• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 2 answers
  • Subscribers 65 subscribers
  • Views 278 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.

LM5114: Can I use INB as a "disable" control?

Brian Machesney
Prodigy 175 points
Part Number: LM5114
Other Parts Discussed in Thread: LMG1020, LMG1025-Q1, , UCC27322

I need to kill the gate drive with an disable signal. The truth table shows that P_OUT will be OPEN and N_OUT will pull 'L' whenever INB is 'H'. Are there any negative implications to using INB as a disable control for the output? For example, does INB need to be bypassed or include a ferrite bead to avoid noise injection?

  • 0
    TI__Guru**** 189399 points

    Hi, Brian,

    We have a Tech Note that discusses this!

    https://www.ti.com/lit/an/slla423/slla423.pdf

    Have you seen our newer LMG1020 and LMG1025-Q1 devices? You might consider them for your design - they are upgrades to the LM5114, AND have a shutdown pin already!

    If this answered your question, please press the green button, otherwise, let us know how else we can help you.

  • 0 in reply to Don Dapkus
    Prodigy 175 points

    Thanks for the quick response, Don. The app note answers my questions.

    I have quite a bit of experience with gate drivers. I know that training videos are all the rage but, as much as I'd like to benefit from the knowledge, I don't have time to sit through it all. Is there any way I can just view the slides?

    I've been through the TI gate driver portfolio in the past year or so but was unable to find a part that fit my needs. I need to develop 6-V of gate drive with a part that is *not* BGA and will run up to about 30-MHz.. So far, the LM5114 continues to be the only part I can find that fits. I'd be happy to learn otherwise. 

  • 0 in reply to Brian Machesney
    TI__Guru**** 189399 points

    Hi, Brian,

    Sorry, the video links are just part of my .sig, I wasn't suggesting you personally view them. For our newer videos, we do indeed load a pdf of the slides on our sites.

    The 6V is an issue. The parts I recommended have Max operating voltage of 5.5V. What kind of FETs are you trying to drive? We collaborate with EPC on our newer drivers to be compatible with their requirements.

  • 0 in reply to Don Dapkus
    Prodigy 175 points

    The parts from GaN Systems offer many advantages in my target application. Reducing gate drive from 6V significantly and adversely affects performance.

  • 0 in reply to Brian Machesney
    TI__Genius 13445 points

    Hello Brian, 

    Thanks for your interest in our drivers. 

    It sounds like your operating frequency is not fixed? am I correct? Is the 30MHz a hard requirement? I ask because given the high frequency switching, the choice in gate driver will likely lead to small package options due to factors (that you already know) like thermal and pulse width, etc...

    Have you considered UCC27322 instead? This driver is available in SOIC package, and meets your operating range (4.5V to 15V) and comes with an enable to control the output state as shown on the truth table below: 

    I do have to caution that this IC might not able to operate at the 30MHz range that you suggested but if the application is not constantly running at such conditions, this might be an option. The high drive strength 9A might also be a bonus for your application.

    Please let us know if you have additional questions.

    Regards,

    -Mamadou