• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 489 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

TPS92515HVEVM-749: Test with 1 Ohm load power resistor

Marcin Brylak
Prodigy 205 points
Part Number: TPS92515HVEVM-749

Dear TI,

I did some test of your EvalBoard and LED current on 1 Ohm resistor looks not good. I used Vin= 26 V and PWM= 5V (continually). With 1.5A resistor divider setup I see only glitches till 1.7A and current goes back to zero. Do you have any suggestions?

Thanks a lot

BR

Marcin

  • 0
    TI__Mastermind 25500 points

    Hello Marcin,

    Resistive loads behave very differently than LED loads. LEDs will conduct very little current below their Vf whereas a resistor will continue to conduct. In this case it is also a very low value resistor. So what is happening is the output just exceeds the 1V OFF threshold but then drops below it before the OFF time expires (charges up to 1V) so you are operating in maximum off time.

    A higher resistor value might do the trick as long as the output voltage doesn't drop below 1V during the off time, but if you use an LED load it will operate much better since the output will stay charged much better and keep the OFF time more regular.

    Regards,

    Clint