If UVSUP decreases to trip point, the device is in standby mode. A UVSUP event causes the INH pin to turn off. When the VSUP is greater than UVSUP and INH turns on the SWE timer will start. If VSUP decreases more, the TCAN114x-Q1 shuts everything down as the POR level has been reach and when VSUP returns, the device comes up as if it is the initial power on. All registers are cleared and the device has to be reconfigured. If an under voltage event takes place on the VCC pin, the device starts tUVSLP timer to determine if this is a real event. If after the timer times out, the device enters fail-safe or sleep mode depending upon device set up. See Figure 10-23. The TCAN114x-Q1 also provides voltage over protection on the VCC input. Once detected, the device enters fail-safe or sleep mode depending upon device set up. See Table 10-8 for the relationship between VSUP and VCC.
|> UVSUP||> UVCC||Normal||Per TXD||Mirrors Bus|
|> UVSUP||< UVCC||Fail-safe or Sleep||High Impedance||High (Recessive)|
|< UVSUP||NA||Power off||High Impedance||High Impedance|