hi,
I just made a small power circuit using the LM317. this time i am using surface mount parts on Manhattan style. I made two of the boards and rather than use a 240 ohm for R1 i used other values. the board in question uses 1300 for R1 and 3900 for R2, which given the formula would give 5 volts.
i am using a 9 volt battery for testing (will move to a wart eventually). i even omitted the diodes since i am using small value caps, and not going near 27 volts as the datasheet mentions.
with all that said, I dont understand why the output is 6.5 not 5...
[or near 5 given that parts are not perfect]
i put on a resister to give it a load, and it maintained its 6.5
[here i sit and ponder if my life will be easier when the 7805s arrive from asia]
I just made a small power circuit using the LM317. this time i am using surface mount parts on Manhattan style. I made two of the boards and rather than use a 240 ohm for R1 i used other values. the board in question uses 1300 for R1 and 3900 for R2, which given the formula would give 5 volts.
i am using a 9 volt battery for testing (will move to a wart eventually). i even omitted the diodes since i am using small value caps, and not going near 27 volts as the datasheet mentions.
with all that said, I dont understand why the output is 6.5 not 5...
[or near 5 given that parts are not perfect]
i put on a resister to give it a load, and it maintained its 6.5
[here i sit and ponder if my life will be easier when the 7805s arrive from asia]