Cigarette lighter charger

[flyingcheesehead]

Hey folks,

I'm looking for something that I can't find: A cigarette lighter charger that has all of the following:

1) Dual 2.1 amp USB ports, like this one
2) Flush-mount or very close to it - IE, when it's in the socket, the USB ports aren't sticking out, like this one. The current one I have sticks out and in the Mooney the plug is behind the yoke, so to avoid putting stress on the USB cables I have to plug it in shortly after takeoff.
3) Works correctly with both 12/14V and 24/28V systems, like this one.

Anyone know of such a thing, or is it still unobtanium?

(EDIT: Answer below.)

 

[Steve]

I came across the following looking for a similar item not too long ago:

1) Many, if not all, plug-in DC chargers with dual USB output ports will accept 12v and 24v input for a 5.2v output. You have to look at the rating on the unit itself, not the packaging, to be sure.

2) Dual port DC USB chargers are usually 2.1A and 1.0A outputs and even if they are both "rated" at 2.1A each they cannot deliver it simultaneously to both ports.

I ended up getting an external battery similar to this for independence of power supply:

http://www.ianker.com/product/79AN7904-BA

 

[flyingcheesehead]

1) Many, if not all, plug-in DC chargers with dual USB output ports will accept 12v and 24v input for a 5.2v output. You have to look at the rating on the unit itself, not the packaging, to be sure.

It's definitely not all - I once charged my iPhone on a 24V outlet without thinking about it, and it was very unhappy battery-wise for a few days. Luckily, it returned to normal. Wish I'd measured the output, but I didn't have the tools with me at the time.

2) Dual port DC USB chargers are usually 2.1A and 1.0A outputs and even if they are both "rated" at 2.1A each they cannot deliver it simultaneously to both ports.

That's actually OK with me - I don't expect to have both devices drained at the same time in normal use.

I ended up getting an external battery similar to this for independence of power supply:

http://www.ianker.com/product/79AN7904-BA

That's a cool product, and an interesting solution. However, that would preclude using one feature I'd like to on the Stratus: Turn On When Powered. That way, it'd turn itself on and off with the Master switch, instead of letting me forget to turn it off for the umpteenth time and draining the battery.

 

[John221us]

http://www.amazon.com/iFlash-Lighte...9114709&sr=8-2&keywords=cigarette+usb+adapter

 

[flyingcheesehead]

http://www.amazon.com/iFlash-Lighte...9114709&sr=8-2&keywords=cigarette+usb+adapter

Good try, but only rated for 12-18VDC input, and only one 2-amp output.

I've found a ton of these things that meet *some* of my needs, but none that meet 'em all yet.

 

[Sam D]

In this day and age, can't you just send these specs to somewhere across the pacific and next week, your new product line is available and already bubble wrapped for you?

I'll be one of your first customers...

 

[John221us]

Good try, but only rated for 12-18VDC input, and only one 2-amp output.

I've found a ton of these things that meet *some* of my needs, but none that meet 'em all yet.

It says 12 to 24 in the specs and yes, I realize it only has one two amp output, but you mentioned that might work.

DC Input Voltage: 12 VDC to 24 VDC
Output Voltage: 4.75 VDC min 5.25 VDC max
Output Current: 0A min 3A max
Over-Current Protection: 4.5A
Short-Circuit Protection
Overheating Protection
Operating Temp: 0 ~40 deg C

 

[flyingcheesehead]

It says 12 to 24 in the specs and yes, I realize it only has one two amp output, but you mentioned that might work.

DC Input Voltage: 12 VDC to 24 VDC
Output Voltage: 4.75 VDC min 5.25 VDC max
Output Current: 0A min 3A max
Over-Current Protection: 4.5A
Short-Circuit Protection
Overheating Protection
Operating Temp: 0 ~40 deg C

Where'd you find those specs? The specs at the link you posted said 12-18VDC.

