# Sanyo NC-MDU01 AA AAA USB Charger



## koala (May 21, 2007)

All right I got it this morning, sorry dont have a camera with me have use the scanner. It's pretty sweet little charger. It charges cells pretty well, warms up the cell slightly, haven't been able to test it throughly. The springs are soft. Some cells can be slightly loose in the slots but still maintain contact. I like it because it doesn't dent the cells. However it may cause connection problems. The AA-AAA contact mechanism is quite clever and it works well. The USB cable is too short for desktop use but it is right at home with a laptop.

It's quite interesting to see a little ferrite bead right next to the diode D1. It looks like they done their EMI testing properly. The circuit board is single layer single sided. The microcontroller is a 8-bit 20MHz Atmel Tiny461 with 4 channel 10-bit ADC. It's nice to see this is a software based charger. 10-bit ADC should have enough resolution to do a proper -mV delta end of charge detection. The AVR Tiny461 has a maximum operating voltage of 6.0V and it is wired directly to the USB port despite a SMD 1A fuse. Any more than that means :sick2:.

There is a massive row of resistors R18-R27(01Y) near the bottom of the board. I suspect they act as a low resistance shunt for current measurement via R38. It's also good to have the thermistor(TH1) between the negative contacts as another fault? detecting sensor. Not sure about the trigger temperature, I think it will be quite high because it is not mounted close to the cells.


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## bbf (May 31, 2007)

Thanks for posting the insides of the charger.
I was surprised at the complexity of the charging circuit in the charger... it looks like Sanyo doesn't skimp when it comes to the quality of its chargers.


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## koala (May 31, 2007)

I am also amazed by the number of parts under the circuit board. Sanyo definitely did not skimp on the electronics side. It's a 2-channel charger despite having 1 LED, so you can charge 1 or 2 cells. I use it everyday in the office, the size is tiny and minimalist and the ladies think it's some apple product.

For ~$18 bundled with 2xAA Eneloop, it's really something to think about. Should be available in the US now.


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## Bones (Jun 2, 2007)

Thanks for the very informative post koala.

It appears from this webpage that Sanyo incorporates a fairly extensive set of controls in all of their chargers:

http://www.energy.sanyo.com.sg/chargerproduct.asp#control


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## koala (Jun 2, 2007)

Yeap, late Sanyo stuff are quite up to quality and pretty affordable. 

I have done some charging test. The Sanyo USB Charger charges cells up to about 94-96% capacity. There is no trickle charging when charge is completed. The cell temperature rose to about 43.1C(109.58F) max at ambient temperature of 21.7C(71.06F). The cells were about ~1550mAh(La Crosse 2000mAh) cells, works out to be about 0.29C charging rate. There is no voltage rise detected during period of 2 hours wait after charging, this confirms there is no trickle charging or top-up function.

Note: The charging rate for 2 Eneloop 2000mAh cells is about 0.225C(450mA) or 1 cell at 0.425C(850mA). I was worried that the charger might not terminate properly at 0.225C. So I tried to charge two Sanyo 2500mAh cells at 0.180C. Amazingly it worked. I was wondering if it is the temperature cut or voltage, the cells discharge capacity test turned out to be within 94-96% actual capacity.


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## Beacon of Light (Jun 4, 2007)

Where can one buy this in the US, online even? I remember reading the press release of this a few months back and was excited to try it. I bought a crappy Digital USB charger but it has 4 slots for AA's or 2 AAA's and has a mini LCD with the 4 segment battery indicators. Not sure how to test if there is trickle charge or not, but a set of 4 batteries takes hours to charge to complete status. I think I paid $15 for the charger with 4 batteries at a dollar store.


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## koala (Jun 4, 2007)

Don't expect this Sanyo USB Charger to charge any faster than the one you have. Two empty - 2500mAh AA cells will take approx. 5 hours 30mins.

I don't know where you can get it in the states, have you tried ebay? I bought it here http://www.onlineshop.com.sg/index.php?main_page=product_info&cPath=3_38&products_id=3659


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## Beacon of Light (Jun 4, 2007)

Haven't tried Ebay, I will give it a go.


