DM74ALS646WM Equivalent & Substitute Parts

Part Overview

The DM74ALS646WM is a non-inverting transceiver logic IC manufactured by onsemi, featuring 1 element with 8 bits per element and 3-state output capability. This component operates within the 4.5V to 5.5V supply voltage range and is housed in a 24-SOP package. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations.

Substiute Parts

DM74ALS646WM

onsemiIn Stock: 1867DM74ALS646WM Datasheet

Current PartRFQ

SN74ALS646ADWR

Texas InstrumentsIn Stock: 777SN74ALS646ADWR Datasheet

DirectRFQ

SN74ALS646ADW

Texas InstrumentsIn Stock: 903SN74ALS646ADW Datasheet

Parametric EquivalentRFQ

SN74ALS652A-1DW

Texas InstrumentsIn Stock: 888SN74ALS652A-1DW Datasheet

Parametric EquivalentRFQ

SN74ALS652ADW

Texas InstrumentsIn Stock: 2265SN74ALS652ADW Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DM74ALS646WM is determined by strict equivalence across the following parameters:

• Logic Type: Transceiver, Non-Inverting
• Number of Elements: 1
• Number of Bits per Element: 8
• Output Type: 3-State
• Current - Output High, Low: 15mA, 24mA
• Voltage - Supply: 4.5V ~ 5.5V
• Operating Temperature: 0°C ~ 70°C (TA)
• Mounting Type: Surface Mount
• Package / Case: 24-SOIC (0.295", 7.50mm Width)
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

All identified substitute parts maintain these electrical and mechanical specifications. Packaging format variations (Tape & Reel versus Tube) do not affect functional compatibility.

Parameter Comparison

Engineering Selection Recommendations

All four Texas Instruments substitute parts (SN74ALS646ADWR, SN74ALS646ADW, SN74ALS652A-1DW, SN74ALS652ADW) maintain full electrical and mechanical equivalence to the DM74ALS646WM. The primary distinction lies in product status and regulatory compliance.

The Texas Instruments alternatives are classified as active products with ROHS3 compliance, providing assurance of ongoing availability and regulatory alignment. The DM74ALS646WM, being obsolete, presents supply chain risk for new applications or system refreshes.

Packaging format differences exist only in delivery method: SN74ALS646ADWR is supplied in Tape & Reel format, while SN74ALS646ADW, SN74ALS652A-1DW, and SN74ALS652ADW are supplied in Tube format. These packaging variations do not affect functional performance or pin compatibility.

Frequently Asked Questions (FAQ)

Q: Can SN74ALS646ADWR replace DM74ALS646WM directly?

A: Yes. The SN74ALS646ADWR maintains identical electrical specifications, output characteristics, supply voltage range, operating temperature range, and 24-SOIC package dimensions. The only difference is packaging format (Tape & Reel versus SOP).

Q: What is the difference between SN74ALS646ADW and SN74ALS652ADW?

A: Both parts are parametrically equivalent across all electrical and mechanical specifications provided. The base product numbers differ (74ALS646 versus 74ALS652), but this distinction does not affect functional compatibility in applications designed for the DM74ALS646WM.

Q: Are there any compliance differences between the substitute parts?

A: All Texas Instruments substitutes are ROHS3 compliant and REACH unaffected. The original DM74ALS646WM is REACH unaffected but does not carry ROHS3 certification due to its obsolete status.

Q: Does packaging format (Tape & Reel versus Tube) affect compatibility?

A: No. Packaging format affects only handling, storage, and assembly processes. Electrical performance and pin configuration remain identical across all packaging options.

Q: Why is the DM74ALS646WM classified as obsolete?

A: Obsolescence indicates the manufacturer has discontinued production. Active alternatives from Texas Instruments ensure continued availability for replacement and new design applications.