 

[Steve]

It's definitely not all - I once charged my iPhone on a 24V outlet without thinking about it, and it was very unhappy battery-wise for a few days. Luckily, it returned to normal. Wish I'd measured the output, but I didn't have the tools with me at the time.

Was that a dual port charger?

Anyway, this might work if you don't need both ports at 2.1A:

http://www.tmart.com/Mini-Dual-USB-Port-Car-Charger-for-iPhone-iPad-iPod-White_p132011.html

or

http://www.tmart.com/Mini-Dual-USB-Port-Car-Charger-for-iPhone-iPad-iPod-Black_p132012.html


.

 

[mcmanigle]

This looks promising: http://thewirecutter.com/reviews/best-usb-car-charger/

(And the website overall is an interesting idea; I hadn't run across it before.)

But the specs list 10 - 16 v in, so might not work on 24 v systems...

 

[jhausch]

Kent, what's your degree in?

oke:


Edit to add/ask: If the plug stuck out a little bit and the USB ports exited at a right angle, would that fit? That might give you a little more real estate to work with on the PCB

 

[Capt. Geoffrey Thorpe]

So, put a 12V regulator behind the cigarette lighter (and don't try to use the lighter itself again).

 

[Shepherd]

I bought the flushmount, and replaced the voltage regulator inside it. It will handle up to 28 volts now.

 

[flyingcheesehead]

This looks promising: http://thewirecutter.com/reviews/best-usb-car-charger/

(And the website overall is an interesting idea; I hadn't run across it before.)

But the specs list 10 - 16 v in, so might not work on 24 v systems...

Yeah, that ReVolt one is exactly what I want except for the 24-28V part - And I talked with Scosche about it, they specifically said it's no good for the higher voltage systems.

 

[flyingcheesehead]

Kent, what's your degree in?

Yeah, I am kinda tempted to do something about it... But OTOH, it's quite possible that better minds than mine have already decided that what I want isn't possible with a flush mount due to high current / heat dissipation requirements.

Edit to add/ask: If the plug stuck out a little bit and the USB ports exited at a right angle, would that fit? That might give you a little more real estate to work with on the PCB

Yep, that'd work. The problem is that if I leave it in on the ground, the yoke is RIGHT THERE at the back of the USB cables and puts a lot of strain on them.

 

[flyingcheesehead]

I bought the flushmount, and replaced the voltage regulator inside it. It will handle up to 28 volts now.

Which one did you buy, what parts did you need to get for it, and how difficult was the conversion? Does the output still meet the same specs? Thanks!

 

[Shepherd]

Which one did you buy, what parts did you need to get for it, and how difficult was the conversion? Does the output still meet the same specs? Thanks!

Similar to the one you link to.
I used a 7824 24vdc 1 Amp chip, (I use the metal ground connector on the adaptor as the heat sink) and a couple of 2 amp, 5 volt zener diodes, one for each side. Because I am stepping down to 5 volts I can draw more than enough amps.
I don't remember if I had to change any of the resistors, It's been a couple of years, and I either didn't bother to diagram it or didn't file it somewhere for future reference. If I find the diagram I'll post it here.
I do remember having to do some judicious grinding to fit everything in the plug.

 

[flyingcheesehead]

Similar to the one you link to.
I used a 7824 24vdc 1 Amp chip, (I use the metal ground connector on the adaptor as the heat sink) and a couple of 2 amp, 5 volt zener diodes, one for each side. Because I am stepping down to 5 volts I can draw more than enough amps.
I don't remember if I had to change any of the resistors, It's been a couple of years, and I either didn't bother to diagram it or didn't file it somewhere for future reference. If I find the diagram I'll post it here.
I do remember having to do some judicious grinding to fit everything in the plug.

So, presumably some soldering was involved?

I was also figuring that anything with a small enough plug (ie flush mount) would be difficult to "edit".

