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Re: Low Battery LED Indicator Board [OSHPark]

Posted: Fri Jul 29, 2016 1:14 pm
by kitsch-bent
Ganreizu wrote:
Helder wrote:That's a bit pricey and not sure what the IC draws but I know this circuit (the boards in first post) draws 1.5mA to function and go as low as 1.4v for the threshold sensor but obviously we don't need that as that is way too low.
Yeah i'm not sure if batt_dmg is appropriate for GBZ build. Just kind of bought it for the hell of it so if it worked great if not oh well. Looking like it won't work at all since it's connected to the original circuitry and is based on the batteries it's supposed to run from. Got this quote from the installation doc:
if you replace the LED with your own, assume the forward voltage to be 4.6V @ 20mA (the IC will not connect the circuit until engaged at 4.6V). use this for your calculations. the resistor is 0603 package. the included red LED is rated at 2.5V @ 20mA
the light will illuminate when the batteries can only supply 4.6V. the DMG is designed to run at 5V, with a voltage input tolerance of +/- 10%. meaning, (some of) these ICs are suggested to operate at 4.5V – 5.5V. this low-power indicator will alert you when the batteries can only supply 4.6V, so that you may extend the life of your equipment and are not surprised by a weak battery when it matters most (like a performance)
correct, its made for the original DMG application. based off the specs for the DMG's power regulator board, and utilizes power switch cover (which it illuminates). those power considerations do not apply here really. its for the original DMG Game Boy, as-is, not the GBZ application which apart from the shape is much, much different internally.

:)

nice project!

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Fri Jul 29, 2016 1:49 pm
by Helder
On a side note @kitsch-bent I was in talks of doing something like your board some time ago with one of your competitors and it was geared towards the original DMG too and used the original LED place holder for the new LED that switched colors to indicate low battery. I never got to take it beyond the bread board for a few reasons but mainly time and lack of interest.


And back on topic.

Yes the board I have is adjustable to whatever voltage you set it at while @kitsch-bent's board is for the original DMG with a different battery voltage drop out (I had all this info at one time saved but eh) since it uses the AA alkaline (recharables too).

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Sat Jul 30, 2016 6:16 am
by username 123
Fantastic work Helder. Could you please also put up links for the needed smd parts as well?

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Sat Jul 30, 2016 7:39 am
by Helder
username 123 wrote:Fantastic work Helder. Could you please also put up links for the needed smd parts as well?
All set, it's on the first post.

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Tue Aug 02, 2016 2:53 am
by Megavolt
Really nice work here !

Is it possible to upload the connection diagramm oder maybe just a sketch of it ? Would be really helpful ! :)

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Tue Aug 02, 2016 5:08 am
by Helder
Megavolt wrote:Really nice work here !

Is it possible to upload the connection diagramm oder maybe just a sketch of it ? Would be really helpful ! :)
Are you asking how to wire it? It's simple the battery connects to this and from this board it goes to the power supply input.

Battery > This Board > Power Supply

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Wed Aug 03, 2016 10:11 am
by Megavolt
I meant the connections between the electric components, like resistors, led's and transistors.

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Wed Aug 03, 2016 3:28 pm
by Helder
Megavolt wrote:I meant the connections between the electric components, like resistors, led's and transistors.
You mean the schematic, here it is:

Image

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Wed Aug 10, 2016 2:57 am
by Camble
@Helder I've been playing around with the values in simulation and these resistor values are definitely too high for a 3.7v battery. The 10K resistor won't allow the LED to light at all. Better to replace this with a 56R or something nice and low. Swapping the 33K resistors for 10K or thereabouts and about half the value for the potentiometer should do the trick.

I've been trying to get some fixed values to eliminate the potentiometer, but it's a bit more difficult without testing in the real world.

Re: Low Battery LED Indicator Board [OSHPark]

Posted: Wed Aug 10, 2016 5:54 am
by Helder
I should have the physical boards in today so I will test the proper values and post here.