Low Battery LED Indicator Board [OSHPark]

Completed sale threads will be moved here to keep things tidy in the main For Sale forum.
User avatar
Camble
Posts: 879
Joined: Thu May 05, 2016 2:31 am
Location: Scotland
Has thanked: 269 times
Been thanked: 487 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Camble » Wed Aug 10, 2016 6:58 am

I think the important thing here is the current limiting resistor for the LED. You're right when you say the 33k resistors should be fine, and the potentiometer is just a voltage divider so they should all be fine.

User avatar
Helder
Trailblazer
Trailblazer
Posts: 2749
Joined: Thu May 05, 2016 8:33 am
Location: Fall River, MA
Has thanked: 1402 times
Been thanked: 3069 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Helder » Fri Aug 12, 2016 1:37 pm

Camble wrote:I think the important thing here is the current limiting resistor for the LED. You're right when you say the 33k resistors should be fine, and the potentiometer is just a voltage divider so they should all be fine.
Values I posted seems fine and here is the image of it with normal battery and low battery:

Image


Image
My Sale Threads:

Retro PSU, 3.5A output!


Chat with me and other members


Don't contact me about obtaining my board files (as you will not get them). Don't contact me about any of my boards if they are sold out, they will be restocked as soon as I can get them.


Don't support thieves like ckliang who copied my AIO to resell and is now cloning the mintyPi, support the original creators and not the thieves!

User avatar
Helder
Trailblazer
Trailblazer
Posts: 2749
Joined: Thu May 05, 2016 8:33 am
Location: Fall River, MA
Has thanked: 1402 times
Been thanked: 3069 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Helder » Sat Aug 13, 2016 4:47 pm

Added 2 more boards to original post where there is no pot to tweak and it will come on at 3.26V. The boards are a little more low profile because of the missing pot which is better overall for this project, the original boards are more versatile for many applications besides this one but can still be used for this project.
My Sale Threads:

Retro PSU, 3.5A output!


Chat with me and other members


Don't contact me about obtaining my board files (as you will not get them). Don't contact me about any of my boards if they are sold out, they will be restocked as soon as I can get them.


Don't support thieves like ckliang who copied my AIO to resell and is now cloning the mintyPi, support the original creators and not the thieves!

username 123
Posts: 134
Joined: Thu Jun 09, 2016 5:45 pm
Has thanked: 33 times
Been thanked: 29 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by username 123 » Sat Aug 13, 2016 11:15 pm

Once I find that magic pot value to make the led go on around 3.26 volts, can I replace the pot with a resistor of that same value?

User avatar
Helder
Trailblazer
Trailblazer
Posts: 2749
Joined: Thu May 05, 2016 8:33 am
Location: Fall River, MA
Has thanked: 1402 times
Been thanked: 3069 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Helder » Sun Aug 14, 2016 5:47 am

username 123 wrote:Once I find that magic pot value to make the led go on around 3.26 volts, can I replace the pot with a resistor of that same value?
The values are what I have on the new boards but because it's an off value you need 4 resistors in series, well 2 in series on one end and 2 in the other end.

If you want to get some approximate values close enough then use 7.5K and 2k where the pot is like so:

Image
My Sale Threads:

Retro PSU, 3.5A output!


Chat with me and other members


Don't contact me about obtaining my board files (as you will not get them). Don't contact me about any of my boards if they are sold out, they will be restocked as soon as I can get them.


Don't support thieves like ckliang who copied my AIO to resell and is now cloning the mintyPi, support the original creators and not the thieves!

username 123
Posts: 134
Joined: Thu Jun 09, 2016 5:45 pm
Has thanked: 33 times
Been thanked: 29 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by username 123 » Sun Aug 14, 2016 8:55 am

Helder wrote:
username 123 wrote:Once I find that magic pot value to make the led go on around 3.26 volts, can I replace the pot with a resistor of that same value?
The values are what I have on the new boards but because it's an off value you need 4 resistors in series, well 2 in series on one end and 2 in the other end.

If you want to get some approximate values close enough then use 7.5K and 2k where the pot is like so:

Image
I have the smd version. Hopefully this will work.

