A standard 12 volt D.C power supply usually runs ~13.7 volts. The battery I suggested above has charge protection built in..
I bought a handful of these to charge from my home battery. The voltage is regulated to 12.6 volts, the same as the provided factory chargers..
10pcs NEW Mini 360 4 75V 23V to 1V 17V DC DC Buck Converter Step Down Module | eBay
I bought a handful of these to charge from my home battery. The voltage is regulated to 12.6 volts, the same as the provided factory chargers..
10pcs NEW Mini 360 4 75V 23V to 1V 17V DC DC Buck Converter Step Down Module | eBay
Ok. So you're saying that the built-in protection negated the need for a smart charger in your case and they can just be charged from a normal power supply, or in your case, your home battery?
I did look at some of these batteries with the on/off switch and dual leads, but for some reason I was weary of the quality of them. Probably irrationally so!
Those little boards I suggested have an adjustable output from 1 to 17 volts. The input can be at least a volt above your desired voltage up to 23 volts. My home battery can go as high as 14.2 volts during the day, which is a little high for those batteries. I regulate to 12.6 volts. This level is the same as the output of the chargers that come with the batteries..
You could use any power supply between 13-23 volts D.C. with that little board and adjust to 12.6 volts to charge with. The batteries have charge protection built in. I use them all of the time for my portable stuff..
You could use any power supply between 13-23 volts D.C. with that little board and adjust to 12.6 volts to charge with. The batteries have charge protection built in. I use them all of the time for my portable stuff..
Ok, I see two or three ways I can wire this with a LI battery.
1) Battery power is the only thing connected to the modules. It'll either charge/float when plugged in and the unit is off or and switch to battery power only when switched on, unplugged or not.
2) Connect the battery ground to the disconnect pin on the female dc jack and wire it so that when it's plugged in and switched on it runs from the PS. Unplugged and switched on it uses battery. plugged in and switched off it charges.
3) Wire power supply, battery and components in parallel and trust the batteries protections to do their thing. This is assuming that the batteries can charge on a normal power supply.
Thoughts?
1) Battery power is the only thing connected to the modules. It'll either charge/float when plugged in and the unit is off or and switch to battery power only when switched on, unplugged or not.
2) Connect the battery ground to the disconnect pin on the female dc jack and wire it so that when it's plugged in and switched on it runs from the PS. Unplugged and switched on it uses battery. plugged in and switched off it charges.
3) Wire power supply, battery and components in parallel and trust the batteries protections to do their thing. This is assuming that the batteries can charge on a normal power supply.
Thoughts?
Thanks. So with a 12v regulated power supply I wouldn't need a step down regulator correct? You just need it because of your battery to battery charging scheme?
Scratch this one. I think the disconnect only works with a separate charging setup so I would need two power supplies/chargers and two dc jacks. too bad because this seems like the best option
That's what the little board is for. Connect your source power supply (12 volt regulated) and adjust the output of the board to 12.6 volts. Connect to the battery and WALA! Real simple..
Most all 12 volt regulated supplies run ~13.7 volts. That's a tad too high to charge the LiPo's safely. The chargers that were supplied with the batteries I purchased has an output of 12.6 volts @ 500 mA. I have no A.C. voltage source in my house so I had to connect to my battery.. (My home is totally a 12 V.D.C. system)
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Icr 18650 Li-ion Battery Packs 3s1p 11.1v 2200mah With Protection - Buy 18650 Li-ion Battery Packs 3s1p 11.1v 2200mah With Protection,Icr 18650 Battery Pack,11.1v Li-ion Battery Product on Alibaba.com This battery for instance has built-in protection and balance, yet they recommend their smart LI charger and say never to use a regular dc power supply.
Is the power supply warning just because it needs a step down regulator?
And why would it need a smart charger if the battery's already smart?
Is the power supply warning just because it needs a step down regulator?
And why would it need a smart charger if the battery's already smart?
Ok. I expected a bit longer run time than that. Sounds like I'd only get a few hours from a single battery. And with the unit only able to run from the battery that would probably get annoying
just build the thing and measure the current drain from the cells you already have. That way you can get a better idea on packaging and real world use in your house.
Re> Li-ion can be left on standby, the closer to nominal V , the better for life time, closer toward max V for more time off charge. Decide based on your use and batt. replacement expectation. Probably 4.0 V per cell is a good tradeoff. so a power source of 12.0Vdc at 1.0 Amps can be left on and recharge all 3 cells in 1 to 2 hours. the power source should be regulated with current limit!
The ideal is if you can search out a protection circuit ( programmed cut off ) already designed for 3 series cells then you can use unprotected cells.
once you know the current drain and have a circuit that cuts off the power when discharged, then you can shop for cells. Battery test-review 18650 individual tests
I just bought some Sanyo UR18650ZY based on my lower current usage and cutoff voltage they actually hold up better than the latest and greatest IMR Panasonic cells. looking at the review test data. I paid just over 7 bucks shipped for 2 cells. I use a external charger to charge each cell off the device, so no worries about balance.
Re> Li-ion can be left on standby, the closer to nominal V , the better for life time, closer toward max V for more time off charge. Decide based on your use and batt. replacement expectation. Probably 4.0 V per cell is a good tradeoff. so a power source of 12.0Vdc at 1.0 Amps can be left on and recharge all 3 cells in 1 to 2 hours. the power source should be regulated with current limit!
The ideal is if you can search out a protection circuit ( programmed cut off ) already designed for 3 series cells then you can use unprotected cells.
once you know the current drain and have a circuit that cuts off the power when discharged, then you can shop for cells. Battery test-review 18650 individual tests
I just bought some Sanyo UR18650ZY based on my lower current usage and cutoff voltage they actually hold up better than the latest and greatest IMR Panasonic cells. looking at the review test data. I paid just over 7 bucks shipped for 2 cells. I use a external charger to charge each cell off the device, so no worries about balance.
