Old 08-05-2009, 09:27 AM #1
zxn474l's Avatar
Class 1M Laser
 
Join Date: Jan 2009
Posts: 204
Rep Power: 12
zxn474l has a spectacular aura aboutzxn474l has a spectacular aura aboutzxn474l has a spectacular aura about
zxn474l zxn474l is offline
Class 1M Laser
zxn474l's Avatar
 
Join Date: Jan 2009
Posts: 204
Rep Power: 12
zxn474l has a spectacular aura aboutzxn474l has a spectacular aura aboutzxn474l has a spectacular aura about
Smile current/9 volt battery and diodes

What is the total aproximate current from a typical 9volt battery? In a parrallel ciruit using just one 9 volt battery and powering three diodes all in parralell with each other would the total current from the 9 volt battery be divided by 3 and each diode recieve a 1/3 of the current from the battery at 9 volts which is well under the max ma for any one diode?


zxn474l is offline   Reply With Quote


















Old 08-05-2009, 09:39 AM #2
ThunderBird89's Avatar
Class 1M Laser
 
Join Date: Mar 2009
Location: Hungary
Posts: 145
Rep Power: 10
ThunderBird89 will become famous soon enough
ThunderBird89 ThunderBird89 is offline
Class 1M Laser
ThunderBird89's Avatar
 
Join Date: Mar 2009
Location: Hungary
Posts: 145
Rep Power: 10
ThunderBird89 will become famous soon enough
Default Re: current/9 volt battery and diodes

There's no such thing as 'current for a 9V battery'. Current is voltage divided by resistance, so you need the resistance of the circuit, or at least one diode to calculate the current.
ThunderBird89 is offline   Reply With Quote
Old 08-05-2009, 12:36 PM #3
Gryphon's Avatar
Class 3R Laser
 
Join Date: May 2009
Location: Panama City, Florida
Posts: 1,838
Rep Power: 183
Gryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond repute
Gryphon Gryphon is offline
Class 3R Laser
Gryphon's Avatar
 
Join Date: May 2009
Location: Panama City, Florida
Posts: 1,838
Rep Power: 183
Gryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond reputeGryphon has a reputation beyond repute
Default Re: current/9 volt battery and diodes

Also, i have my doubts about each diode recieving 1/3 of the total output without some sort of current regulation. I believe that more current will simply flow to the diode(s) which offer the least internal resistance, or basically the most effecient of the bunch.
__________________
I see................wait, what now?

(3x) 405nm
(6x) 445nm
(4x) 532nm
(1x) 543nm
(1x) 632.8nm
(1x) 635nm
(3x) 660nm
SSY-1 Laser
Gryphon is offline   Reply With Quote
Old 08-05-2009, 01:43 PM #4
ThunderBird89's Avatar
Class 1M Laser
 
Join Date: Mar 2009
Location: Hungary
Posts: 145
Rep Power: 10
ThunderBird89 will become famous soon enough
ThunderBird89 ThunderBird89 is offline
Class 1M Laser
ThunderBird89's Avatar
 
Join Date: Mar 2009
Location: Hungary
Posts: 145
Rep Power: 10
ThunderBird89 will become famous soon enough
Default Re: current/9 volt battery and diodes

That's the least of his problem, I think, but true: you always need some sort of active current regulator. Depending on the forward bias of the diode and the budget, I'd say a RckStar driver, with its output split threeways would do the thing, no? Although the input power would probably have to be raised to three 9V batteries, but at least it's massively durable, and hard to damage short of catastrophic overvolt.

Or if you want to go safe, and you have the money, you could order three FlexDrives, which are buck-boost drivers, so they will always keep the current and voltage at the proper setting, but are easy to overload and short out. However, with pulldown resistors and a lot of calculation, you should be able to split a 9V input into three, each of which is palatable for a FlexDrive

It's your choice really
ThunderBird89 is offline   Reply With Quote
Old 08-05-2009, 06:04 PM #5
HIMNL9's Avatar
Class 4 Laser
 
Join Date: May 2009
Location: Lost somewhere in the EU mess ;)
Posts: 5,416
Rep Power: 1479
HIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond repute
HIMNL9 HIMNL9 is offline
Class 4 Laser
HIMNL9's Avatar
 
Join Date: May 2009
Location: Lost somewhere in the EU mess ;)
Posts: 5,416
Rep Power: 1479
HIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond reputeHIMNL9 has a reputation beyond repute
Default Re: current/9 volt battery and diodes

probably he means the maximum current that a 9V-type battery can give ..... old types, zinc-carbon, was something like 50 / 100 mA, the alkaline ones can give like 200 / 300 mA or few more (don't really think much more) for a short period of time.
__________________
High Impulse Multipath Neutron Laser (mark 9 ) (LOL)
Dare mo mita koto no nai, kaze, kumo, suna, umi ..... Kokoro no hate no doko ka eien ga kagayaku.
HIMNL9 is offline   Reply With Quote
Old 08-05-2009, 06:34 PM #6
ThunderBird89's Avatar
Class 1M Laser
 
Join Date: Mar 2009
Location: Hungary
Posts: 145
Rep Power: 10
ThunderBird89 will become famous soon enough
ThunderBird89 ThunderBird89 is offline
Class 1M Laser
ThunderBird89's Avatar
 
Join Date: Mar 2009
Location: Hungary
Posts: 145
Rep Power: 10
ThunderBird89 will become famous soon enough
Default Re: current/9 volt battery and diodes

So not really much, especially if it has to power three diodes. Still, he should use some sort of current regulator, just to keep those diodes safe. I certainly wouldn't power them up with just a limiting resistor in series with each...
ThunderBird89 is offline   Reply With Quote
Reply





Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



























Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 02:35 PM.


Powered by: vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO
Privacy Policy | Advertising Disclaimer | Terms of Use
Copyright (C) 2017 Laser Pointer Forums, LLC