So the mouser datasheet I'm looking at is being kind of vague on what's the max amps I pull from the LM317. Any ideas?


http://www.mouser.com/ds/2/389/lm217-974117.pdf

 

Nothing vague about it; under Maximum Ratings it says the maximum output current is internally limited. That means that the LM317's internal circuitry will limit the current (i.e., by reducing the output voltage) to a safe value. The maximum power dissipation of the chip is also internally limited to a safe value (presumably by monitoring the die temperature).

Under Electrical Characteristics, the Maximum Load Current is listed as 1.5 amps minimum, 2.2 amps typical. That says the internal current limiting will allow you to draw at least 1.5 amps, and in most cases 2.2 amps.

The safe thing to do (to avoid bitter disappointment) is to not count on getting any more than 1.5 amps from the device.

 

Hello,

In the electrical data there is clearly given the typical output current for two cases:



There is even a graph that shows the max output current for the different dropout voltages:



Bertus

 

So the mouser datasheet I'm looking at is being kind of vague on what's the max amps I pull from the LM317.

What do you consider is "kind of vague"?

 

So the mouser datasheet I'm looking at is being kind of vague on what's the max amps I pull from the LM317. Any ideas?

Conservative designers always use the worst case value specified by the manufacturer. Using anything else requires incoming testing to test for the desired characteristic(s).