| 摘要 |
PROBLEM TO BE SOLVED: To limit a strobe charge current at low temperatures by arranging a temperature sensor in a circuit in order to improve the service life of a battery at low temperatures, in a strobe circuit. SOLUTION: In relation to a time constant of oscillation determined by C and R in the past, a thermistor is added. When it is assumed that the resistance of the thermistor is R(t), the time constant is obtained from C×R×R(t). Since the resistance R(t) becomes sufficiently greater than R at low temperatures, the time constant can be obtained from CR(t), the time constant increases as compared with that at ordinary temperatures, an oscillation frequency is lowered and a current flowing to a transformer is reduced. COPYRIGHT: (C)2007,JPO&INPIT |
