• State
  • Locked Locked
  • Replies 5 replies
  • Subscribers 31 subscribers
  • Views 328 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.

TMDSEMU110-U: TMDSEMU110-U - XDS110 JTAG Debug Probe : Galvanic isolation

Cvetan Marinov1
Prodigy 90 points
Part Number: TMDSEMU110-U
Other Parts Discussed in Thread: TMS320F280049C, , LAUNCHXL-F280049C

Hello Dear All,

For development of HV (400V+) motor controller using TMS320F280049C , it is required to provide a galvanic isolation betweein the JTAG Debug Probe and the PC.

The LAUNCHPAD-LAUNCHXL-F280049C implements on-board the USB digital isolator ADuM3160BRWZ.

What other proven outside-the-board solution would you recommend to solve the situation?

Best regards,

Cvetan Marinov

  • 0
    Guru 92251 points

    BlackHawk have the XDS110 JTAG Isolator. However, that only has Standard 4-wire JTAG support (IEEE 1149.1).

    Whereas the TMS320F280049C can use either 4-wire JTAG or 2-wire cJTAG.

    I.e. if you did use the XDS110 JTAG Isolator would have to use 4-wire JTAG meaning the TDI and TDO pins on the TMS320F280049C can't used for GPIOs.

  • 0
    TI__Mastermind 28275 points

    Hi Cvetan,

    Did Chester's suggestion help resolve your issue? This thread is a bit old but still offers useful recommendations. Let us know if none of these are what you are looking for.

  • 0 in reply to Frank Ankapong
    Prodigy 90 points

    Hi Frank,

    The suggestion of Chester is helpuful, however it costs most than the JTAG Emulator itself and contains only two digital isolator IC's. Are there any considerations to isolate the JTAG signal? My inetntion is to implemeng galvanic barrier on the USB interface not on the JTAG signals. Do you recommend such approach? Indeed the same approach is implemented on the LAUNCHPAD-LAUNCHXL-F280049C and currently I do not see any drawbacks. I just need reliable and working solution. So, could you please reveal any arguments for using the one or for the other approaches?

  • 0 in reply to Chester Gillon
    Prodigy 90 points

    Hello Chester,

    Thank you for the proposal, it is under consideration.

  • 0 in reply to Cvetan Marinov1
    Guru 92251 points
    Cvetan Marinov1 said:
    My inetntion is to implemeng galvanic barrier on the USB interface not on the JTAG signals. Do you recommend such approach?

    I guess the trade off between the approaches is a combination of:

    • The cost
    • The Isolation Voltage
    • If it slows down the speed of debugging

    As for the impact on the speed of debugging when implementing a galvanic barrier on the USB interface:

    1. The USB interface on the TMDSEMU110-U supports USB high-speed (480 Mbits/s)
    2. The LAUNCHXL-F280049C uses the single chip ADuM3160BRWZ "Full/Low Speed 2.5 kV USB Digital Isolator". Standalone USB isolators based upon the ADuM3160 are relatively cheap, and commonly available but operate at a maximum of USB full-speed (12 Mbit/s)
    3. USB isolators which support USB high-speed are available, but they are more expensive than the full-speed versions using a ADuM3160.

    I haven't compared the speed of debugging (time taken to download a program or single-step) using a TMDSEMU110-U connected as high-speed .vs. full-speed to know how significant that is.