The reading lamp consists of a small solar panel, a standard UPS style lead acid battery, and an LED circuit board. The circuit board contains a low power solar charge controller (regulator), a set of 8 white LEDs, a switch, an LED current regulator, and a low voltage disconnect circuit.
Solar lights outdoor garden
The circuitry will insure a long battery life by preventing over charging and excessive discharging. The circuit was designed to work with lead acid batteries, it should also work with a string of 10 NiCd cells. Both the charge controller and LED regulator circuits can be used independently for other applications.
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