| 摘要 |
PURPOSE:To prevent the brekage of a semiconductor junction/separation structure and to secure stable oscillation, by discharging a capacity element so that the junctures of said element is not set at a negative potential. CONSTITUTION:When the potentials 16 and 17 of a capacity 18 are less than the threshold levels of elements 31 and 33, switch elements 32 and 34 as well as 12 and 14 are turned off with elements 12 and 13 turned on respectively. Therefore, a point 16 is grounded and the electric charge is supplied to a point 17 from a current source 10 via the element 13. Thus the potential is increased at the point 17. When the potential of the point 17 reaches the threshold level of the element 33, the element 34 is turned on. Thus the reset control is given to an FF19 to invert the output. A delay time is produced in a period when the output of the FF19 is inverted after the element 34 is turned on. During this delay time the capacity 18 performs discharging from the point 17 with the point 16 kept grounded to reduce the potential down to a point near zero. In such a way, the voltage of the capacity 18 is set at zero immediately before the elements 12 and 13 are achned to ON from OFF to avoid a negative potential of the point 16. At the same time, a negative potential is avoided at the point 17 when elements 12 and 13 are changed to ON from OFF. |
