TCAN1042V-Q1: question about RXD pin of TCAN1042VDRQ1

Dear TI team

Is it a component defect?

Hi User,

Is the state of the TXD pin steady during the transition? If the TXD pin is driven low, this can cause the RXD pin to also be low, even when nothing else is connected to the CAN bus. If possible, please capture and share waveforms of the STB, RXD, CANH, and CANL signals during this transition. 

Can you also share the lot trace code of the device showing this behavior? This should be included on the shipping label. If this is not available, please share the top-side markings of the device. 

Let me know if you have any other questions in the meantime. 

Regards,
Eric Schott

Dear TI friends

 Here is the chip top side markings.

The state of the TXD pin keep high level during the transition.

The waveforms will be uploaded by monday.

Thanks

Hi User,

I'm having trouble identifying this lot based on the code shown here. I'll continue to check to see if I missed something. In the meantime, is it possible to share the full lot code and date from the shipping label?

Please also share waveforms once they are available.

Regards,
Eric Schott

Dear  TI friends

I am sorry that i can't find its shipping label or lot code.

Here is the waveforms about CANRX CANTX CANH CANL and CANSTANDBY.

I keep  CANH CANL CANRX and CANTX pin float in order to minize external interference when I test the waveforms.

The 3.3V VIO and 5V VCC is always on.

• The waveform of CANTX is as follows.As we can see,the CANTX pin is always high.

• We don't have a five channel scope,so i can't test CANTX CANRX CANH CANL CANSTANDBY simultaneously.

Hi,

Thanks for your patience on this. I'm working with some of our engineers internally to diagnose this behavior. 

So that we may recommend the best action for you, can you let us know a bit about how this behavior impacts your system? Does the pulse on RXD during wake-up cause any errors or unwanted interrupts? If so, is it possible to ignore this behavior with software, or would a hardware solution to filter this pulse be preferable? 

I'll be in touch with more information once I have it available. 

Regards,
Eric Schott

Dear TI friends

The CANRXD pin connects the input of a trigger.

The abnormal negative pulse leads to unwanted interrupts,which cause the accidental wake-up events.

It may be ingored by software.

Could you share more information if it is a component defect ?

Thanks.