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## AlexLED (Feb 11, 2010)

Thanks for this Tip, sounds really great, so I bought this charger on my last trip to Asia ! 

Very useful for charging batteries from cordless phones.


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## Overclocker (Mar 7, 2012)

so is this temp cutoff or -dV?


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## koala (Mar 14, 2012)

Both, temp cutoff for second protection, -dV comes first. Springs are quite weak, might have to wedge them out.


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## reppans (Mar 15, 2012)

Talk about bringing back an old thread....

Thanks though, made me search for mine, which thankfully I have found . I'm in sudden need of an ultra-portable single cell travel charger for my Eneloops... 5 yrs later, I don't think this can be beat.

Quick question, I just noticed the input ma says "500ma max." Do you think there will be a problem if I use a solar panel that puts out 5V/1a?


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## Overclocker (Mar 15, 2012)

koala said:


> Both, temp cutoff for second protection, -dV comes first. Springs are quite weak, might have to wedge them out.



yeah weak springs could be an issue. maybe you could bend them out a bit and fill in with silicone sealant

so it's -dV then. thanks. btw have you confirmed this empirically?


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## Lyubo Yanev (Mar 16, 2012)

According to http://www.stefanv.com/electronics/sanyo_usb_charger.html its "voltage peak detecting".
Is this the same as -dV??


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## Street (Mar 17, 2012)

I have this charger about two weeks,but I am not sure if has two independent channels.Koala are you sure that this charger has independent channels?


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## koala (Mar 19, 2012)

- 6 kinds of protection feature: *Individual Charging control*, Peak voltage control, Minus delta Voltage detection, Temperature Control/ protection, Alkaline battery Detection**, Short circuited Cells detection**. (**LED light will turn off within 40 seconds)​


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## f22shift (Mar 19, 2012)

can i use this with a 1a usb charger. like the apple charger. meaning would it just pull 500ma for the his 1a charger? or can it be used only with 500ma current like a pc.


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## koala (Mar 21, 2012)

It will work with all types of USB chargers. I modded mine to work with my 5V phone charger years ago. I have now changed to a phone with microusb, I might mod it again. :naughty:
I hooked it up to my power supply limited to 5V, no it won't draw more than 500mA. I also checked the current spikes with a scope, it's fine.


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## Overclocker (May 24, 2013)

wtf can't find this charger anymore!

too bad coz it's such an excellent little charger


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## Trevtrain (May 24, 2013)

*Sanyo NC-MDU01 with Solar Panel?*

Well this is a very interesting thread for me.

I have two of these chargers which see EDC backup roles when I'm out and about. I use a Maha C9000 at home.

Koala, you seem to have much better knowledge than I do as well as access to some nice test equipment. :wave:
Here is a question or problem you may be able to help me out with.

I sometimes use these chargers when away on camping trips. I have a couple of Cottonpickers solar panels which output to USB (see CPFmarketplace for details) as well as a few of his USB Li-Ion chargers for my other lights. I also want to run these Eneloop chargers from the panel, but I'm having some confusing results with the status LED.

When the weather fine and there are no clouds, the chargers function correctly.
On cloudy days or when there is intermittent passing cloud, the panels of course do not output their full capacity and may drop below the required 500mA.
In this situation, the charger LED displays a series of 3 flashes.
Very short - short - longer (normal pulse)
Very short - short - longer (normal pulse)
This sequence is not mentioned in charger manual, nor anywhere else I can find on the Web. My best guess is that it is an undocumented feature that is supposed to indicate some kind of fault condition.


I suppose I have two simple questions.


Will a lower input current cause any damage to the charger?
Is the charger actually continuing to put any charge at all into the cells in this state? (But maybe at a lower rate) 
 

I have a few cheaper "dumb" USB chargers - the silver coloured kind you find for a couple of dollars in the Chinese web stores. These output 130mA to 160mA under ideal conditions. Using my DMM I have found that they will keep charging on cloudy days, albeit at a much slower rate. Sometimes as low as 20mA. 

However I don't seem to be able to get an output reading on the NC-MDU01 using the DMM, which I have guessed may be due to some kind of current "pulsing" (possibly for voltage detection?) rather than a steady input.


