Electric charger and power supply device for portable terminal

An electric charger, comprising:

• a charging circuit outputting a charging voltage in correspondence with the number of battery cells incorporated in a battery in a supply state of an external power supply;
• a charging control unit which, upon detection of connection of said battery functioning normally, said battery is charged by turning on a switch unit provided in a connection path extending from the charging circuit to the battery;
• and
• a cutoff releasing circuit which, upon detection of connection of said battery in a cutoff state caused by overdischarge, outputs a releasing voltage for releasing the cutoff state set by over-discharge of the battery,
• wherein the cutoff releasing circuit comprises:
• a first FET switch connecting a drain to the output of the charging circuit;
• a second FET switch which has a source connected to the source of the first FET switch and a drain connected to the battery and which is ON/OFF-controlled by the charging control unit, and
• a switch control circuit which, upon connection of said battery in a cutoff state caused by over-discharging, turns on the first FET switch in accordance with a battery abnormal signal outputted from the battery, thereby applying a charge voltage for releasing the cutoff state to the battery via a parasitic diode of the second FET switch in an OFF state.