Huh? Can you elaborate on the letter "c"?----------------
ok, so, I'm using the Radio Shack V-Reg... I"m going to dump that idea, and hold off for either the TI V-Reg, or, just use a 2w resistor..
Hmm...5v box mod question
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Huh? Can you elaborate on the letter "c"?----------------
ok, so, I'm using the Radio Shack V-Reg... I"m going to dump that idea, and hold off for either the TI V-Reg, or, just use a 2w resistor..
Hmm...Can you use (2) rcr123a 3v batteries with the LM7805c? I'm trying, but it's just not working. Do you need a higher voltage for it to operate? I see in the pics that you are using 7.2v total. Is 6v to low for the input?Data sheet for LM7805c shows 10v input with 5v output, and also says you need Min 7.5v input to maintain line regulation. That's cutting it close. You're better off with the Texas Instruments part. It has perfect specs for an ecig. In fact if you register with TI.com, they will send you up to 5 samples of this part totally free, they even cover shipping.
Data Sheet for LM7805c
http://www.datasheetcatalog.org/datasheet/nationalsemiconductor/DS007746.PDF
TI.com samples (Scroll to top of page for part specs)
Linear Regulators - Single Channel LDO - UCC383-5 - TI.com
I thought you have built a 5V mod using MadVapes KA378R05 full 3A regulator? You said it worked well. What's the deal?
Oh yes, I did built a couple of them using MadVapes regulators. They work great! But I'm always up to try new things. I'm working on another design and received the TI regulators free in the mail. I can't order MadVapes until Friday! Then I have to wait to receive them. That's all. Figured I'd try what I have!
Forget about the 7805, and don't even mess with it. It doesn't have good specs for an e-cig anyway. Since you now have the TI regulators, use it instead. Works much better then the 7805. And yes, you're much better off with two 3.7v batteries instead of two 3v batteries.
But, is 6v too low for the TI regulator? Does it need the higher voltage like 7.4v to work?
So, what do I use that is the same size as (2)rcr123a 3v batteries?
Fully charged they are 4.2 volts, but they drop pretty quick. You'd probably only get half an hour before you hit the dropout.
I just put in a Texas Instruments 5v regulator UA7805CKTTR and am running it off of (2) rcr123a 3v batteries. It's giving me a perfect 5v and the amps through the connector, not the atty, is 1.45amps. It give a great amount of vapor and taste. Just tried one of the regulators they sent me, and it worked!
Glad your up and running. Let us know how long it lasts with the 3volt batteries.
Will do! I hope the batteries last as long on these as they do on MadVapes 4pin regulators. We will see!
Someone earlier said the TI regulators need a min of 7.5v, but that's not right. The TI UCC383 has a min Vin of 5.45v.
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