UJA1166ATK wake up problem

[gkhan123]

Hi,

I use UJA1166ATK sbc with mcu S32K118. VIO pin connect with V1(5VDC). Not externally supply.

On power up, UJA1166ATK is in sleep mode because VIO is under the threshold voltage value.

I try to do local wake up from WAKE pin. I apply a high to low signal to "wake" pin. UJA1166ATK is still in sleep mode.

If I try to apply a remote wake up from canbus, i don't know uja1166a work in normal or standby mode and produce V1. I don't know my design is correct or not. 

Should I supply VIO externally ? 

For solve this problem, 

Should I apply a remote wake up from canbus ?

Should I supply VIO externally ?

Should I change the UJA1166ATK with UJA1163ATK ? (uja1163 doesn't have a VIO pin.)

Thanks.

[gkhan123]

Hi,

thanks for answer.

I'm sure that INH pin is float state and temperature protection is inactive.

In my design, SLPN pull up and VIO is connected with V1. There is no externally supply. So, I'm not sure the SLPN pin is high all the time or not.

I will observe the SLPN pin, but i have a suspicion that i have a design mistake for VIO and SLPN connections. I guess V1 is inactive in standby mode.

[diazmarin09]

Hello,

Thank you for using the NXP community.

So, your device is in SLEEP mode based on the INH pin.

Please note that, in order to go from SLEEP to STANDBY mode and then NORMAL mode, the SLPN pin must be HIGH (provided VIO > Vuvd(VIO)).

I do recommend using the UJA1166A-EVB as a reference for your design.

Please let me know if this information is useful for you.

Regards,

David

[diazmarin09]

Hello,

I hope all is great with you. Thank you for using the NXP communities.

You are correct, wake-up can be triggered remotely via a standard wake-up pattern on the CAN bus or locally via the WAKE pin.

1. Could you please confirm that the INH pin is floating? In Sleep mode, the transceiver behaves like in Standby Mode with the exception that pin INH is set floating and temperature protection is inactive.

2. A HIGH level on SLPN (provided a valid voltage is present on VIO), a local wake-up via the WAKE pin or a remote CAN bus wake-up will cause the UJA1166A to wake up from Sleep mode and switch to Standby mode. Is the SLPN pin HIGH all the time?

I hope this information helps.

Regards,

David