Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

possible 3$ boost circuit

iccy

0
Joined
Jun 13, 2008
Messages
110
Points
16
I was messing around with the 1aaa rayovac penlight.
The exact same one found http://www.flashlightz.com/product.php?product=171701. Except I got mine from Wal-Mart for $3.88

The first one i bought i measured 78 mA. I removed the resistor and measured over 200mA.. I couldnt tell you how much because my multimeter only goes up to 200mA.
I accidentally broke it (lol), so I got another one and a new multimeter. Here are the results after removing the resistor.


Soldering where the resistor used to be.
DSCF0944.jpg

I hooked up test leads
DSCF0947.jpg

set multimeter to 10A, reading 400mA?
DSCF0951.jpg

This would be an awesome laser 400mA with open can diode using only 1aaa!
I was thinking about making it into a laser, do you guys think its safe?
 





Joined
Aug 20, 2008
Messages
709
Points
0
Probably isn't a boost circuit. There should either be an inductor or a few capacitors(charge pump) and an boost converter chip.
 
Joined
Feb 22, 2008
Messages
3,182
Points
48
yea what jamilm9 said it has to be above the required volt rating of the ld you are using
 
Joined
Jan 12, 2008
Messages
3,290
Points
83
The output is probably very noisy, full of spikes and such. Maybe not ever regulated, so I'd say no. But maybe there's some room for improvements. :)

digital_blue said:
Probably isn't a boost circuit. There should either be an inductor or a few capacitors(charge pump) and an boost converter chip.
LEDs need more than 1.5V to work so it must be a boost driver.
 
Joined
Mar 8, 2008
Messages
2,669
Points
48
Voltage is the question here. A single AAA can easily put out 400mA, and probably a lot more, the problem is that it is only at 1.5VDC (although I dont think a LED will work at 1.5V... maybe?). Now if it can boost to 3-5VDC and still do 400mA, that will be impressive!
 

Ace82

0
Joined
Feb 11, 2008
Messages
1,768
Points
0
It looks regulated, and I believe a diode could run from 1.5V @400ma. Doesn't look like a boost circuit though. :(
 

Benm

0
Joined
Aug 16, 2007
Messages
7,896
Points
113
It's entirely possible it is a boost circuit capable of delivering that much as long as the batteries supply plenty of input current.

One question is: is it regulated? What is the current at 1.0, 1.2 or 1.5 volts? And what is the current driving different voltages (try 1n400x diodes in series as dummies).
 
Joined
Oct 14, 2008
Messages
233
Points
0
I believe I've seen ~3.5V boost chips that looked like the chip on the back, but I've yet to see a 5V boost chip in that form factor.  If someone does see one, please let me know.

Edit: There are ways to achieve more than 3.5 V out of a chip like that, but the output would not have good regulation.
 

iccy

0
Joined
Jun 13, 2008
Messages
110
Points
16
Testing... Ill post results when done

DSCF0957.jpg




     BATTERY                                    VOLTAGE AFTER CIRCUIT                  CURRENT AFTER CIRCUIT
Duracell at 1.60v                          -> in between 3.76v and 3.77v, briefly at 420mA and then receded to 400mA within a few seconds.
DSCF0959.jpg
             
DSCF0961.jpg
             
DSCF0962.jpg













DSCF0956.jpg







BATTERY VOLTAGE              VOLTAGE AFTER CIRCUIT    CURRENT AFTER CIRCUIT
Duracell rechargeable 1.45v      ->    3.71v,                                340mA
DSCF0960.jpg
DSCF0964.jpg
 
DSCF0963.jpg
 
Joined
Nov 24, 2007
Messages
65
Points
0
you said you removed a resistor. maybe it is a voltage regulated boost circuit and the resistor was for current limiting.
 




Top