• State
  • Locked Locked
  • Replies 2 replies
  • Subscribers 32 subscribers
  • Views 526 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.

ISO5500 breaks after debuging the microcontroller

Siegfried Schneider
Prodigy 20 points

Hi,

the ISO5500 runs as expected until I begin to debug the microcontroller. After that the +15V and -15V are shorted. What could have happened that the ISO5500 breaks down? Schematic attached.

  • 0 in reply to Siegfried Schneider
    TI__Intellectual 2200 points

    Hi Siegfried,

    Can you please provide more information on what you observe before or at the point of failure, in terms of waveforms on the device pins? Without this information it is difficult to say what might been causing the problem.

    But before that, could you please make the following changes to your design, and try again:

    1. Replace R5 by a zero-Ohm resistor i.e. short to GND, or include a 100pF capacitor in parallel with R5. This is to create a low impedance path for any noise on DESAT pin.

    2. Replace R15 by a 12 Ohm resistor. This is to limit the worst case current output to 2.5A.

    3. I did not understand the purpose of C18. What is connected on VOUT? The correct way to check functionality is to include a 10nF cap to GND to R15, and measure voltage across this cap.

    Rgds,

    Anant