USB for DIY charger 5V Step-Up Power Module operates at an input voltage range of 3.7V~5.5V at a 1A charging current. This Lithium Battery Charging Protection Board uses high-quality USB iron with a cheap display port video card and Integrated Circuits. It comes with an onboard LED to indicates the Charging and discharging status. The Red LED flashes under charging condition. Whereas when fully charged the RED LED glows for a long time. These module functions with Internally installed charging and discharging power MOS. It operates at a preset charging voltage of 4.2V at a precision of ±1%. Moreover, this battery protection board features Integration charging management and discharging management.
It supports a maximum of 8uA standby current. As a result, the low standby current on the charger saves energy. This lithium battery protection board supports trickle mode and zero voltage charging. Li-ion batteries cannot absorb overcharge and does not receive trickle charge when full. The wake-up feature, or “boost,” in lithium-ion chargers allow recharging if a Li-ion battery even has fallen asleep due to over-discharge. The sleep condition occurs when storing the battery in a discharged state in which self-discharge brings the voltage to the cut-off point. The Boost applies a small charge current to raise the voltage to between 2.2V/cell and 2.9V/cell. Thereby activates the protection circuit, at which point a normal charge commences. So the BAT discharging voltage is considered as 2.9V with a discharging efficiency of 85%(input 3.7V output 5V/1A).