单片4(1/2)位十进计数器 ICM7224是美国 INTERSIL 公司的产品,它是十进计数,寄存,译码,液晶驱动四合一的 CMOS 大规模集成电路。使用时外接元件很少。最高计数频率达25MC。工作电压3～6V,静态电流小于50μA,适于组成小型便携式仪器,引线排列见图1。液晶显示器可采用上海电子管厂的4(1/2)N49,其排列见图2。这样,一片 ICM7224和一片液晶显示器就能构成一个四位半十进计数器,最大计数值19999,具体线路见图3。如用 Monolithic 4 (1/2) decimal counter ICM7224 INTERSIL company is the United States products, it is ten count, register, decode, LCD driver quadruple CMOS integrated circuit. Few external components when used. The maximum count frequency of 25MC. Operating voltage 3 ~ 6V, quiescent current is less than 50μA, suitable for small portable devices, lead arrangement shown in Figure 1. LCD monitor Shanghai Electronic Tube Factory can be used 4 (1/2) N49, the arrangement shown in Figure 2. In this way, an ICM7224 and a liquid crystal display can form a four and a half decade counter, the maximum count value of 19999, the specific line shown in Figure 3. If used