| 摘要 |
PURPOSE:To reduce a well current being a cause to the production of latchup by splitting a charging capacitor into two and grounding each end. CONSTITUTION:When an FF12 is set, transistors (TR) 6, 7 are turned on, a current I4 flows as shown in solid lines to charge a capacitor 91 being one of two-split capacitors. Thus, a voltage at a point VA increases linearly, but the potential at a point VB is kept to a ground potential. When the potential of the point VA reaches a prescribed value VTH, a voltage comparator 11 outputs a high level signal and the FF12 is reset. Thus, the TRs 6, 7 turn off, TRs 5, 8 turn on, a voltage of the capacitor 91 is discharged at the TR8, the flowing of the current I4 is changed into dotted lines, the charging of other capacitor 92 being one of the two-split capacitors is started, and when a voltage at a point VB reaches the VTH the same as above, the FF12 is set and the state is restored to the initial state. |
