damage the TJA1145AT if VIO is powered without VBAT and VCC?

[guoweisun]

I don't think it will damage if VIO powered without Vbat and Vcc, but you need pay attention on the limited value once above this max 6V it will damage:

guoweisun_0-1695340949113.png