I purchased the Solar Charger Shield by Seeed Studio and would like to know if some one is using it or tried to use it with a solar panel.
Questions:
1- Where can I get a connector to match the Solar Panel Jack ?
2- What type of Solar panel should I use to match the board spec’s ?
3- I need clarification regarding the Charging spec’s:
- Input voltage
- Low power threshold voltage
- Charge voltage
- Precharge threshold
I downloaded the datasheet; but the included information is terse and the schematic is very hard to read.
Thank you in advance
Rej.
Thank for the info.
I found a hit in the Seee Studio Forum which mentiones the connector for the panel. Have a look at the following link:
seeedstudio.com/forum/viewtopic.php?f=4&t=695&hilit=connector
This is exactly what I need to connect the Solar Panel to the Shiled. A final caveat, there is a minimum order of qty: 100 for the pins & qty: 10 for the connector.
Is it possible to obtain the datasheet (English version) for the CN3083 chip. This will help me figure out what these voltages I mentioned earlier are all about. Thanks. Rej.
Carlos,
With reference to the Solar panel and your reply, I purchased the PowerFilm 3.6V 100mA Flexible Panel and find that it’s not supplying enough voltage to keep the 3.7V - 1000mAh LiPo Battery charged. Unless I’m missing something, if I was to start again I would go with the PowerFilm 4.8V 100mA Flexible Photovoltaic Module (RB-Iow-08). Also, keep in mind that these modules are not UV-stabilized; therefore, should not be used in the direct sunlight. Consequently, the charge voltage (3.6VDC) is too low if not used under direct sun light condition.
Carlos,
Thank you for the clarification, much appreciated. I was starting to believe that my shield was faulty or damaged. Too bad we can’t get the English version of the CN3083 datasheet. Google is better than learning Chinese I suppose.
Regarding your photocell suggestion, I looked at it on your WEB site, and the only concern I have is the 8Voc. Should I install some kind of protection between the photocell and the shield ? I’m afraid the 8VDC will damage the shield if the photocell gets accidently disconnected & reconnected. What do you think ? I definitely need another photocell to take advantage of the solar energy.
Finally, were you able to get a better copy of the schematic ?
Carlos,
I’ve used the USB connector to fully charge the battery (RB-Spa-109) the first time I got the shield. As a matter of fact, this is the only way I can charge the battery, since the photocell I purchased (RB-low-05) does not supply enough voltage to charge the battery, i.e., the battery dies after a day or so of usage with the Photocell connected. One drawback of using the USB is that the output voltage (5VDC) gets disconnected internally when the USB is charging. I assumed this is normal – do you see the same on your side ?
As far as Seeed Studio is concerned, I hope you have better luck than I have to contact them. I’ve already sent them an e-mail, tried to access their forum without success and I have yet to hear back from them. They must be very busy…
By the way, I saw a 5.5VDC Photo cell on the Seeed Studio site for the Solar Charger (I assume). Are you going to get some of these ?
Regards,
Rej.
Basically, when I connect the USB cable to USB charging Jack (J5) to charge the battery, the output voltage (5VDC) to the Arduino goes to 0 and it remains off until I disconnect the USB cable from J5. If I read the schematic well, this must be related to Q1 and Q2 turning off when the USB voltage (5 VDC) is applied to the Charger.
Rej.
Carlos,
Thanks for the info about the Power Connector, I’ll order a few. Regarding my problem with the USB jack and 5 VDC output. I investigated and found the Schottky diode D2 open; therefore, preventing the 5VDC from reaching the DC/DC converter (U4) when charging power comes from the USB. So much for the QA on this board. I also noticed that you’re out of stock again for this board. I’ll see if I can replace this faulty diode.
I managed to replace D2 on the board with a 1N5819 and now I can charge the battery with the USB charging jack and keep the Arduino powered with the 5 VDC output. Much better and less disruptive way to operate 
I noticed a strange behavior with the charger when operating with the solar panel jack. While testing my fix with a variable power supply (3 – 6 VDC) on to the solar panel jack, the charge red LED always stays on (for 3 days with a 5 VDC input voltage) even with a fully charged battery. This behavior seems to be linked to the current going through the output load (tested with a 20ma and 100ma output load). One way to make the charger LEDs to switch from red to green is to momentarily unplug the output load while keeping a voltage on the solar panel jack with a fully charged battery. Did you observed the same with your charger ? Thanks again for you input.
Rej.
