• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 100 subscribers
  • Views 211 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AM4378: EVM USB0 connections

Shine
Genius 13655 points
Part Number: AM4378

Hello Champs,

The GP EVM and StarterKit schematic are different when using USB0 in DRD mode. 

In Starterkit board, the USB0_ID is connected to NMOS Q9 which connected to GPMC_WAIT0. While in GP EVM schematic, the USB0_ID is not brought out, the VUSB_VBUS0 is connected to NMOS Q2 instead, the NMOS Q2 is connected to GPIO_13. 

Which one is correct? What the function of NMOS?

Below are the GP EVM and StarterKit schematic.


StarterKit schematic

GP EVM schematic



Thanks.
Best Regards
Shine

  • 0
    TI__Mastermind 27720 points

    Hello Shine,

    1) DRD requires that the ID pin be connected directly to the ID pin of the USB Micro-AB connector. If the port is Device Mode only, the ID pin should be left floating. If the port is Host-only mode, the ID pin should be grounded and the USB Type A connector should be used. The ID pin should never be connected to a voltage source.

    2) The NMOS is not a requirement. It is was put there for internal testing.