TCAN1042-Q1: Device State/Behavior vs Vcc

Hello Yokota-san,

thank you for your question and the graph; only one note, the absolute maximum value for the VCC is 7V while the minimum is -0.3V.

Now if I understand correctly, you are trying to maintain the UVcc above threshold  while working with a VCC which is outside the recommended boundaries.

In this case I would think of the device still functioning and able to send and receive data but its specifications will probably be outside the typical/nominal values that are presented in the datasheet. That is, electrical characteristics such as High or low level input voltages, High or low level output voltages, all the parameters related to the Driver and the Receiver will most likely be out of the specified values. Because of these values being out of range, also the switching characteristics will be out of the specified values; having lower voltages and currents will cause slower or higher propagation delays.

Just as a reminder, this device as you know has an undervoltage detection on the supply terminals.

If VCC > UVcc , the device is normally working with its Bus Output mirroring the TXD while the RXD mirrors the bus state (low if CAN dominant, high if CAN recessive).

If VCC < UVcc , the device enters a protected mode with both Bus Output and RXD showing High Impredance.

Let me know if you have a specific working point or need.

Best regards,

Adrian