| 摘要 |
PROBLEM TO BE SOLVED: To provide a protective element which protets a battery pack from the defects in a load and which can reset by itself when the defects are eliminated. SOLUTION: A protective element 10 includes a switch 12, a control FET 14, and three resistors 16, 18, and 22. In a normal state, the switch 12 conducts and the control FET 14 does not conduct. When a short is detected, the control FET 14 conducts and the switch 12 is turned off. The switch 12 keeps a non- conduction state until a load 38 is separated from the protective element. The protective element 10 also includes a temperature sensor 24 which turns the switch 12 off at higher temperatures and a current controlling element 28 which gives the upper limit to the current in the protective element 10. By applying control signals to the switch 12 and a gate electrode of the control FET 14, the current in the protective element 10 can be modulated. |
