4.1.1.1 Power-On Reset (POR)

A Power-On Reset occurs when power is initially applied to the device, or if any power supply drops below a falling threshold. The device will remain in reset until all power supplies have passed the appropriate rising threshold, and the LAN8650/1 is fully operational. The IRQ_N pin will be asserted and the RESETC (Reset Completed) bit of the OA_STATUS0 Register will be set to 1, as specified by the Open Alliance. This indicates to the station controller that the device has been reset and requires configuration. The rising and falling thresholds are listed below in Table 4-1.

For more information about waking from low-power sleep mode, see the Sleep Mode Section of this document.

Table 4-1. POR Supply Thresholds
SupplyRising Threshold1Falling Threshold1
VDDAU2.5V2.3V
VDDA2.5V2.3V
VDDP1.9V1.9V
VDDC21.5V1.4V
Note:
  1. Rising and falling threshold voltages are design parameters and are neither tested nor characterized.
  2. The LAN8651 internal 1.8V supply may be monitored externally at the CCOMP pin.