As mentioned earlier, I still need more information concerning the voltages in the datasheet. Hopefully I’ll find more as time/testing progresses. With regards to the load current controlling the Charging / Charged (Red / Green LEDs) status, do you have any suggestion, besides unplugging the load or used the USB input, I can use to verify that the battery is fully charged when the solar panel jack is used ? Thanks again.
If I understand you well, although the status shows charging (red LED on), it is not possible to check the status of the battery since power is drawn from the supply (the solar panel in this case). How about the Charge voltage, can voltage across the battery be monitored to check if the battery is fully charged? Thanks.
Rej.
Thanks for the update, this is exactly what I was looking for. Any prediction regarding the availability of the new board ? When will it be available and will it address some of these issues ?
Rej.
I’m trying to figure out the necessary current from the solar panel to charge the battery. As mentioned earlier the voltage must be between 4.6 and 6 Volts; however, what’s the required minimum current / power from the solar panel to charge the battery ?
Rej.
Just received a new Solar Charger V1.1 and I noticed a few changes if compared with the previous V1.0.
- Some components have been moved around on the board, i.e., U1 is now next to battery connector
- The battery connector is different an shows a different polarity
- The online documentation does not reflect these changes
I’m reluctant to apply power to the new board with fear that something will go if I use the old version’s instructions. Can someone supply me with the revised instructions, schematic and board layout for this new board. Thank you in advance.
Rej.
Hi,
I am sorry for the late reply .
1 . Where can I get a connector to match the Solar Panel Jack ?
robotshop.com/productinfo.aspx?pc=RB-See-22
2. What type of Solar panel should I use to match the board spec’s ?
Panel output voltage level is 4.5V-6.5V , we suggest use the solar panel that output more than 5V .
seeedstudio.com/depot/solar-panel55v-120ma-p-618.html?cPath=73
seeedstudio.com/depot/solar-panel55v-60ma-p-617.html?cPath=73
3. I need clarification regarding the Charging spec’s:
Input voltage :
4.5-6.5V – to charger IC , which come from solar panel
0.7-4.2V – to boost IC, which come from battery
Low power threshold voltage:
3.7V – when input lower than 3.7V , the charger IC will go into sleep mode
Charge voltage:
4.2V – charge the battery stable (when into constant voltage mode)
Precharge threshold:
3V – when FB pin input(battery voltage) is 3v , then go into precharge mode, constant current
The solar charger is a stackable shield to Arduino compatible platforms, enables adaptive battery power and act as energy harvester for in-field charging. You may use various batteries just to shift up for 5V output, or put on Li-ion battery and solar panel to form an autonomous sensor unit.http://sunrent.de/smileynormal.ico
Welcome to the RobotShop Forum rleto577!
The Solar Charger is a nifty Arduino shield and can prove very useful.
Answers:
]We have contacted the manufacturer and will let you know the exact model for the JST 2-pin input connector. We will keep you posted./:m]
]Any solar panel that can provide a voltage from 0.9V to 4.2V can be used with the shield. A good example is the PowerFilm 3.6V 100mA Flexible Panel./:m]
]The Input Voltage is the voltage that can be provided to the Input JST 2-pin connector in order to charge the battery.
Low power threshold voltage, Charge voltage, and Precharge threshold are internal vales to the charger. They are specifically intended for taking good care of LiPo batteries by charging and discharging them properly./:m]
A very good battery for this charger would be a 3.7V - 1000mAh LiPo Battery.
It is rather intriguing that the panel is not able to charge the battery. It is specifically within the operating range specified in the SeeedStudio (and RobotShop) product description.
Also, thank you for digging up the JST connector specs, they will be very useful for everyone:
The closest thing to an English version of the dataset for the CN3083 (the main charging chip that is doing all the work in the charger) is this google translation.
Upon closest inspection of the CN3083 chip and revisiting the solar charger specks, the charging voltage should be between 4.4V and 6V in order to maintain a charging voltage of 4.2V.
We will correct our product description immediately in order to reflect these changes and will test the charger with the corresponding panel in the near future.
In short, you are right: a panel that provides a higher voltage should work better with the charger (which makes a lot of sense) Thank you for catching that mistake. 
The Voc only applies when the leads are disconnected. I would not be too concerned about the temporary overvoltage caused by it when connected while in full sunlight.
In order to test your charger, you could connect it to a USB port and charge it form there, I have been doing that and it works very well.
I invited the people from Seeedstudio to participate in this thread in order to get their expertise and further specs and information about the solar charger. We should hear form them soon.
Indeed SeeedStudio is very busy lately. And yes we are going to list their new products soon.
Regarding the 5VDC being internally disconnected, what do you refer to exactly?
