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constant current driver

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Hi all

i have a question.

i have a LPC 826 and 1 cell lithium battery 3.7 volt 4000 ma. This question is ;

how i drive LPC 826 with only one lithium battery ?

thank you ...
 
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Thank you very much. i want build diy this driver . i need a schematic. i was build a project this link. --> http://laserpointerforums.com/f50/my-first-project-turk-88596.html

but i use a 2 battery this project. Now i build a new laser with lpc826. i think use only one battery. if i use LM317 no problem. or not i found a new shematic.

is this AMC 7135 350 ma constant current driver ? i search this part in Turkey now..

i am sory my language is bad.
 
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grainde

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Yes an AMC 7135 will regulate the current to 350 or 380 mA depending on which chip you buy. You should use one battery in this setup with an LPC-826.

You can get them from Fast tech, with free shipping and a pack of 10 cost around $ 2.40

A schematic is in the thread I posted above. Remember the regulation is on the negative ie you have continuous (+) so be careful not to short the (-) especially as the LPC-826 is case negative! :beer:
 
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i am sorry my language is not good. :(

if i try use a only one lithium battery LM 317 ?

What is it minimum supply voltage LM317 constant current driver ?

is it suitable use a only one lithium battery ? Do you anybody test it?

 
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DashApple

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i am sorry my language is not good. :(

if i try use a only one lithium battery LM 317 ?

What is it minimum supply voltage LM317 constant current driver ?

is it suitable use a only one lithium battery ? Do you anybody test it?

If its to be used as a diode driver , For a LM317 regulator to work in CC mode the voltage needs to be above the forward voltage of the laser diode ( or load ) , voltage drop over the set resistor ( 1.25V ) and around 3 volts over the regulator .

so for a 5V diode ( 445nm ) , that's 5V + 1.25V + 3V = 9.25V

Red laser diodes are around 2.2V - 2.5V , so 2.5V + 1.25V +3V = 6.25V , you could getaway with 2 Lipo cells in series for 8.4V charged ( 7.4V when at 3.7V per cell )
 
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If its to be used as a diode driver , For a LM317 regulator to work in CC mode the voltage needs to be above the forward voltage of the laser diode ( or load ) , voltage drop over the set resistor ( 1.25V ) and around 3 volts over the regulator .

so for a 5V diode ( 445nm ) , that's 5V + 1.25V + 3V = 9.25V

Red laser diodes are around 2.2V - 2.5V , so 2.5V + 1.25V +3V = 6.25V , you could getaway with 2 Lipo cells in series for 8.4V charged ( 7.4V when at 3.7V per cell )
That is very explanatory. Thank you very much. i try found AMC 7135 chip from Turkey. i can't buy international web site.
 

grainde

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Use 1 cell with the AMC chip and the LPC-826.

The above calculations were for the LM317 based driver. :beer:
 
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THE AMC 7135 chip is very simple build a laser circuit with one cell li-po battery.

So .. The other question?

What could be alternative chip or electronic parts for constant current driver ?

i will maybe found an other chip/electronic part in Turkey.
 

rhd

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THE AMC 7135 chip is very simple build a laser circuit with one cell li-po battery.

So .. The other question?

What could be alternative chip or electronic parts for constant current driver ?

i will maybe found an other chip/electronic part in Turkey.
Why can't you order from international websites? Turkey doesn't have any weird import restrictions, does it?

Good luck if you can't order internationally. I live in Canada, and it's pretty tough to find a lot of stuff without pulling from an international source.

You could maybe make do with an LM1117 + ZXCT#### current monitor, but you'll have to do some reading of datasheets, because that's not a driver setup we often use.
 
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Why can't you order from international websites? Turkey doesn't have any weird import restrictions, does it?

Good luck if you can't order internationally. I live in Canada, and it's pretty tough to find a lot of stuff without pulling from an international source.

You could maybe make do with an LM1117 + ZXCT#### current monitor, but you'll have to do some reading of datasheets, because that's not a driver setup we often use.

Because i have not credit card friend :( :(
 




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