I ordered 6 pcs. of which only 2 worked out of the box. Four had components either dropped off the board already at arrival or during handling and assembly. I managed to solder them back on the board and three where back in business, however the last has a "heavy load ~25 ohm" at the output of the MAX8903A LiPO so no luck here. I can't find the short so probably a defective component or some short underneath a component - given up. I think the product and function is great, but soldering quality is terrible. I adjusted the max charging current Ichg as well as the Iin according to the datasheet of the MAX8903A, since the resistor value calculations wasn't in the product documentation.
Does exactly what it should with many useful features, some of which I used in my battery pack project. Used it to balance charge 5 18650 batteries and works brilliantly with the ability to configure parameters such as overvoltage and undervoltage thresholds using the integrated Atmega 328 MCU. Values like individual battery voltages and drawn current (via a coulomb counter) can be queried via registers as detailed in the BQ7692 IC datasheet. Overall an excellent piece of kit for the money!
A really simply idea that is well executed. I use it to power some remote sensors from a 4000mAh battery with a small solar panel as a charging source, it does exactly what the designer said it would. The charge monitor is perfect for reporting the system health back to the host system while the 5V boost output is a very hand addition to the 3.3V output. Nice!
I've put the device attached at a solar cell with 5V under full sunlight, a LiPo (2000mAh) and a LED (10mA) as load at the 3V3 output. Everything worked fine and the would be loaded slowly (not always sunny) from 3.9V to 4.2V. But immediately when the battery was fully loaded the output voltage begans to fluctuate at 2.7V (DMM measurement) and as a result the LED blinks. I attached some big capacitors (2 x 470uF) at Vout, but it was not possilbe to flatten the fluctuation. Also shadowing the solar cell (output down to 3V) does not help
With that result the product is unusable
If there is any improvent I can do, please let me know
Input voltage should be kept below 4.2V. It is a boost converter on the input. Not all input voltage / battery type combinations work well. Some input voltage tweaking might be necessary for optimal results. Try with 1V on the input, that might yield cleaner output voltage.
The charger perfectly works. Used to charge a 3.75V/4600mA Lipo battery kept from a broken tablet with a small solar panel 6V/1.1W/200mA. The presence of a Control Monitoring V+ is helpful to correctly pointing the solar panel. Good packaging, fast delivery from Slovenja to Italy (although no tracking number available)
I was working on my 1st solar project and was trying out a of different methods to charging the battery. This performed well & was easy to use. He has another type of charger, so do your homework on which one you want. The quality is top notch.
This board is well thought out & seems to work well I would have. It does require 5v. The only caveat is the adjustments weren't obvious to me; but after reading the datasheet I was able to get my head around it. Response to questions were courteous. There is no "blinky" loaded, but if you hook it up to a serial monitor, it does put out some data (temp and something else) so you do know it's working right away. Seems to draw more than the RocketScream version, but this seems to handle the solar panel better.