I would prefer to use the Eneloop chargers to take advantage of the higher charge rates and termination "smarts" but there is little point in leaving them out and connected to the panels if they are not charging at all when the power drops.

My workaround until now has been to put a Li-Ion pack (4*18650 box or ML-102) in between the panel and the Eneloop charger as a buffer but then I have to be quite mindful of keeping the Li cells out of direct sun. I'd rather have less equipment lying about to keep an eye on.

Is there any way you could test the Eneloop charger with a lower input current - even down to say 50mA - and work out what is going on?

I've tried contacting the manufacturer via their web form but have had no reply on this question.

Any help on this would be appreciated. 
Thanks.


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## Trevtrain (May 24, 2013)

Don't want to post links here but they are certainly still available at two places here in Australia
Google "Battery Choice" or "Batteries Australia"

Of course, depending on your location, shipping might make it economically ridiculous.



Overclocker said:


> wtf can't find this charger anymore!
> 
> too bad coz it's such an excellent little charger


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## koala (May 25, 2013)

Trevtrain said:


> I suppose I have two simple questions.
> 
> 
> Will a lower input current cause any damage to the charger?
> Is the charger actually continuing to put any charge at all into the cells in this state? (But maybe at a lower rate)



Lower input current will definitely not cause any problem to the charger but I will have to do some test to answer your other questions.

Unfortunately it seems that it has found it's way to extinction...


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## Overclocker (May 26, 2013)

*See Rule #3 Do not Hot Link images. Please host on an image site, Imageshack or similar and repost – Thanks Norm*

this one seems to be a decent repacement... but we really wouldn't know until koala tests it


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## Trevtrain (May 26, 2013)

Koala

Thanks for your reply. I was at the website about a week ago and I'm sure the "end of production" message wasn't there when I downloaded the manual. Perhaps this is a recent update and may explain why they couldn't be bothered to respond to my email enquiry.
I wonder if they have plans to produce anything as a replacement?

From what I have learned in other places, I guess there may be a minimum current required to power the unit so as to reliably be able to perform -dV detection. I suspect the LED flash codes I described are an error message but it would be nice to know for sure.

Cheers


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## TinderBox (UK) (May 26, 2013)

Amazon UK has it for sale for £13.90 , just search for "Sanyo Eneloop USB Charger"

John.


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## CaesarI (Aug 9, 2013)

Amazon USA has them in stock again. Interestingly the package indicates they are distributed by Sanyo Canada, so maybe these are an import?
My computer has a feature that lets it charge USB devices from the battery even when the computer is otherwise powered off so I don't have to worry about leaving a sensitive electronic device like the Sanyo USB charger plugged into the wall. 
The LED light on the charger is annoyingly bright at night. It could be 1/10th as bright and still be functional.
I'm planning on seeing how well it works with the Suntactics Solar USB Charger http://www.amazon.com/dp/B003ZFQUWO/?tag=cpf0b6-20

-Morgan


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## Trevtrain (Aug 10, 2013)

CaesarI said:


> I'm planning on seeing how well it works with the Suntactics Solar USB Charger http://www.amazon.com/dp/B003ZFQUWO/?tag=cpf0b6-20
> 
> -Morgan



As you will see in my post #21, you may find this charger problematic with a solar source.
Unless you can be sure of clear, uninterrupted sunshine, your panel may not produce enough power to run the Sayno USB model. I pretty much always use a Li-Ion intermediate now as it seems the Li-Ion charging regimes are much more tolerant of fluctuating current.

Try your solar panel on a cloudy or hazy day and see if you get the same odd blinking pattern on the blue light that I do.

BTW, if you are interested in solar charging, be sure to look at Cottonpickers offerings in the CPF marketplace. He makes some very nice panels and chargers and is a standup guy to deal with.


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## Teobaldo (Aug 12, 2013)

*Re: Sanyo NC-MDU01 with Solar Panel?*



Trevtrain said:


> When the weather fine and there are no clouds, the chargers function correctly.
> On cloudy days or when there is intermittent passing cloud, the panels of course do not output their full capacity and may drop below the required 500mA.
> In this situation, the charger LED displays a series of 3 flashes.
> Very short - short - longer (normal pulse)
> ...



