SN54HCT623, SN74HCT623
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS

SCLS016B - MARCH 1984 - REVISED MAY 1997

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features

• Inputs Are TTL-Voltage Compatible
• Lock Bus-Latch Capability
• True Logic
• High-Current 3-State Outputs Can Drive up to 15 LSTTL Loads
• Package Options Include Plastic Small-Outline (DW) and Ceramic Flat (W) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs

description

These octal bus transceivers are designed for asynchronous two-way communication between data buses. The control-function implementation allows for maximum flexibility in timing.

The 'HCT623 allow data transmission from the A bus to the B bus or from the B bus to the A bus, depending upon the logic levels at the output-enable (OEAB and ) inputs.

The output-enable inputs disable the device so that the buses are effectively isolated. The dual-enable configuration gives the transceivers the capability to store data by simultaneously enabling OEAB and. Each output reinforces its input in this transceiver configuration. When both OEAB and are enabled and all other data sources to the two sets of bus lines are in the high-impedance state, both sets of bus lines (16 total) remain at their last states. The 8-bit codes appearing on the two sets of buses are identical.

The SN54HCT623 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74HCT623 is characterized for operation from -40°C to 85°C.