TCAN1043A-Q1: Wake Up Transition

Hi Rakesh,

Wake via the CAN bus is done by the reception of a wake up pattern (WUP). This is a filtered condition that is meant to ignore noise on the bus but be responsive to a wake signal that will be sent by a remote node. The WUP is defined so that any valid CAN frame will be recognized as a valid wake condition. Therefore there is no special consideration needed when sending a WUP to wake a transceiver - bus activity CAN simply be initiated and the CAN traffic will wake all WUP-sensitive devices. 

Let me know if you have any more questions. 

Regards, 
Eric Schott 

I am sorry i didnt mention, I asked you about the Hardware wake and not the CAN Wake Up 

Hi Rakesh,

The WAKE pin is a battery-level input pin that can be used to wake the device by either a high-to-low or low-to-high edge on the pin. This is needed because it is common for Vcc and Vio to be unpowered during sleep mode to save power, so the Vsup supply needs to be referenced. The transition on the pin can be created by a switch such as an ignition switch or by a FET if the WAKE signal is to be controlled by a lower voltage signal. 

Let me know if this is clear or if there is anything else about this feature that you would like to know. 

Regards, 
Eric Schott 

Right now for our purpose we connected Wake up as a low side with the switch, So as afail condition if the switch is stuck and released will the device identify this as low to hig transition ?

Sorry If this is confusing,

I will explain The HIgh to Low or Low to High Trasistion for wake up How exactly the Device(1043) Identfies the Transition?

SO as it should wake up fro High to Low or from Low to High