 

[flyingcheesehead]

Hmmm. I think I may just have to use one of my dual 2.1 amp adapters and a couple of these:

http://www.amazon.com/HDE-Right-Angle-Female-Cable/dp/B006C0PNJK/ref=pd_sim_pc_1

 

[Shepherd]

So, presumably some soldering was involved?

I was also figuring that anything with a small enough plug (ie flush mount) would be difficult to "edit".

In the interests of full disclosure, I ruined one before I got one working.

 

[flyingcheesehead]

Hey folks,

I'm looking for something that I can't find: A cigarette lighter charger that has all of the following:

1) Dual 2.1 amp USB ports, like this one
2) Flush-mount or very close to it - IE, when it's in the socket, the USB ports aren't sticking out, like this one. The current one I have sticks out and in the Mooney the plug is behind the yoke, so to avoid putting stress on the USB cables I have to plug it in shortly after takeoff.
3) Works correctly with both 12/14V and 24/28V systems, like this one.

Anyone know of such a thing, or is it still unobtanium?

They finally have one, it appears:

http://www.amazon.com/Scosche-USBC202M-Charger-works-iPhone/dp/B0077PM3KG/ref=pd_cp_e_3

 

[SkyHog]

Hey folks,

I'm looking for something that I can't find: A cigarette lighter charger that has all of the following:

1) Dual 2.1 amp USB ports, like this one
2) Flush-mount or very close to it - IE, when it's in the socket, the USB ports aren't sticking out, like this one. The current one I have sticks out and in the Mooney the plug is behind the yoke, so to avoid putting stress on the USB cables I have to plug it in shortly after takeoff.
3) Works correctly with both 12/14V and 24/28V systems, like this one.

Anyone know of such a thing, or is it still unobtanium?

Kent - I have one sitting around that I used to use in my F150. Its yours if you want it.

 

[flyingron]

Hmmm. I think I may just have to use one of my dual 2.1 amp adapters and a couple of these:

Such a cord while potentially useful is, in fact, a violation of the USB spec.

 

[flyingcheesehead]

Kent - I have one sitting around that I used to use in my F150. Its yours if you want it.

Thanks Nick... But I already ordered one of the ones I linked to. Save yours for when you own an airplane.

Such a cord while potentially useful is, in fact, a violation of the USB spec.

The 90-degree cord is? Why?

 

[zaitcev]

The 90-degree cord is? Why?

While strictly speaking correct, you may disregard Ron's message in practice. Just think: does it matter if something is out of spec if it works? It's the premise of the whole Experimental Amateur-Built segment!

The USB spec prohibits A-A extenders for the reason that its authors intend reliability: no matter what cables you buy, as long as you do not chain more than 4 hubs (including the root hub, IIRC), the whole bus will continue to operate. To accomplish that, the cable spec is done so it can be violated and the whole system still functional.

To be specific, timing of the bus is such that a single bus cannot be larger than about 12.5 m in radius - but only if cables are made from infinitely thick silver, which is obviously impractical. As you make cables thinner, their resistance increases, signals become weaker, and at certain point they drown in noise. The retiming circuit in hub allows them to continue, up to the full 12.5 m. Now, if you divide that by 4, you get the maximum legal length of the cable which can be safely mixed and matched. If someone chains 3 external hubs, then inserts the "illegal" A-A extender anywhere, the system goes out of spec. However, if you do NOT have a hub, and your A-B cable is thick enough, the A-A extender works just fine. That is why people buy those at Amazon: because they work.

The angle of the cable has nothing with it, or at least I do not remember a prohibition on it. There's an funny recommendation to have a tacitly recognizable logo on one side. It works in conjunction with recommendation to orient sockets (when practical). This way you can plug cables behind system blocks by touch. Of course Apple famously blows off the relief logo and there's absolutely nothing USB Forum can do about it.