I think so, since had the same behaviour in my Sanyo USB charger with my foldable solar panel Brunton Solaris 6. After using it twice my charger died :mecry:

Thank you for warning that again it is on sale, think that soon will buy one spare.


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## CaesarI (Aug 13, 2013)

*Re: Sanyo NC-MDU01 with Solar Panel?*

The advertised perk to the SunTactics charger is that it produces more power for the same light and has an auto-retry feature for dealing with clouds and other interruptions. I'll report back on success or failure. 

Also of interest the date-stamp on the batteries is 2013, May. Yet they are tagged as 2nd Generation Eneloops HR-3UTGA. I can only infer that Sanyo continues to manufacture the 2nd generation Eneloops for export alongside the 3rd and 4th generation products being sold domestically (in Japan). It would be rather obvious as to why they'd still be selling 2010, or 2011 manufacture batteries (old stock) but it is slightly less clear to me why they'd continue producing the older model multiple years after they've come out with two improvements. Updating factory equipment can't be that expensive.

-Morgan


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## Brunt The Grunt (Sep 16, 2013)

so has anyone been able to duplicate the fluctuating current issue when this is teamed with a solar panel? Anxious to know being I've got the MDU01 model hooked up to a Solio Magnesium classic model and the USB isn't compatible due to outdated technology and I'm thinking of upgrading to the newer Solio Classic 2 which should support it. Up until now I had the Energizer Duo usb charger that performed flawlessly with the panel but came across the Sanyo charger and this setup would be ideal in the outdoors for me but I don't want to invest if the fluctuating current issue has the potential to problematic in a pinch. Gonna be checking out cottonpickers post in the marketplace as well thanks


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## Trevtrain (Sep 17, 2013)

I've pretty much given up using these chargers direct on a solar panel for now. I find they work well if you can put an intermediate battery between them such as an 18650 in a ML-102 charger/supply.

It seems that the nature of NiMH charging requires a steady current for these Sanyos in order to properly detect end of charge. A solar panel cannot provide this on days with passing cloud, so the Sanyos seem to just sit there all day and never finish. I'm not sure they are even charging at all. Sanyo support never answered my email on this queston.


Li-Ion units such as Cottonpickers sells seem to be much more forgiving and will keep charging even at very low levels of current, meaning that you can harvest every bit of energy that is there to collect.

I purchased a battery box from him some time ago which is capable of accepting a charge whilst also powering the Sanyo AA chargers. You might like to confirm that the boxes he currently sells still do the same thing.


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## Beacon of Light (Aug 25, 2014)

Sorry for bumping an old thread but I figured it would be appropriate to keep it in this thread since it is about this particular charger. Is it safe to charge solar NiCads in this? There is no mention of it being hazardous (they just mention the typical do not charge primary cells) but no mention that in can do NiMH and NiCad. I'm on vacation and only have this charger with me and need to charge up those AA NiCads that are in solar outdoor lights.


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## ChrisGarrett (Aug 25, 2014)

From my Amazon link, it states 2 AA Eneloops in 4 hours, so I'm guessing 400mA-500mA per channel, is that right, since you have the charger there?

NiCads are what...300mAh or less, for AAs and AAAs, if you can still find them? 1.5C might be a bit too high for a NiCad, but I haven't played with those for almost 20 years, lol.

Chris


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## Power Me Up (Aug 25, 2014)

As far as I recall, 600 mAh is a fairly typical capacity for NiCad AAs for solar lights. AA NiCads went up to about 1000 mAh, but they tend to use lower capacity cells in solar lights...

I wouldn't expect you to have any problem charging those cells in that charger...


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## ChrisGarrett (Aug 25, 2014)

Power Me Up said:


> As far as I recall, 600 mAh is a fairly typical capacity for NiCad AAs for solar lights. AA NiCads went up to about 1000 mAh, but they tend to use lower capacity cells in solar lights...
> 
> I wouldn't expect you to have any problem charging those cells in that charger...



I was at home in L.A. in June and July and bought three different brands of solar garden lights and they all came with NiMH AA batteries, ranging from 350mA up to possibly 600mAh. I was ready to buy some Eneloops before deciding to let them be for a year, or so.

