型号 / 厂家，封装，批号，备注，订购

DM74LS490M / National Semiconductor,Datasheet,07+,BCD-Output Decade Up 订购 PDF文档

DM74LS490N / National Semiconductor,Datasheet,07+,BCD-Output Decade Up 订购 PDF文档

DM74LS491 / National Semiconductor,Datasheet,06/07+, 订购 PDF文档

DM74LS491A / National Semiconductor,Datasheet,07+,10-Bit 订购 PDF文档

DM74LS491AV / National Semiconductor,Datasheet,07+,10-Bit 订购 PDF文档

DM74LS498A / National Semiconductor,Datasheet,07+,Octal Shift Register 订购 PDF文档

DM74LS498AJ / National Semiconductor,Datasheet,06/07+,Octal Shift Register 订购 PDF文档

DM74LS498AN / National Semiconductor,Datasheet,06/07+,Octal Shift Register 订购 PDF文档

DM74LS498J / National Semiconductor,Datasheet,06/07+,8-Bit Shift Register 订购 PDF文档

DM74LS502 / National Semiconductor,Datasheet,07+,8-Bit Successive App 订购 PDF文档