Low-current consumption CMOS comparator using charge-storage amplifier for A/D converters

This paper describes a low-current consumption CMOS comparator using a charge-storage amplifier for A/D converters. A comparator is usually composed of an amplifier and a latch. Because the amplifier consumes higher amounts of current than the latch, the comparator needs a low-current consumption amplifier. In this paper, we propose a new charge- storage amplifier for a low-current consumption comparator. The charge-storage amplifier consumes a constant current only during the charging period to internal capacitors, which are used as load devices instead of transistors or resistors. The comparator was designed and fabricated using a standard logic CMOS technology. Consequently, the charge-storage amplifier consumed less than one-half of the current of a normal amplifier that had transistor loads.