ZHCSMV3A December 2020 – December 2021 TPS552882-Q1
PRODUCTION DATA
The TPS55288 outputs a voltage at the CDC pin proportional to the sensed voltage across a output current sensing resistor between the ISP pin and the ISN pin. Equation 7 shows the exact voltage at the CDC pin related to the sensed output current.
To compensate the voltage drop across a cable from the terminal of the USB port to its powered device, the TPS552882-Q1 can lift its output voltage in proportion to the load current by placing a resistor between the CDC pin and AGND pin.
When using external output voltage feedback on the TPS552882-Q1, the output voltage rises in proportional to the current sourcing from the CDC pin through the resistor at the CDC pin. It is recommended to use 100-kΩ resistance for the up resistor of the resistor divider. Equation 8 shows the output voltage rise versus the sensed output current, resistance at the CDC pin and the up resistor of the output voltage feedback resistor divider.
where
When RFB_UP is 100 kΩ, the output voltage rise versus the sensed output current and the resistor at the CDC pin is shown in Figure 7-6