the guy who told me to use the LM317 (TO-3 package) insists that it can handle up to 3A... and it's up to me if i prefer to use LM350K which of course it's better.
i wanted to buy lm350 in TO-220 package but again insisted that this plastic thing it is impossible for it to work fine with 3A and i better get the TO-3 version.
what's the difference between LM350 in TO-3 and TO-220 packages? i don't see any difference other than that the first is case mounting component.
The TO-220 case can handle 3A or they wouldn't specify it... however the heatsink is critical. I am using the TO-220 LM350T in a circuit with a decent but not huge heatsink which gets extremely warm when running at more than 1A despite my application staying within the 3-4.5A Vin-Vout band in the specs.
I would advise you to use one of the larger TO-220 heatsinks and to measure the temperature at full current draw for your application. You may be surprised...
No.
Look at the datasheet. Its max thermal resistance is 4 degrees C per Watt. If you have 10V input to output and 3A then it must dissipate 30W. But if it has a pretty good heatsink that is 1 degree per Watt and the ambient temperature is 25 degrees C then it reaches its max allowed temperature of 125 degrees C with only 20W. So its max current is only 2A or you must limit the coltage across it.
The TO-3 case has a thermal resistance of only 1.5 degrees C per Watt so if it has a pretty good heatsink that is 1 degree per Watt and the ambient temperature is 25 degrees C then its chip temp is only 100 degrees C when it dissipates 30W.
i mean i can output 3A if of course the voltage difference is less than 10V?
No.
Look at its datasheet. The LM317 will give at least 1.5A when it has 15V or less input to output. But the To-220 case limits its dissiapation to about 20W with a pretty good heatsink. The TO-3 case can dissipate 25W.