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Min voltage on ddl driver, 2x lithiums ok?

Eudaimonium

Eudaimonium

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Hiya all, I wuz just going to order 2 14500 lithiums, for stuffing my neat bluray into some flashlight host that is using AA's so, 2x 14500 is 7.2 V average, is it going to be enough?

My friend told me he strictly used 9 V on ddl and PHR, and that he THINKS it ain't gonna be enough, but he never actually tried it.

So anybody tried 2x lithiums in ddl and PHR? about 90 ~100mA of course.

Wuz told that DDL should have like... 3 V difference diodeV-power source.
Diode is like 5 or 6 V, so far i used 9V batt . However , I'm 1.8 V short.
Somebody please I'm wrong.
 





iskor12

iskor12

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It should work ok. Starting voltage will be 8.4V and will end at around 5.8V. The downfall of only using two of these batteries is that from the start of using your laser....the current will slowly decrease as the voltage of your batteries decrease, thus the output of the laser will go down slowly from the very begining of turning it on.
 
HIMNL9

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Also, build your driver using an LDO regulator can help you.

As example, if instead the common LM317, you use an LM1117 (note, not 117, but 1117 :p), it drop less volts from the battery, so you can use it also with some less input voltage ..... as example, LM117-217-317 based ones, that have a maximum dropout of 2,2V, if you want to use it with a diode that have a FV of 5V, minimum useable input voltage must be 7,2 V, better 7,5 or more ..... with LM1117, that have a maximum dropout of 1,2V, with the same diode, you need a minimum voltage of 6,2V (considerate 6,5V), so also batteries a bit discharged give better results ..... and the pinout is identical, so any schematic that use the 317, is valid also for the 1117 :)
 
Eudaimonium

Eudaimonium

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iskor12 said:
It should work ok. Starting voltage will be 8.4V and will end at around 5.8V. The downfall of only using two of these batteries is that from the start of using your laser....the current will slowly decrease as the voltage of your batteries decrease, thus the output of the laser will go down slowly from the very begining of turning it on.
Click to expand...
Well i knew that and i don't mind as long as it is working. That also goes in favor of laser's lifetime. I'm not one of those that want every single photon outta their diode. Thanx for the info though. + rep :D
HIMNL9 said:
Also, build your driver using an LDO regulator can help you.

As example, if instead the common LM317, you use an LM1117 (note, not 117, but 1117 :p), it drop less volts from the battery, so you can use it also with some less input voltage ..... as example, LM117-217-317 based ones, that have a maximum dropout of 2,2V, if you want to use it with a diode that have a FV of 5V, minimum useable input voltage must be 7,2 V, better 7,5 or more ..... with LM1117, that have a maximum dropout of 1,2V, with the same diode, you need a minimum voltage of 6,2V (considerate 6,5V), so also batteries a bit discharged give better results ..... and the pinout is identical, so any schematic that use the 317, is valid also for the 1117 :)
Click to expand...
Hmmm 1117 ?! Never heard of it. Why is it so that LM317 is so popular if 1117 is better? Also, as far as i understood from your post, i just desolder 317 and solder on 1117? If 1117 really has half of Vdrop, that is one hell of a bluray driver. Now i know what i must get my self on next visit to electronics store. Thank you also, + rep

EDIT: Yeah, forgot to ask, DealExtreme has very good price od 14500's and charger BUT i could not find the charger with EU plug format. So I'll get batteries from DX, and if anyone can gimme the link, or better yet sell a EU plug chord (or charger itself) I would very much appreciate it.
 
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Eudaimonium

Eudaimonium

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Hell!! Why couldn't I find it?? It must have been lookin' into my new Blu ray a little too much ... :D

Thank you very much! Page bookmarked, scrapin' some coins together...

Ok,
batteries = 5.56 $
charger= 8.81 $
powerchord= 3.55$
Thermal paste= 3.25 $
_____________________
Subtotal = 21, 17 $
:= 103 HRK
DAAAMN. I'm'a go bankrupt soon. If not sooner
:D:D
 
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HIMNL9

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1117 is less popular cause it's a relatively new product, where instead LM317 serie is on the market from half of a life (almost :p) ..... as example, i can find 317 in any electronic shops, but for get the 1117 in TO252 that i use abitually, need to buy them on ebay :p

Yes, Vref is the same, so you can just desolder the 317 and solder the 1117 in place of it, and the current regulation remain the same.
 
