I agree. We need better specs on how much current the load requires at ~1.5V?... the LM317 is the wrong way to go. Very inefficient regulator.
What is the source of the 6V? If it is another battery then the LM317 is the wrong way to go. Very inefficient regulator.
Ah you need 3V out?? Thought you needed 5v My 34068 works at 7v in with 5V out, so I am sure it would work 6V to 3V. I would need to change out the sensor resistors to get 3v out.
If you want 3v, why not get a 2 cell battery pack?
You obviously did not read or heed the advice I gave you in post #20!...I then changed R2 resistor to a 220 to get me a starting voltage of 3.5 (need at least 3v to bring the device out of sleep mode and with the 180 I was barely getting that), and the best part is now when everything is 1st powered on there is 3.5v which is more than enough to wake the transponder, and when the load of the transponder is applied to the circuit it drops the voltage to 2.45. ....
Why not a simple schematic instead of the so many words as above? Believe me, it is better for anyone discussing the same thing.Atferrari, my current version is I have the Vout leg of the LM317 soldered to the positive side of the battery connector in the transponder. I have a 120ohm resistor for R1 soldered directly to the legs of the LM317. I have a 220ohm resistor for R2 soldered from the adj leg to the negative side of the original battery connector. I have 1 wire of a harness soldered to the negative pin of transponder and the other wire of the harness soldered to the Vin leg of the LM317 that will plug into my receiver to get power from. Everything works when powered off 4AA's. I didn't have a vehicle with a receiver in it last night to actually try it how it will be used, but I'm confident it will work just the same.
Because I suck at drawing. I'll see if I can draw something up.Why not a simple schematic instead of the so many words as above? Believe me, it is better for anyone discussing the same thing.
I fail to see why all of this energy is being wasted on the LM317 when it is the wrong way to go. A linear regulator is simply not the best solution for this application.
OP,
Take a look at one of these
http://www.ebay.com/itm/1pc-Buck-Co...hash=item3cdb07b8a8:m:m6d7bbXlK87smCwKgY3Pq7A
This one is adjustable. You might be able to find one with set 3V out but all I could find is 3,3V. But keep searching maybe one is out there. If not then you have the adjustable solution.
This will be your easiest and most efficient solution to this problem.
by Aaron Carman
by Aaron Carman
by Jake Hertz
by Jake Hertz