The DP83TC812 offers sensors for monitoringvoltage at the supply pins. Undervoltage monitoring are always active in the DP83TC812 by default. If an undervoltage condition is detected, interrupt status flag is set in register 0x0013. These interrupts can also be optionally routed to the INT pin using the same register.

The following method must be used to read each sensor.

• Step 1: Program register 0x0467 = 0x6004 ; Initial configuration of monitors
• Step 2: Program register 0x046A = 0x00A3; Enable Monitors
• Step 3: Configure register 0x0468 with the corresponding setting to select the required sensor.
  • VDDA Sensor: Use 0x0468 = 0x0920
  • VSLEEP Sensor: Use 0x0468 = 0x1920
  • VDDMAC Sensor: Use 0x0468 = 0x2920
  • VDDIO Sensor: Use 0x0468 = 0x3920
• Step 4: Read register 0x047B[14:7] and convert this output code to decimal.
• Step 5: Use the output code in the following equations to get the sensor's absolute value. Refer to Table 7-2 table for constant values for corresponding sensors.
  • vdda_value = 3.3 + (vdda_output_code - vdda_output_mean_code)*slope_vdda_sensor
  • vsleep_value = 3.3 + (vsleep_output_code - vsleep_output_mean_code)*slope_vsleep_sensor
  • vddmac_value = 3.3 + (vddmac_output_code - vddmac_output_mean_code)*slope_vddmac_sensor
  • vddio_value = 3.3 + (vddio_output_code - vddio_output_mean_code)*slope_vddio_sensor