发明授权
US5986540A Sound signal generating device 失效
声音信号发生装置

Sound signal generating device
摘要:
A sound signal generating device capable of generating an alarm sound signal and voice signal for a prolonged period of time having a power supply, a memory for storing data in relation to a help sound signal digitally, a D/A converting circuit for converting the stored data into an analog signal, a sound output circuit for outputting the help sound signal in response to the analog signal and a switching circuit for selectively applying the power supply to the sound output circuit when being activated by a control signal. The sound signal generating device also has a control circuit for generating a first control signal to enable a successive reading of the stored data and activate the switching circuit at the same time of the reading and for generating a second control signal when the reading is completed to deactivate the first control signal for a predetermined interval and then reset the same. When the first control signal is deactivated during the predetermined interval, the switching circuit disables the sound output circuit to thus minimize the consumption of power supply.
信息查询
0/0