The R5422NxxxC/E Series are protection ICs for over-charge/discharge of rechargeable one-cell Lithium-ion (Li+) excess load current, further include a short circuit protector for preventing large external short circuit current. Each of these ICs is composed of three voltage detectors, a reference unit, a delay circuit, a short circuit protector, and a logic circuit. When charging voltage crosses the detector threshold from a low value to a value higher than VDET1, the output of COUT pin, the output of over-charge detector/VD1, switches to low level, charger's negative pin level after the delay time by setting an external capacitor. After detecting over-charge the VD1 can be reset and the output of COUT becomes high when the VDD voltage is coming down to a level lower than "VREL1", or when a kind of loading is connected to VDD after a charger is disconnected from the battery pack while the VDD level is in between "VDET1" and "VREL1" in the R5422NxxxC/E version. The output of DOUT pin, the output of over-discharge detector/VD2, switches to low level after internally fixed delay time passed, when discharging voltage crosses the detector threshold from a high value to a value lower than VDET2. After R5422NxxxC/E Series detect the over-discharge voltage, connect a charger to the battery pack, and when the battery supply voltage becomes higher than the over-discharge detector threshold, VD2 is released and the voltage of DOUT becomes "H" level.