ZHCSGV1C June 2017 – March 2018 TPS25740B
PRODUCTION DATA.
The VAUX pin is the output of a linear regulator and the input supply for internal power management circuitry. The VAUX regulator draws power from VDD after establishing a USB PD contract unless it is not available in which case it draws from VPWR. Changes in supply voltages will result in seamless switching between supplies.
If there is a load on the DVDD pin, that current will be drawn from the VPWR pin unless the device has stabilized into a USB PD contract or VPWR is below its UVLO.
Connect VAUX to GND via the recommended bypass capacitor. Do not connect any external load that draws more than I(VAUXEXT). Locate the bypass capacitor close to the pin and provide a low impedance ground connection from the capacitor to the ground plane.
VDD should either be grounded or be fed by a low impedance path and have input bypass capacitance. Locate the bypass capacitors close to the VDD and VPWR pins and provide a low impedance ground connection from the capacitor to the ground plane.