| 摘要 |
PURPOSE:To prevent the deterioration of control accuracy as well as an unstable operation due to a hunting by providing the 1st blind sector as well as the 2nd blind sector having larger width than the 1st blind sector to control the operations. CONSTITUTION:A blind sector is first set at a region 1 with the potential set between V2 and V3, and T<V1 is satisfied for the control voltage T. Under such conditions, the potentials of output terminals (a)-(d) of comparators C1-C4 are set at L, L, H and H respectively. At the same time, an output Q is set at L to perform the control to the quantity to be controlled. In the case of V1<T< V2, the control proceeds with no change given to the state of an FF. The potentials of the terminals (a)-(d) are all set at L with V2<T<V3, and therefore the FF is set to discontinue the control. The control is kept under a pause state after the FF is once set even though the voltage T varies to V1<T<V2 or V3<T<V4. Then the FF is reset to start the control again when the voltage T satisfyes T<V1 or V4<T and is set to the outside of the region II. |