Doing a quick Google, I see 600mAh-1000mAh listed, so that charger would be fine for modern NiCad AAs, I'd imagine?

Chris


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## Beacon of Light (Aug 28, 2014)

These were cheaper solar lights from 3-4 years ago. Cells are labelled Jiawei with a Yards & Beyond logo. 200mAh. 3 cells charged and the lights worked for a bit but I didn't charge them very long, erring on the side of caution. 1 cell seems completely dead. Do the solar cells eventually go bad in these? The plastic is still intact and I cleaned the lens covering them.


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## kide (Oct 21, 2014)

There seems to be something wrong with my NC-MDU01. The first odd behavior I noticed was that the blinking LED became dimmer towards the end of the charge. Then it became so dim that it was very hard to see at all. A few charges later and then the LED might blink for a few minutes and then just stays off. 

I have tried many different USB ports and power sources and the behavior stays the same. 

I think it still charges the batteries just fine. They become slightly warm and also eventually cool down meaning that termination works. 

Today the LED started acting really funny. When plugging in the LED stayed off. But about 10 minutes later it started blinking and flashing sporadically and completely randomly. Sometimes a single short flash and sometimes the normal slow blinking, sometimes bright, sometimes dim, sometimes fading or pulsing... 

If there is a simple fault, I would like to fix it. But as long as it charges ok, I don't want to mess with it. I'm interested if anyone have experienced anything similar with their NC-MDU01. 

I'm sad to see that this charger is now discontinued. Hopefully they will make a new and better version with separate (and dimmer) LEDs for each slot.


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## hiuintahs (Oct 21, 2014)

I have one of those chargers but haven't used it yet so may not be the best candidate to help. Your explanation makes it sound like the LED has a bad connection (ie: solder joint). That probably isn't what it is as that would just be too lucky if that was all. Check also the series resistor associated with it if you can find it.

Now you mentioned that the batteries look like they are getting charged. I'd suggest measuring the voltage to verify that. The reason I say that is that it looks as though this charger is controlled by a microcontroller.

You can see pics of the pcb here on the first post of this thread.

I think the nature of a failure in a microcontroller is that it works or it doesn't........just a guess. And the LED most likely would be controlled by this microcontroller too. So if the charge process works, it makes me think that the problem is outside the microcontroller. If the problem is the microcontroller then its unrepairable. Everything else in there looks to replaceable.

OK, I'm making some wild guess's here. I'd take it apart and just visually look things over to see if something looks burned or cracked solder joint etc. You may not be able to determine anything but worth a look before getting rid of it.


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## Richwouldnt (Oct 21, 2014)

I have been looking for one of those USB Sanyo chargers but it looks like they were discontinued several years ago and the only listing I found is a Amazon seller who wants >$200 for a NOS one, a ripoff. Unfortunately too I cannot find any one else doing a good USB powered NiMH battery charger. The stuff available seems to all be junky low current chargers with minimal electronics and no charge termination, just timed charge input if even that. Total POS chargers per the reviews.

If any one knows of a decent USB powered NiMH charger, preferably two batteries capacity, PM me a link or post about it here. Be much appreciated.


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## Trevtrain (Oct 22, 2014)

Xtar xp1 is supposed to be ok. Unfortunately only takes 1 cell at a time.

i have a few of the Sanyo models and thankfully they've all held up well so far. I wish they still made them.


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## degg (Oct 22, 2014)

Sanyo/Panasonic should redesign it without the cable and add a micro usb port instead. It would be smaller and more practical.


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## Overclocker (Oct 22, 2014)

http://www.candlepowerforums.com/vb...4-USB-Charger-Kit-(equivalent-to-Sanyo-MDU01)


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## Jobtrot (Mar 31, 2015)

I just found two of these NC-MDU01. Old stock apparently. Came with 2 vintage 2007 eneloops that still hold some charges in it and can power my 2AA LED light. Not too bad. Will observe how em old batts fare over time. I am happy enuff to get them chargers even though those eneloops that came with them dont perform too good considering the vintage. In time I can sure find someone that can make good use of it. Cant find smart chargers of similar size anywhere for AA and AAA anywhere in my neck of the wood.


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