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your batteries maybe not as good as the seller says, test the batteries real mAH
they look dodgy just by the specs, you broke my 1st rule of batteries, buy authentic OEM cells, you know with traceable specs and real data sheets. not vendor rewraps and marketing claims
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i ran a small cklass AB amp on 3x6V series sla batterys, was left over from an alarm system. had to drop the voltage with (i think ) 2 series diodes, and it kept on going for days with no issues. probably a class D amp can run for a lot more time on a similar setup. the charger i used was made for a cordless drill. some junk i found, literally.
I will do that once the BT boards arrive. One of the BT boards is also and integrated amp, so at this point I can't measure draw from anything other than the small amp module that I have now. And the led.
That's why I asked for a ballpark, but I won't be ordering any batteries until I get all the components in my possession. The rest of it should be here any day, I think. This is the first time I've ordered anything from china so....we shall see.
Thanks for all the other good info! That's exactly what I need
I have an unrelated, but related question that I'll go ahead and post here since it's the correct forum.
I bought a few of these to play around and it's what I've been using with these battery experiments. Power Supply Audio Amplifier Board Module TDA2030 TDA2030A 6 12V 18W Single | eBay
I also have a bit larger amp/bt module on the way that I may use instead. Anyways, I'm wondering if the small cap next to the speaker output terminal is acting as a high pass filter for the output signal. It's 470uF 16v. I'm guessing it's a dc blocking cap, but I really don't know anything about chip amps. It looks like it may be in parallel with a diode.
When I measure my speakers they fall of a cliff at about 90Hz and have a measured f3 of around 95. Doesn't matter if they're raised up 4ft off the ground or measured while sitting on a table. The sims I did before buying the drivers and building the enclosure show an f3 of close to 70Hz and I'd expect some kind of gain when they're sitting on a flat surface.
With 4 ohm speakers, if I'm not mistaken, 470uF would make a highpass with a corner frequency of about 85Hz, so pretty close to what I'm seeing. If this is acting as a highpass, is there any harm in trying a 1000uF 16v cap in it's place? This should give a corner frequency of around 40Hz. I have a number of other larger and smaller value caps on hand too.
Any help's appreciated
I bought a few of these to play around and it's what I've been using with these battery experiments. Power Supply Audio Amplifier Board Module TDA2030 TDA2030A 6 12V 18W Single | eBay
I also have a bit larger amp/bt module on the way that I may use instead. Anyways, I'm wondering if the small cap next to the speaker output terminal is acting as a high pass filter for the output signal. It's 470uF 16v. I'm guessing it's a dc blocking cap, but I really don't know anything about chip amps. It looks like it may be in parallel with a diode.
When I measure my speakers they fall of a cliff at about 90Hz and have a measured f3 of around 95. Doesn't matter if they're raised up 4ft off the ground or measured while sitting on a table. The sims I did before buying the drivers and building the enclosure show an f3 of close to 70Hz and I'd expect some kind of gain when they're sitting on a flat surface.
With 4 ohm speakers, if I'm not mistaken, 470uF would make a highpass with a corner frequency of about 85Hz, so pretty close to what I'm seeing. If this is acting as a highpass, is there any harm in trying a 1000uF 16v cap in it's place? This should give a corner frequency of around 40Hz. I have a number of other larger and smaller value caps on hand too.
Any help's appreciated
yes since its a single supply there is a DC block in the output.
your speaker will infact have a raised impedance near the box frequency, so sometimes folks use a highish cap in series to produce changed bass Q. try it both ways and hear. In contrary to "normal logic", you may get less bass depending on the box tuning. BTW a diode in parallel is certainly troubling please trace it out closer using the device data sheet.
also your driver may have a higher Fs out of the box than advertised, which is common.
your speaker will infact have a raised impedance near the box frequency, so sometimes folks use a highish cap in series to produce changed bass Q. try it both ways and hear. In contrary to "normal logic", you may get less bass depending on the box tuning. BTW a diode in parallel is certainly troubling please trace it out closer using the device data sheet.
also your driver may have a higher Fs out of the box than advertised, which is common.
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The diode doesn't appear to be in parallel using the tda2030a data sheet and recommended circuits. I only guessed that it may be in parallel with the cap because you can't actually see the traces on the board.
Fb is 75Hz for my box with a bit of port damping. So smaller impedance below tuning, around 3.5 ohms at fb and a higher peak above. I did play with a large cap for a 1st order high pass when I modeled the crossover, but I tuned the box for a couple db peak in the response above tuning so I didn't want to add anymore peaking with a highpass. Otherwise, I'd have to tune the box lower to counter act this and the port gets too long.
So would a high pass on the amp output cause this same type of peaking above fc? If so, I've been thinking that it has maybe too much output between 100-200Hz and maybe this is the reason why.
When you say try it both ways, are you talking about changing the output cap on the board or adding a large cap before the xo? Or is it really the exact same thing?
Fb is 75Hz for my box with a bit of port damping. So smaller impedance below tuning, around 3.5 ohms at fb and a higher peak above. I did play with a large cap for a 1st order high pass when I modeled the crossover, but I tuned the box for a couple db peak in the response above tuning so I didn't want to add anymore peaking with a highpass. Otherwise, I'd have to tune the box lower to counter act this and the port gets too long.
So would a high pass on the amp output cause this same type of peaking above fc? If so, I've been thinking that it has maybe too much output between 100-200Hz and maybe this is the reason why.
When you say try it both ways, are you talking about changing the output cap on the board or adding a large cap before the xo? Or is it really the exact same thing?
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