 

[Steve Job]

FWIW, the new iPads need a 2.4 amp charger. We found this out 2 weeks ago during our long trip to Florida, watching the iPad mini retina slowing discharge using a 2.1 amp charger. One of the vendors at Sun N Fun (mypilotstore?) said the problem was the low capacity charger, so we bought the 2.4 amp model. No issues on the 9.9 hour trip back home.

 

[jpflys]

This will power my I pad for 2 days

 

[kevmor99]

FWIW, the new iPads need a 2.4 amp charger. We found this out 2 weeks ago during our long trip to Florida, watching the iPad mini retina slowing discharge using a 2.1 amp charger. One of the vendors at Sun N Fun (mypilotstore?) said the problem was the low capacity charger, so we bought the 2.4 amp model. No issues on the 9.9 hour trip back home.

Which model is that? I got one USB cigarette charger stating it would charge an iPad, it shows it charging but the percentage goes down...

 

[Steve Job]

Which model is that? I got one USB cigarette charger stating it would charge an iPad, it shows it charging but the percentage goes down...

I'm pretty sure it was this one:

http://www.mygoflight.com/dualmicro/

I see that it is available from several sources, including Amazon. We are also using the mygoflight mini sport case (ram mounted). Pricey, but quality stuff.

 

[flyingcheesehead]

While strictly speaking correct, you may disregard Ron's message in practice. Just think: does it matter if something is out of spec if it works? It's the premise of the whole Experimental Amateur-Built segment!

Yeah, I'm not gonna have any hubs in the plane.

The USB spec prohibits A-A extenders for the reason that its authors intend reliability: no matter what cables you buy, as long as you do not chain more than 4 hubs (including the root hub, IIRC), the whole bus will continue to operate. To accomplish that, the cable spec is done so it can be violated and the whole system still functional.

To be specific, timing of the bus is such that a single bus cannot be larger than about 12.5 m in radius - but only if cables are made from infinitely thick silver, which is obviously impractical. As you make cables thinner, their resistance increases, signals become weaker, and at certain point they drown in noise. The retiming circuit in hub allows them to continue, up to the full 12.5 m. Now, if you divide that by 4, you get the maximum legal length of the cable which can be safely mixed and matched. If someone chains 3 external hubs, then inserts the "illegal" A-A extender anywhere, the system goes out of spec. However, if you do NOT have a hub, and your A-B cable is thick enough, the A-A extender works just fine. That is why people buy those at Amazon: because they work.

Ah. I was thinking maybe it had something to do with losses in the connectors. So there must be a 3m max on individual cable length too then?

 

[zaitcev]

Ah. I was thinking maybe it had something to do with losses in the connectors. So there must be a 3m max on individual cable length too then?

Actually... I looked it up, and although superceded by spec 3.1, the 2.0 said:

6.4.1
• The maximum allowable cable length is determined by signal pair attenuation and propagation delay. Refer to Sections 7.1.14 and 7.1.17 for details.
• Differences in propagation delay between the two signal conductors must be minimized. Refer to Section 7.1.3 for details.

7.1.14
The total delay through the upstream cable and hub electronics must be a maximum of 70 ns (THDD1). If the hub has a detachable USB cable, then the delay (THDD2) through hub electronics and the associated transmission line must be a maximum of 44 ns to allow for a maximum cable delay of 26 ns (TFSCBL).

If cables were isolated with vacuum, their maximum length would be about 8m. However, the PVC isolation slows signals down by about 30%, I think. That makes for the longest detacheable cable of about 5.5m or 16 ft. This seems longer than I recall from the past. I seem to remember that a regular cable is limited to about 3m in length, so I must be missing something in my calculations.

 

[greghughes]

I use this one, fits flush and delivers dual 2.1 amps:

http://www.amazon.com/gp/product/B0077PM3KG

and the manufacturer also has a slightly higher powered model:

http://www.scosche.com/chargers/ipad-usb-car-charger-two-port

I've seen specs for these that say 10-16VDC, 12-24 VDC and 12-28VDC. I use them in my 14V airplane, have not tried in a 28V plane.

