Rochester Electronics 74AS242N

These quadruple bus transceivers are designed for asynchronous two-way communication between data buses. The implementation of control functions provides maximum flexibility in timing. These devices allow data transfer from the A bus to the B bus, or from the B bus to the A bus, depending on the logic levels of the enable inputs (GBA and GAB). The enable inputs can be used to disable the devices, effectively isolating the buses. The dual-enable configuration allows the quadruple bus transceivers to store data by simultaneously enabling GBA and GAB. In this transceiver configuration, each output reinforces its input. Therefore, when both control inputs are enabled and all other data sources on both sets of bus lines are in a high-impedance state, both sets of bus lines (8 lines total) will retain their states. For the 'ALS242 and AS242, the 4-bit codes appearing on the two sets of buses will be complementary; for the 'ALS243 and AS243, they will be identical. The -1 versions of the SN74ALS series are identical to the standard versions except that the recommended maximum IOL is increased to 48 mA. There are no -1 versions of the SN54ALS series. The SN54 series is suitable for the full operating temperature range of -55°C to 125°C. The SN74 series is suitable for an operating temperature range of 0°C to 70°C.

• PNP inputs reduce loading
• Package options include plastic "small outline," ceramic chip carrier, and standard plastic and ceramic 300-mil DIP packages
• Reliable Texas Instruments quality and dependability

• Bidirectional asynchronous communication between data buses