To provide a new and improved protecting circuit for an external battery pack, especially for the battery pack for a cellular phone.
The protecting circuit is equipped with: an assembly of switches which controls the connection of the output of a battery pack with a load; a detector which detects a resistance at the terminal of the load; a first comparator which generates a first output signal when it compares a resistance having a predetermined maximum value with the detected resistance, and the latter is larger than the former, and generates a second output signal when the latter is smaller than the former, a second comparator which generates a third output signal when it compares a resistance having a predetermined minimum value with the detected resistance, and the latter is smaller than the former, and generates a fourth output signal when the latter is larger than the former; and a second detector which is connected with the respective comparators and generates a controlling signal for closing the assembly of switches when the value of the detected resistor exists inside a scope between the maximum value and the minimum value, and generates a controlling signal for opening the assembly of switches when the value of the detected resistance exists outside the scope.
| JPH04344129 | ELECTRONIC APPARATUS |
| WO/2010/044877 | LIFE SAFETY DEVICE WITH EXTENDED SHELF LIFE |
| JP3084420 | [Name of invention] Structure of an automobile battery emergency starter |
| JPH0919071A | 1997-01-17 | |||
| JPH0729554A | 1995-01-31 | |||
| JPH09308114A | 1997-11-28 | |||
| JPH08308121A | 1996-11-22 | |||
| JPS6264229A | 1987-03-23 |
Kurata Masatoshi
Satoshi Kono
Makoto Nakamura
Yoshihiro Fukuhara
Takashi Mine
Toshio Shirane
Sadao Muramatsu
Nobuhisa Nogawa
Kocho Chojiro
Naoki Kono
Katsu Sunagawa
Katsumura Hiro
Tatsushi Sato
Takashi Okada
Mihoko Horiuchi
Takenori Masanori
Takuzo Ichihara
Yamashita Gen