Eudaimonium

Eudaimonium

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HIMNL9 said:
1117 is less popular cause it's a relatively new product, where instead LM317 serie is on the market from half of a life (almost :p) ..... as example, i can find 317 in any electronic shops, but for get the 1117 in TO252 that i use abitually, need to buy them on ebay :p

Yes, Vref is the same, so you can just desolder the 317 and solder the 1117 in place of it, and the current regulation remain the same.
Click to expand...
DUUUDE! With the same 33 Ohm between OUT and ADJ on 317 and 1117, same 90 mA on both?! Holy... Gotta get a crapload of these!!
Good bye 317, 9V, ugly hosts and powr problems!
Hello new era of DDL drivers...
 
Tabish

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A DDL driver CAN work for a PHR with 2x 3.6v batts.
At full charge they are 4.2v each. Just don't let them drop below 3.5v.

Never heard of the 1117. Can I swap the 317 for a 1117 on the rkcstr driver ???
 
Eudaimonium

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Tabish said:
A DDL driver CAN work for a PHR with 2x 3.6v batts.
At full charge they are 4.2v each. Just don't let them drop below 3.5v.

Never heard of the 1117. Can I swap the 317 for a 1117 on the rkcstr driver ???
Click to expand...
It appears that you can, I went through some datasheets (not with my laser, read the m :D) and it appears it is acctually better and improved 317, because 317 is often mentioned through 1117 datasheet for reference.
Definetly gettin to A/D ELECTRONIC in tommorow.
 
Tabish

Tabish

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Awesome!
A dropout voltage of 1.2v would work perfectly for 2 cells (thx for that info HIMNL9)

Anyone know where I can order one ??
 
Eudaimonium

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Tabish said:
Awesome!
A dropout voltage of 1.2v would work perfectly for 2 cells (thx for that info HIMNL9)

Anyone know where I can order one ??
Click to expand...
Dude sad he is using Ebay, however I'm'a check local electronic stores first.

EDIT: BTW if I happen to find a large quantity, let's do some math and see maybe it will come cheaper if i picked up some for you and send you, if they are not too expensive you just pay the shipping I'm gonna send 'em for free.
Deal?
 
Tabish

Tabish

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Eudaimonium said:
Dude sad he is using Ebay, however I'm'a check local electronic stores first.

EDIT: BTW if I happen to find a large quantity, let's do some math and see maybe it will come cheaper if i picked up some for you and send you, if they are not too expensive you just pay the shipping I'm gonna send 'em for free.
Deal?
Click to expand...

Deal!!! Thanks. Btw, I'l pay you for em.

They should be cheap though at a electronics shop (the ones that sell cheap electronic parts, unlike radioshack)


Sucks that I don't have any electronic shops nearby :(
 
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Eudaimonium

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Tabish said:
Deal!!! Thanks. Btw, I'l pay you for em.

They should be cheap though at a electronics shop (the ones that sell cheap electronic parts, unlike radioshack)


Sucks that I don't have any electronic shops nearby :(
Click to expand...
Well i have this one and it has everything, i will check if they have 1117 (i have sent email but got no reply so far) i will be getting my self 10 pcs or maybe less, so if i find 'em how many do you need?

Just checked ebay, 4 $ 10 pcs plus shippement.
It is not exactly a fortune :D
Just say how much do you need, and you just pay for the shippement, and they are on their way ... the day after tommorow, since tommorow i will go to the store.

However we still don't know if I'm gonna find them there...
Let's hope so.
 
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Tabish

Tabish

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Cool, thanks again.

I'll take like 3.

These + rkcstr driver would work perfectly with 2 cells.
Good cheap alternative to flexdrives :)
 
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Eudaimonium

Eudaimonium

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Tabish said:
Cool, thanks again.

I'll take like 3.

These + rkcstr driver would work perfectly with 2 cells.
Good cheap alternative to flexdrives :)
Click to expand...
Only 3??
Well right now i would go off like: I'm'a give you 5
if i weren't in doubt will i even find them in the shop, it would turn out pretty stupid that after: you can have 5 for free i turn up tommorow:"Sorry no 1117 :("

Croatian saying: "Hold your thumbs!" goes here :D

Oh yeah, BTW there maybe only TO220 package available, if so, you still want them?
 
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