SNLS638A December 2018 – August 2019 DP83825I
The DP83825 uses many of the functional pins as strap options to place the device into specific modes of operation. The values of these pins are sampled at power up or hard reset. During software resets, the strap options are internally reloaded from the values sampled at power up or hard reset. The strap option pin assignments are defined below. Configuration of the device may be done through the strap pins or through the management register interface. A pullup resistor or a pulldown resistor of suggested values may be used to set the voltage ratio of the strap pin input and the supply to select one of the possible selected modes. The MAC interface pins must support I/O voltages of 3.3 V and 1.8 V. As the strap inputs are implemented on these pins, the straps must also support operation at 3.3-V and 1.8-V supplies depending on what voltage was selected for I/O. All strap pins have two levels.
|MODE||TARGET VOLTAGE||IDEAL RESISTORS|
|Vmin (V)||Vtyp (V)||Vmax (V)||Rhi (kΩ)||Rlo (kΩ)|
|0||0||0.35 x VDDIO||OPEN||2.49|
|1||0.7 x VDDIO||VDDIO||2.49||OPEN|