Zero
Posts: 157
Joined: Fri Sep 02, 2016 6:32 pm
Location: Bristol, UK
Has thanked: 11 times
Been thanked: 35 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Zero » Fri Sep 09, 2016 5:46 am

I found that I had most of the components with the same values as shown in the parts list scavenged from old electronics so thought I'd try making one of these handy little circuits, but I'm a bit confused as the positive and negative terminals don't appear to attach to anything in the diagram. Or maybe I'm reading it incorrectly? I'm not great with electronics unfortunately. :roll:

Also can variable pots of higher values be used in this circuit instead of a 47k one? I assume that as they can be adjusted, maybe 100k could be a substitute perhaps?

User avatar
Helder
Trailblazer
Trailblazer
Posts: 2749
Joined: Thu May 05, 2016 8:33 am
Location: Fall River, MA
Has thanked: 1402 times
Been thanked: 3069 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Helder » Fri Sep 09, 2016 7:22 pm

Zero wrote:I found that I had most of the components with the same values as shown in the parts list scavenged from old electronics so thought I'd try making one of these handy little circuits, but I'm a bit confused as the positive and negative terminals don't appear to attach to anything in the diagram. Or maybe I'm reading it incorrectly? I'm not great with electronics unfortunately. :roll:

Also can variable pots of higher values be used in this circuit instead of a 47k one? I assume that as they can be adjusted, maybe 100k could be a substitute perhaps?
You attach the battery to those then from those you go to the power supply board. You can use anything over 10k pot but the tweaking of it will be more sensitive as the range in the pot value is much greater so a small turn will cover a larger range of values than on the 10k pot.
My Sale Threads:

Retro PSU, 3.5A output!


Chat with me and other members


Don't contact me about obtaining my board files (as you will not get them). Don't contact me about any of my boards if they are sold out, they will be restocked as soon as I can get them.


Don't support thieves like ckliang who copied my AIO to resell and is now cloning the mintyPi, support the original creators and not the thieves!

Zero
Posts: 157
Joined: Fri Sep 02, 2016 6:32 pm
Location: Bristol, UK
Has thanked: 11 times
Been thanked: 35 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Zero » Sat Sep 10, 2016 3:55 am

Helder wrote:You attach the battery to those then from those you go to the power supply board. You can use anything over 10k pot but the tweaking of it will be more sensitive as the range in the pot value is much greater so a small turn will cover a larger range of values than on the 10k pot.
Thanks for the reply. By 'those those' I assumed you meant the legs of the pot so I attached the positive and negative to those, powered it up, and turned the 50k pot i was using but the led didnt illuminate at all. Then not really thinking, in frustration, I attached the power to the other legs of the pot and after turning it up the magic smoke appeared and bursting into flames like a nice firework display. It also fried the only spare 33k resistor I had so I guess it's game over now. :lol: I really don't get what's wrong with my circuit. Just wish I learnt electronics when I was younger, just can't grasp it nowadays.

User avatar
Helder
Trailblazer
Trailblazer
Posts: 2749
Joined: Thu May 05, 2016 8:33 am
Location: Fall River, MA
Has thanked: 1402 times
Been thanked: 3069 times

Re: Low Battery LED Indicator Board [OSHPark]

Post by Helder » Sat Sep 10, 2016 11:04 am

Zero wrote:
Helder wrote:You attach the battery to those then from those you go to the power supply board. You can use anything over 10k pot but the tweaking of it will be more sensitive as the range in the pot value is much greater so a small turn will cover a larger range of values than on the 10k pot.
Thanks for the reply. By 'those those' I assumed you meant the legs of the pot so I attached the positive and negative to those, powered it up, and turned the 50k pot i was using but the led didnt illuminate at all. Then not really thinking, in frustration, I attached the power to the other legs of the pot and after turning it up the magic smoke appeared and bursting into flames like a nice firework display. It also fried the only spare 33k resistor I had so I guess it's game over now. :lol: I really don't get what's wrong with my circuit. Just wish I learnt electronics when I was younger, just can't grasp it nowadays.
To those I meant the Positive and Negative solder hole on the board. You attach your battery to those and from those you attach it to the power supply battery input.
My Sale Threads:

Retro PSU, 3.5A output!


Chat with me and other members


Don't contact me about obtaining my board files (as you will not get them). Don't contact me about any of my boards if they are sold out, they will be restocked as soon as I can get them.


Don't support thieves like ckliang who copied my AIO to resell and is now cloning the mintyPi, support the original creators and not the thieves!

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest