7.2.2 Resetting Behavior
Improper configurations and shorts can cause a USB Type-C PD system to constantly reset. The following
checks should be used to debug these types of issues:
• Verify that the essential power paths have the correct voltages:
– System_3V3 and System_5V
– System Power: 20 V (or the appropriate configured voltage)
• Probe VBUS, CC1, and CC2 to check for any anomalies.
shows a successful power contract.
• When there is a short on VBUS, the initial 5 V on VBUS is not present
• Check for a small spike on VBUS during a plug event to verify that the PP_HV or PP_EXT switch is closed
and is then opened, once an overcurrent condition is detected.
Figure 7-5. USB Type-C
™
Connection and PD Negotiation
Connecting the EVM
36
TPS65988 Evaluation Module
SLVUB62B – JUNE 2017 – REVISED NOVEMBER 2020
Copyright © 2020 Texas Instruments Incorporated
