74LVC646ADB,118

Overview

The 74LVC646ADB,118 is an octal bus transceiver and register featuring 3-state outputs. It integrates D-type flip-flops with control circuitry for multiplexed data transmission between internal registers. The device supports direct interface with TTL levels and operates within a supply voltage range of 1.2 V to 3.6 V. It provides 5 V tolerant inputs and outputs for interfacing with 5 V logic systems. The component includes separate controls for data flow direction and supports partial power-down applications where inputs and outputs remain high-impedance when VCC is 0 V.

Feature Summary

• Octal bus transceiver with integrated D-type latch functionality
• Back-to-back registers enabling storage and real-time transparent mode multiplexing
• 5 V tolerant I/Os allowing safe interfacing with mixed 3.3 V and 5 V logic systems
• Supports partial power-down modes with high-impedance states during zero supply voltage

Applications

• Mixed voltage translation between 3.3 V and 5 V logic domains
• Multiplexed data transmission using back-to-back register storage
• Partial power-down system architectures requiring high-impedance isolation

Procurement Notes

Verify the package designation 'ADB' corresponds to the SSOP24 (SOT340-1) variant as specified in the ordering information table. Confirm that the temperature range requirement aligns with the -40 °C to +125 °C specification listed for this part number. Ensure compatibility with JEDEC standards JESD8-7A, JESD8-5A, and JESD8-C/JESD36 for the intended operating voltage range.

Selection Notes

Select this component when an octal bidirectional bus interface with internal storage is required. It is suitable for designs needing independent direction control and selectable data sources from either real-time inputs or stored registers. The 5 V tolerance feature makes it appropriate for bridging different voltage logic families without additional level shifting components.

Part Context

This part belongs to the 74LVC series of low-voltage CMOS logic devices manufactured by NXP USA Inc. The 'ADB' suffix indicates the specific SSOP24 plastic shrink small outline package with a body width of 5.3 mm. It shares functional characteristics with other LVC646 variants but differs in physical packaging dimensions and lead configuration.

Replacement Considerations

Consult official documentation for equivalent parts such as 74LVC646AD or 74LVC646APW if package changes are acceptable.