Anyone know how to make a PLI?

[Xene]

HI ^^

I have a led bar graph that I want to set up as a PLI (Im sorry tim but yours wouldnt fit in my saber ^//^).Does anyone know how to make one?? I was talking to a guy at a electronics store and he said just to wire in different resistors so as the voltage in the battery drops, the lights on the bar graph go out~ this seemed to make sense but the next time I went in to purchase said resistors another guy said it wouldnt work~
and he gave me this kit (http://www.jaycar.com.au/productView.asp?ID=KA1683&form=CAT2&SUBCATID=965#11) only problem is~the min input voltage is around 10V~he said i may be able to wire it up just using the chip~any thoughts?If anyone likes I can supply a circut diagram of it (also i am planning on ditching the kits leds;))

[shmoetech]

Hey Xene I did a little research and found this dead thread it may help you...if u know how to read a schematic http://forums.thecustomsabershop.com/showthread.php?6443-RE-Power-level-indicator

[Xene]

thanks shmoetech it helps a little (I cant really read circuit diagrams too well~)what did you search to find that? I musta been looking for almost an hour~(Its probably somthing really obvious right?;))

I have a chip like the one thats mentioned but im not sure what capactors to use with it so itll run~

[xl97]

in general..you need something (maybe a microchip) that can read the the voltage of your battery pack.. and convert it to something useful.

I kno things like this are possible using an Arduino (minimal circuit..not full blown development board you buy retail of course)....

Using a ATMega328 is probably overkill and a bit big in size.. you can use an ATiny chip though..

[Xene]

As I said before I do have a chip that can do that~im just not sure what resistores/capacitors/zener diodes to add on as the pack I got them with is designed for a 10-18 volt system~

[xl97]

what chip?
wheres the link to the datasheet?

[Xene]

The chip I got with the kit I linked to in the first post~

And heres the circuit diagram for the kit~(hope you read sparky ;) )
7790

[Xene]

Update: found a eaiser circut diagram to follow :D only trick is its for a 0-5 volt system, but then again all I need to do is up the resistors a bit correct?
7844
(apolagies for leaving the diagram above~Im still not good at this whole forum/blogging thing ^//^)

[xl97]

an actual link to a datasheet will probably help more.
http://www.ti.com/product/LM3914


but maybe using a voltage divider to bring your source voltage into 'range'?

I'll be looking at this chip in the next week or so myself... :)

[Xene]

So thats what you ment by a data sheet ^//^

That could work too, but resistors are probably the eaiser option arent they? (Electronics noob XD)

Let us know how you get it to work ;D ill be experimenting with mine anyway as theyre pretty cheap~