Texas Instruments TPS65994 EVM, Руководство пользователя, Страница: 19 / 59

8 Debugging the EVM
This section discusses various debugging examples. Testing and debugging approaches on the EVM can be
applied to an actual system to help identify any issues.
8.1 Connection Not Established
The following checks help resolve issues when connecting the EVM to another EVM or USB Type-C device and
no status LEDs are on:
• Verify that a firmware image is loaded in on the TPS65994 using the TPS65994 Configuration Tool
• Verify the CC lines are toggling for Dual-Role Port functionality
• Verify the following system supplies:
– System_3V3 and VIN_3V3: 3.3 V
– System_5V : 5 V
– Barrel jack and SYS_PWR: 20 V
– LDO_3V3: 3.3 V
• Verify that the devices connected are compatible. The following are some of the compatible connections:
– Dual-Role Port → UFP
– Dual-Role Port → DFP
– DFP → UFP
• Verify that VBUS is reaching 5 V when connected
8.2 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.
• 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 or PP_EXT switch is closed and is
then opened, once an overcurrent condition is detected.
www.ti.com Debugging the EVM
SLVUBM1C – JANUARY 2019 – REVISED JANUARY 2021
Submit Document Feedback
TPS65994 EVM User Guide 19
Copyright © 2021 Texas Instruments Incorporated