SLYT834 March   2023 ISOUSB211

 

  1. 1 Introduction
  2. 2 Existing implementation of OTG USB applications
  3. 3  On-the-go operation
  4. 4 Implementation of isolated OTG
  5. 5 Demonstration of OTG with ISOUSB211 EVM
  6. 6 Scenario A: Isolated OTG module connected to a USB-drive (bus-powered)
  7. 7  Scenario B: Isolated OTG module connected to a laptop (host)
  8. 8 Demonstration
  9. 9 Connect phone to laptop
  10. 10Connect phone to USB-drive
  11. 11Summary

10 Connect phone to USB-drive

In #FIG_LQB_PM1_MVB, an OTG capable phone (with a female micro-B connector, dual role port) is connected to a flash-drive (with a type-A port) through a type-A female to micro-A male connector (use a type-A male to type-A male connector to connect to EVM). The experiment is for copying the files from the flash-drive to phone.

Figure 10-1 ISOUSB211+Pendrive (OTG Module) connected to a Host.

During the connect, the cable end connected to phone has ID pin shorted to ground (A-type device). The phone recognizes the ID pin set to low, it assumes the A-type role. The reverse power path established from the SN6505 is active, and powers up the flash-drive. The flash-drive asserts a pull up on DP line (indicating the B-type role) and ISOUSB211 introduces its internal 1.5kΩ pull-up on side 2. After this, the communication between the A-type and B-type device happens as per the USB2.0 standard.

The peripheral is able to communicate and data transfer was successful.