| 摘要 |
PURPOSE:To extend comparable voltage range, by providing a plurality of comparators with different comparable voltage ranges. CONSTITUTION:The comparator consists of the 1st comparator 41 comprising the 1st CMOS comparison circuit 21, the 1st R-S flip-flop 26, and capacitors C1-C4, in which comparable voltage ranges VDD-VTHN[where; VTHN is a threhold voltage of an N channel transistor (TR)], and the 2nd comparator 42 comprising the 2nd comparison circuit 21' replacing the N channel TRs T1, T2 into a P channel TR and using a clock pulse of an inverted phase, the 2nd R-S flip-flop 26' using an NAND gate in place of an NOR gate of the 1st flip-flop 26, and capacitors C'1-C'4 and having (VDD-VTHP)-0V of comparable voltage ranges, and the output of the comparator operated at a normal operating range is selected at a switching selection circuit 50. Thus, the comparable voltage ranges can be obtained from a ground potential to the power supply voltage. |
