| 摘要 |
PURPOSE:To make longer the life by eliminating the DC component integrated on the device, through arbitrary selection of alternating signal two or more types, in the circuit alternately driving the display unit. CONSTITUTION:In the display unit such as a digital wrist watch, as the input 8, the alternating signal of normal duty of 50% and 32 Hz and the alternating signal of 100 Hz is inputted to the input 9. Further, in case of display of 1/10 second digit of a stop watch, since the segment signal 7 and the input 8 in 32 Hz are not synchronized, DC component remains every one period of 10 Hz. Thus, the logic of the control input 10 is taken as 1 and 100 Hz is inputted as alternating signal, then it is synchronized with the signal 7(10 Hz), no DC component is remained. Further, in the display of normal second or more, the logic of the input 10 is taken as 0 and with the input of 32 Hz, since it is synchronized with the signal 7, similarly no DC component is remained. |
