• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 62 subscribers
  • Views 2696 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.

LM317: alternative part LM1086

Adrian Ymeraj
Expert 3810 points
Part Number: LM317
Other Parts Discussed in Thread: LM1086

Hello team,

I'm using the LM317 in TO-220 package but due to the dropout voltage, I wanted to change p/n to something like LM1086. Do you think it's a good fit?

Requirements are package and pinout must be the same as the LM317; Vinmax=30V, Iout=1.5A, Vout=15V.

Thanks and best regards,

Adrian

  • 0
    TI__Guru 55940 points
    Hi Adrian,

    LM1086 looks like it could be an option; however, I am not sure that I understand your concern with dropout voltage with LM317. What is your minimum expected Vin?

    Very Respectfully,
    Ryan
  • 0 in reply to Ryan Eslinger
    TI__Expert 3810 points
    Hello Ryan,

    sorry for the late reply. The main issue with the LM317 is that the dropout is excessively high: in our application the 15V line is generated by a winding of a slightly disadvantaged transformer, which in low load conditions on the power supply gives as an input to the LM317 a voltage equal to 16.7V . As a result, the 15V line is not correctly adjusted until the "main" outputs of the power supply are loaded properly.
    Thus my interest in a regulator with a smaller dropout, in order to reduce this problem. This is why 1086.

    Hope this makes sense. We will test the LM1086 for now unless you recommend something different.

    Best regards,
    Adrian
  • 0 in reply to Adrian Ymeraj
    TI__Guru 55940 points
    Hi Adrian,

    Thank you for the additional information. Since it looks like your minimum Vin is 16.7 V and the maximum specified Dropout Voltage for LM1086 is 1.5 V, I would agree LM1086 is a good candidate for you to consider.

    Very Respectfully,
    Ryan