 

[flyingron]

Just watch the aggregate length. Frankly, if you're only using it to get the 5V out of it, it's not going to be an issue really. The data reliability is the reason such things are banned. But it's not like the USB police are coming after you...

 

[Clark1961]

They finally have one, it appears:

http://www.amazon.com/Scosche-USBC202M-Charger-works-iPhone/dp/B0077PM3KG/ref=pd_cp_e_3

These are dual 2.4 amp chargers...at least the two I got said they are

 

[flyingcheesehead]

These are dual 2.4 amp chargers...at least the two I got said they are

Mine said 10-16V but it appears to work OK anyway on the airplane's 28V system.

 

[weirdjim]

Mine said 10-16V but it appears to work OK anyway on the airplane's 28V system.

And you do keep a fully charged fire extinguisher on board I hope.

Jim

 

[GeorgeC]

Just ordered an Anker dual-voltage, dual-port 2.4A charger. Not flush mount, but cheaper than the scosche.

edit: First one was DOA, but their customer support made it right. I like this device.

 

[SylphenSky]

Hi folks, as an effort to keep my Stratus and iPads charged on long cross countries, I was in search for a dual 2.1amp 24 volt car charger. I purchased one from Sportys, that is no longer available but stated 24v on the device. I used it for a couple of hours but while flying this weekend, the thing blew up and caught fire in the cockpit. Luckily nothing was close enough to catch on fire, like clothing or paper in the side pocket. I pulled it out by the usb wires and the thing extinguished itself, but having searched a long time for one of these things I am hesitant to use another one. Lucky it was a rather bulky one that had a fuse that short circuited, I am not so sure that many advertised have the fuse protection. But it is a concern that many pilots are flying with a lot of stuff that may need to be plugged in and this is a real safety issue! Question is, should I have the 24v lighter rewired with a voltage converter so I can use a 12v adapter or is there really a safe 24v dual charger around. I have purchased several advertised as 12/24v only to have them arrive as 12/16-18v if that.

 

[flyingcheesehead]

Hi folks, as an effort to keep my Stratus and iPads charged on long cross countries, I was in search for a dual 2.1amp 24 volt car charger. I purchased one from Sportys, that is no longer available but stated 24v on the device. I used it for a couple of hours but while flying this weekend, the thing blew up and caught fire in the cockpit. Luckily nothing was close enough to catch on fire, like clothing or paper in the side pocket. I pulled it out by the usb wires and the thing extinguished itself, but having searched a long time for one of these things I am hesitant to use another one. Lucky it was a rather bulky one that had a fuse that short circuited, I am not so sure that many advertised have the fuse protection. But it is a concern that many pilots are flying with a lot of stuff that may need to be plugged in and this is a real safety issue! Question is, should I have the 24v lighter rewired with a voltage converter so I can use a 12v adapter or is there really a safe 24v dual charger around. I have purchased several advertised as 12/24v only to have them arrive as 12/16-18v if that.

Hi Susan,

Welcome to PoA!

The Sportys-branded chargers were recalled a while back - I would call Sporty's and tell them what happened, they will likely send you something new for free. In fact, they sent me 2.1/1.0 amp replacements to start, and when I complained that it wasn't dual 2.1, they sent me one of those after confirming that it was OK with me (There was something odd about the specs, I forget the details). All of the replacements were Scosche brand and have worked quite well, where I had problems with both of the Sporty's ones that I had.

Step 2: If you're still worried about this, buy one of the Anker battery units mentioned above. They're purpose-built, and the 10,000 mAh ones are good for 5+ complete charges of the iPad, or probably 40+ hours of use between charges.

Hope this helps, and welcome aboard once again!

 

[MSPAviator]

This is what I use. For $2.06 including shipping, it is almost free.

Fits pretty flush.


http://www.fasttech.com/products/1154/10000315/1035501