No announcement yet.

Linear regulators

  • Filter
  • Time
  • Show
Clear All
new posts

  • Linear regulators

    Ok, now I have used the search button and cant find a simple answer to this question.... Why do the linear 5v voltage regs get so hot? Is it the current draw from the load or is it the 7v (12v in for 5v out)it has to disapate as heat? Or is it a little of both. What if I could get the input to a regulated 8v, would it run a little cooler.

  • #2
    Thats strange, because my 5V regulators get barely luke warm around under load (~6A) and operation for about 2hrs... i have a big aluminum heatsink on it, thermal transfer paste, and a strong bolt to hold the regulator... perhaps you should reconsider your heatsink

    2001 PT Cruiser "BLK ICE"


    • #3
      The two factors which go into deciding the power dissipation of a linear regulator are the voltage it has to drop, and the current it has to supply. Multiply these two numbers together and you have the power dissipation.

      Reducing the amount it has to drop would help a lot. Typically regulators in cars have to drop from 14.4v, not 12v. You'll find that the battery voltage with the engine running is higher...

      Old Systems retired due to new car
      New system at design/prototype stage on BeagleBoard.


      • #4
        Thanks, that exactly what I was looking for.