These octal bus transceivers are designed for asynchronous two-way communication between data buses. These devices transmit data from the A bus to the B bus or from the B bus to the A bus, depending on the level at the direction-control (DIR) input. The output-enable input can be used to disable the device so that the buses are effectively isolated.

The -1 version of the SN74ALS645A is identical to the standard version, except that the recommended maximum I_OL is increased to 48 mA. There is no -1 version of the SN54ALS645A.

The SN54ALS645A and SN54AS645 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALS645A and SN74AS645 are characterized for operation from 0°C to 70°C.

• Bidirectional Bus Transceivers in High-Density 20-Pin Packages
• True Logic
• 3-State Outputs
• Package Options Include Plastic Small-Outline (DW) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs

• IOL (Max) (mA)
• 12
• IOH (Max) (mA)
• -12
• Technology Family
• ALS
• Rating
• Military
• Operating temperature range (C)
• -55 to 125

SN54ALS645A的完整型号有：8403301RA、8403301SA、SN54ALS645AJ、SNJ54ALS645AJ、SNJ54ALS645AW，以下是这些产品的关键参数及官网采购报价：

8403301RA，工作温度：-55 to 125，封装：CDIP (J)-20，包装数量MPQ：1个，MSL 等级/回流焊峰值温度：N/A for Pkg Type，引脚镀层/焊球材料：SNPB，TI官网8403301RA的批量USD价格：21.038（1000+）

8403301SA，工作温度：-55 to 125，封装：CFP (W)-20，包装数量MPQ：1个，MSL 等级/回流焊峰值温度：N/A for Pkg Type，引脚镀层/焊球材料：SNPB，TI官网8403301SA的批量USD价格：24.872（1000+）

SN54ALS645AJ，工作温度：-55 to 125，封装：CDIP (J)-20，包装数量MPQ：1个，MSL 等级/回流焊峰值温度：N/A for Pkg Type，引脚镀层/焊球材料：SNPB，TI官网SN54ALS645AJ的批量USD价格：16.254（1000+）

SNJ54ALS645AJ，工作温度：-55 to 125，封装：CDIP (J)-20，包装数量MPQ：1个，MSL 等级/回流焊峰值温度：N/A for Pkg Type，引脚镀层/焊球材料：SNPB，TI官网SNJ54ALS645AJ的批量USD价格：21.038（1000+）

SNJ54ALS645AW，工作温度：-55 to 125，封装：CFP (W)-20，包装数量MPQ：1个，MSL 等级/回流焊峰值温度：N/A for Pkg Type，引脚镀层/焊球材料：SNPB，TI官网SNJ54ALS645AW的批量USD价格：24.872（1000+）