CY74FCT543ATQCT

The ’FCT543T octal latched transceivers contain two sets of eight D-type latches with separate latch-enable (LEAB, LEBA) and output-enable (OEAB, OEBA) inputs for each set to permit independent control of input and output in either direction of data flow. For data flow from A to B, for example, the A-to-B enable (CEAB) input must be low in order to enter data from A or to take data from B, as indicated in the function table. With CEAB low, a low signal on the A-to-B latch-enable (LEAB) input makes the A-to-B latches transparent; a subsequent low-to-high transition of the LEAB signal puts the A latches in the storage mode and their outputs no longer change with the A inputs. With CEAB and OEAB low, the 3-state B-output buffers are active and reflect the data present at the output of the A latches. Control of data from B to A is similar, but uses CEBA, LEBA, and OEBA inputs. These devices are fully specified for partial-power-down applications using Ioff. The I(off) circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.

Key features

• Function, Pinout, and Drive Compatible With FCT and F Logic
• Reduced V₀ₕ (Typically = 3.3 V) Versions of Equivalent FCT Functions
• Edge-Rate Control Circuitry for Significantly Improved Noise Characteristics
• Ioff Supports Partial-Power-Down Mode Operation
• Matched Rise and Fall Times
• Fully Compatible With TTL Input and Output Logic Levels
• 3-State Outputs
• ESD Protection Exceeds JESD 22:
• 2000-V Human-Body Model (A114-A)
• 200-V Machine Model (A115-A)
• 1000-V Charged-Device Model (C101)
• Separation Controls for Data Flow in Each Direction
• Back-to-Back Latches for Storage
• CY54FCT543T:
• 48-mA Output Sink Current
• 12-mA Output Source Current
• CY74FCT543T:
• 64-mA Output Sink Current
• 32-mA Output Source Current