| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the following problem: one half of the offset voltage of a hysteresis width should be given to a hysteresis comparator and the hysteresis width may be varied by variations in semiconductor process for the hysteresis comparator, although arbitrary hysteresis width can be obtained by adjusting the size of a MOS transistor, wherein the hysteresis comparator has a configuration where an input signal and an offset voltage are input into a differential pair, and a gate and a drain of a load MOS transistor coupled to the differential pair are connected in a cross-multiply fashion. Ž<P>SOLUTION: The hysteresis comparator includes a first comparator and a second comparator. The first comparator includes a differential pairs 30 and a load section 31. A difference input signal Vin and a threshold Vth are input into the differential pairs 30. The first comparator has hysteresis characteristics. The second comparator includes a load section 32 and a differential pairs 30. The second comparator does not have hysteresis characteristics. Operation is switched between the first comparator and the second comparator by an output Vout of the hysteresis comparator. Since voltage for transiting the output Vout is determined only by the threshold Vth when the second comparator portion operates, the hysteresis comparator is not affected by semiconductor process. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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