I have an Arduino Uno which is powering an Adafruit TLC5947 24-channel PWM LED driver (Which is in turn powering 12 bi-colour LEDs)
I have to be able to power this at full power (so all LEDs at maximum brightness) for 12 hours and it is to be constructed as a self contained unit so things can't be too big. (Think a standard size house brick .. very rough estimate but couldn't think of anything else that's easily recognisable!)
I am looking into ways to battery power this .. and the two options I have come across so far are either:
1 - use a battery pack (although these tend to be quite large)
2 - use a load of AA batteries in a series/parallel configuration to give me the required power.
It would preferably need to be rechargeable so if I went down the route of the series/parallel configuration I would need to include a small charging circuit with it, but the battery pack can just be disconnected and plugged in.
So, ideally I would like to go for a battery pack - simplicity is key so it just makes sense. However I am not having much luck finding a suitable pack .. I may just be looking in the wrong place, I have never looked for these before.
I believe I need 8640mA for the 12 hours. Each LED has a maximum forward current of 30mA (and forward voltages of 3.0-3.8V / 1.7-2.3V, bi-colour so two different colours)
So we have 30mA * 24 + the 25mA for the Arduino itself, all multiplied by 12, giving us 8640mA. This is obviously the extreme maximum and is unlikely to be needed but it *could* be used so I need to assume it will be!
When looking into this previously it came up that you should look for a battery around 3 times larger than what you require (I assume this is because of voltage/current drops etc) so I need to look for something around 26AH?
Is this all correct? Also if you know of any good battery packs etc that would be great, thanks!
I have to be able to power this at full power (so all LEDs at maximum brightness) for 12 hours and it is to be constructed as a self contained unit so things can't be too big. (Think a standard size house brick .. very rough estimate but couldn't think of anything else that's easily recognisable!)
I am looking into ways to battery power this .. and the two options I have come across so far are either:
1 - use a battery pack (although these tend to be quite large)
2 - use a load of AA batteries in a series/parallel configuration to give me the required power.
It would preferably need to be rechargeable so if I went down the route of the series/parallel configuration I would need to include a small charging circuit with it, but the battery pack can just be disconnected and plugged in.
So, ideally I would like to go for a battery pack - simplicity is key so it just makes sense. However I am not having much luck finding a suitable pack .. I may just be looking in the wrong place, I have never looked for these before.
I believe I need 8640mA for the 12 hours. Each LED has a maximum forward current of 30mA (and forward voltages of 3.0-3.8V / 1.7-2.3V, bi-colour so two different colours)
So we have 30mA * 24 + the 25mA for the Arduino itself, all multiplied by 12, giving us 8640mA. This is obviously the extreme maximum and is unlikely to be needed but it *could* be used so I need to assume it will be!
When looking into this previously it came up that you should look for a battery around 3 times larger than what you require (I assume this is because of voltage/current drops etc) so I need to look for something around 26AH?
Is this all correct? Also if you know of any good battery packs etc that would be great, thanks!