sudomod

Yeah but I wasn't asking what should power it, I was asking in reference to your board design, what the positive and negative terminals should be attached to on the board itself, as your images don't appear to show any traces going to any components from power in? Maybe I wasn't being clear enough.

Zero wrote:Yeah but I wasn't asking what should power it, I was asking in reference to your board design, what the positive and negative terminals should be attached to on the board itself, as your images don't appear to show any traces going to any components from power in? Maybe I wasn't being clear enough.

I have no idea what your asking me now, the board is setup like it is in the schematic on page 2 of this thread and I already explained where negative and positive come from and go to.

I used that schematic initially and could not get it to work. Maybe there different types of 2N3904 transistors under the same name or something. I saw in another thread that a certain brand of transistor had to be used for their circuit to work the way it was intended.

Zero wrote:I used that schematic initially and could not get it to work. Maybe there different types of 2N3904 transistors under the same name or something. I saw in another thread that a certain brand of transistor had to be used for their circuit to work the way it was intended.

I used an SMD version so the pinout is always the same, if you used a traditional sot-92 then it all depends on the datasheet. The schematic is always the same it's the pinout of the actual part that changes, go look at the datasheet of the part you have for proper pinout.

Will do. Cheers.

Hi!

I've made the circuit, based on the PCB image, Gerber files and schematic (without the potmeter):
(Sorry for the hand-drawing...)

Should it so working?
Because on breadboard the LED is continuously turned on, not only when the battery is low....

lpepe wrote:Hi!

I've made the circuit, based on the PCB image, Gerber files and schematic (without the potmeter):

FullSizeRender.jpg

(Sorry for the hand-drawing...)

Should it so working?
Because on breadboard the LED is continuously turned on, not only when the battery is low....

Well if you added the battery positive to the 5V point and the negative to the GND point it should only light up when it's at or below 3.26v.
Post an image of your bread board and are you sure you're using the correct value resistors?

Helder wrote:

lpepe wrote:Hi!

I've made the circuit, based on the PCB image, Gerber files and schematic (without the potmeter):

FullSizeRender.jpg

(Sorry for the hand-drawing...)

Should it so working?
Because on breadboard the LED is continuously turned on, not only when the battery is low....

Well if you added the battery positive to the 5V point and the negative to the GND point it should only light up when it's at or below 3.26v.
Post an image of your bread board and are you sure you're using the correct value resistors?

I think, the transistors are the same, that you used:
http://www.produktinfo.conrad.com/daten ... 92_FSC.pdf

Looks alright to me, is your battery charged? do you have a multimeter to show how much voltage it has? Also try a pot like in the first schematic I posted and mess with the values to see when it lights up at the battery voltage when it's low and take the measurements with a multimeter of the POT to get the resistor values.

Helder wrote:Looks alright to me, is your battery charged? do you have a multimeter to show how much voltage it has? Also try a pot like in the first schematic I posted and mess with the values to see when it lights up at the battery voltage when it's low and take the measurements with a multimeter of the POT to get the resistor values.

Of course, it's charged. With potmeter didn't tried yet, I didn't ordered one....

I used a 18650 li-ion battery, but I think this isn't the problem? (the battery is brand new Samsung cell...)