74AC648SCX Equivalent & Substitute Parts

Part Overview

The 74AC648SCX is a non-inverting transceiver IC manufactured by onsemi, designed for 8-bit data transmission with 3-state output capability. This component operates across a 2V to 6V supply voltage range and is housed in a 24-SOP package. The part is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and component procurement.

Substiute Parts

74AC648SCX

onsemiIn Stock: 84474AC648SCX Datasheet

Current PartRFQ

MC74AC646DWR2G

onsemiIn Stock: 22179MC74AC646DWR2G Datasheet

Parametric EquivalentRFQ

MC74AC652DWR2G

onsemiIn Stock: 767MC74AC652DWR2G Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 74AC648SCX is determined by strict alignment of the following electrical and mechanical parameters:

• Logic Type: Transceiver, Non-Inverting
• Number of Elements: 1
• Number of Bits per Element: 8
• Output Type: 3-State
• Current - Output High, Low: 24mA, 24mA
• Voltage - Supply: 2V ~ 6V
• Operating Temperature: -40°C ~ 85°C (TA)
• Package / Case: 24-SOIC (0.295", 7.50mm Width)
• Mounting Type: Surface Mount
• Series: 74AC

The identified substitute parts MC74AC646DWR2G and MC74AC652DWR2G meet all critical electrical specifications and package requirements. Both alternatives are manufactured by onsemi and maintain functional equivalence within the 74AC logic family.

Parameter Comparison

Engineering Selection Recommendations

Both MC74AC646DWR2G and MC74AC652DWR2G are valid substitutes for the 74AC648SCX based on electrical and mechanical parameter equivalence. The substitute parts carry ROHS3 compliance certification, whereas the original part does not specify RoHS status. Both substitute parts are classified as obsolete, consistent with the original component status.

The primary distinction between the substitutes lies in moisture sensitivity level: the 74AC648SCX carries MSL 1 (unlimited), while both alternatives carry MSL 3 (168 hours). This difference affects storage and handling requirements but does not impact electrical functionality or circuit performance.

Frequently Asked Questions (FAQ)

Q: Can MC74AC646DWR2G and MC74AC652DWR2G be used interchangeably with 74AC648SCX?

A: Yes. Both parts meet all specified electrical parameters (voltage supply, output current, operating temperature) and package requirements (24-SOIC, surface mount). Functional equivalence is established through parameter alignment within the 74AC logic family.

Q: What is the significance of the different MSL ratings?

A: Moisture Sensitivity Level (MSL) determines storage and handling conditions prior to soldering. MSL 1 allows unlimited shelf life, while MSL 3 requires storage below 30°C and 85% relative humidity with a 168-hour floor life limit after bag opening. This affects component procurement and warehouse management but does not alter circuit performance.

Q: Are there package compatibility concerns?

A: No. All three parts use the 24-SOIC package with identical dimensions (0.295", 7.50mm width). PCB footprints and assembly processes remain unchanged.

Q: Why is RoHS compliance relevant for obsolete parts?

A: ROHS3 compliance on the substitute parts indicates adherence to current environmental and hazardous substance restrictions. This may be relevant for systems subject to regulatory compliance requirements or long-term supply chain planning.

Q: What is the base product number difference between substitutes?

A: The 74AC648SCX has base product number 74AC648, while MC74AC646DWR2G has base number 74AC646 and MC74AC652DWR2G has base number 74AC652. These designations reflect internal onsemi product line organization but do not affect functional equivalence for this application.