Solar shed-light teardown (with schematic)

An intriguing solar shed light that uses a YX8183 chip I've not come across before. It's from the same company that makes the generic 4 pin control chip used in most solar garden lights, but this one is optimised for use with lithium cells - both the common 3.7V type plus the LiFePO4 3.2V type. The chip has two distinct sections. The charge control circuit, which allows current to flow from the solar panel to the lithium cell until it is fully charged, and a section with a current regulated LED supply that uses a single low value resistor to set the current. Charge current is literally whatever the solar panel can provide until the internal charge control circuit cuts it off. The recommended maximum is 600mA. The LED current control is based on sensing a 90mV threshold across a sense resistor, so a 10 ohm resistor will allow 9mA to flow, while a 1 ohm resistor will allow about 90mA to flow. In this case a 0.33 ohm resistor has been used to set a current of about 270mA. In use the light provides a useful level of light in a dark room. It could be useful as part of the lighting for an off grid application. This unit was bought locally at Jac's, a chain of island stores that carries things like housewares, DIY supplies, toys and seasonal things like solar lights. Theoretically the light can be hacked to use a LiFePO4 cell by simply lifting or cutting pin 6. The LED current can be adjusted by swapping the sense resistor, and it's also possible to adapt it to turn on automatically at dusk by adding the 1K resistor shown in the datasheet between the solar panel +ve and pin 2 after it has been isolated from the PCB. If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- http://www.bigclive.com/coffee.htm This also keeps the channel independent of YouTube's algorithm quirks, allowing it to be a bit more dangerous and naughty. #ElectronicsCreators