74HC4351DB,118

Overview

The Nexperia 74HC4351DB,118 is an 8-channel analog multiplexer/demultiplexer with address latches in a SO20 package. It operates as a single-pole octal-throw switch with three digital select inputs (S0 to S2), eight independent I/Os (Yn), and one common I/O (Z). The device supports dual supplies: VCC ranges from 2.0 V to 10.0 V for HC and 4.5 V to 5.5 V for HCT; VEE ranges from -10.0 V to 0 V. ON resistance is typically 80 Ω at 4.5 V supply difference. Propagation delay is max 18 ns at 4.5 V. ESD protection exceeds 2000 V (HBM) and 1000 V (CDM). Operating temperature spans -40 °C to +125 °C.

Feature Summary

• Integrated address latches allow data storage at select inputs via the latch enable pin.
• Built-in logic level translation enables communication between 5 V logic and ±5 V analog signals.
• Typical 'break before make' switching action prevents signal shorting during channel transitions.
• Inputs include clamp diodes to interface with voltages exceeding VCC using current limiting resistors.

Applications

• Analog multiplexing and demultiplexing
• Digital multiplexing and demultiplexing
• Signal gating

Procurement Notes

Verify the ordering suffix ',118' corresponds to the standard tape-and-reel packaging format specified by Nexperia for this part number. Confirm that the 'D' designation strictly indicates the SO20 plastic small outline package variant. Ensure the component matches the Rev. 6 datasheet published on July 25, 2024, to guarantee compliance with current JEDEC standards and ESD specifications.

Selection Notes

Select the 74HC4351DB variant when wide supply voltage flexibility is required, supporting up to 10 V on VCC and negative voltages on VEE. Choose this specific package only if the PCB layout accommodates the SO20 footprint dimensions. Verify that the application requires address latching functionality, as the LE input controls data storage at the select pins. Ensure the analog signal range stays within the -5 V to +5 V limits for optimal performance.

Part Context

This component belongs to the 74HC/HCT4351 family of 8-channel analog switches. It shares functional similarities with the 74HC4353 but offers higher channel density. The 'DB' suffix specifically identifies the SO20 package version, distinct from the PW (TSSOP20) or older SSOP variants which have been removed from recent datasheets. It serves as a core building block for multi-channel data acquisition systems.

Replacement Considerations

Publicly confirmed substitutes include the 74HCT4351D,118 for TTL-compatible logic levels. The 74HC4351PW,118 is available for TSSOP20 package requirements. Cross-reference with the 74HC4353D for triple 2-channel applications if fewer channels suffice. Verify pin compatibility before substitution.

FAQ

How does the latch enable (LE) input function?

When LE is HIGH, the latch is transparent, allowing select inputs to pass through directly. When LE goes LOW, the state of the select inputs is latched, maintaining the selected channel even if S0-S2 change.

What is the purpose of the two enable inputs E1 and E2?

All eight switches are turned off when E1 is HIGH or E2 is LOW. Normal operation requires E1 to be LOW and E2 to be HIGH.

Can the device handle analog signals exceeding VCC?

Yes, inputs include clamp diodes. Current limiting resistors can be used to interface inputs to voltages in excess of VCC, provided the clamping current limits are not exceeded.