MMQA18VT1 Equivalent & Substitute Parts

Part Overview

The MMQA18VT1 is a transient voltage suppressor (TVS) diode manufactured by onsemi, designed for general-purpose overvoltage protection in surface-mount applications. This component features a 14V reverse standoff voltage with a 26V clamping voltage and 923mA peak pulse current capability in an SC-74 package. The MMQA18VT1 is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. The active equivalent MMQA18VT1G provides identical electrical performance with improved availability and RoHS3 compliance.

Substiute Parts

MMQA18VT1

onsemiIn Stock: 9788MMQA18VT1 Datasheet

Current PartRFQ

MMQA18VT1G

onsemiIn Stock: 47372MMQA18VT1G Datasheet

DirectRFQ

BZA420A,115

Nexperia USA Inc.In Stock: 12207BZA420A,115 Datasheet

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BZA420A,125

Nexperia USA Inc.In Stock: 7007BZA420A,125 Datasheet

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BZA420A,135

Nexperia USA Inc.In Stock: 813BZA420A,135 Datasheet

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BZA420A,165

Nexperia USA Inc.In Stock: 1236BZA420A,165 Datasheet

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BZA456A,115

Nexperia USA Inc.In Stock: 15343BZA456A,115 Datasheet

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BZA456A,125

Nexperia USA Inc.In Stock: 836BZA456A,125 Datasheet

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BZA456A,135

Nexperia USA Inc.In Stock: 11108BZA456A,135 Datasheet

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BZA456A,165

Nexperia USA Inc.In Stock: 11152BZA456A,165 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the MMQA18VT1 is determined by the following critical parameters:

Direct Equivalent (Packaging Variant):

• MMQA18VT1G: Identical electrical specifications with Tape & Reel packaging. This is the active production equivalent with RoHS3 compliance.

Similar Performance Alternatives (Different Voltage Ratings):

• BZA420A series (BZA420A,115 / BZA420A,125 / BZA420A,135 / BZA420A,165): 20V reverse standoff, 28V clamping voltage, 6-TSOP package. Higher voltage rating suitable for applications requiring increased protection margin.
• BZA456A series (BZA456A,115 / BZA456A,125 / BZA456A,135 / BZA456A,165): 5.6V reverse standoff, 8V clamping voltage, 6-TSOP package. Lower voltage rating for reduced-voltage protection circuits.

Substitution eligibility is based on matching or exceeding the reverse standoff voltage, clamping voltage, and peak pulse current requirements of the target application. Package differences (SC-74 vs. 6-TSOP) require PCB layout verification.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: MMQA18VT1G The MMQA18VT1G is the direct equivalent of the obsolete MMQA18VT1, offering identical electrical performance with active product status and RoHS3 compliance. This part maintains the same SC-74 package, reverse standoff voltage (14V), clamping voltage (26V), and peak pulse current (923mA). Selection of MMQA18VT1G eliminates obsolescence risk and satisfies modern regulatory requirements without circuit redesign.

Alternative Selection: BZA420A Series The BZA420A series (available in code variants 115, 125, 135, 165) provides higher voltage protection with 20V reverse standoff and 28V clamping voltage. These parts are suitable for applications requiring increased overvoltage margin. The 6-TSOP package differs from the SC-74, requiring PCB layout modification. All variants carry AEC-Q100 automotive qualification and RoHS3 compliance. Peak pulse current specifications are not provided for this series.

Lower Voltage Alternative: BZA456A Series The BZA456A series (available in code variants 115, 125, 135, 165) is applicable only to circuits designed for 5.6V reverse standoff protection. This series provides 3A peak pulse current and 24W peak pulse power in a 6-TSOP package. Selection requires circuit redesign and is not suitable for direct replacement of the MMQA18VT1 in 14V protection applications.

Frequently Asked Questions (FAQ)

Q: Can MMQA18VT1G be used as a direct replacement for MMQA18VT1? A: Yes. MMQA18VT1G is the active equivalent with identical electrical specifications (14V reverse standoff, 26V clamping, 923mA peak pulse current) and the same SC-74 package. The primary difference is product status (active vs. obsolete) and RoHS3 compliance.

Q: What is the difference between the BZA420A code variants (115, 125, 135, 165)? A: The code variants represent different manufacturing date codes or tape reel configurations. All variants share identical electrical specifications: 20V reverse standoff, 28V clamping voltage, 19.6W peak pulse power, and 6-TSOP package.

Q: Can BZA420A series replace MMQA18VT1 in existing designs? A: BZA420A series can replace MMQA18VT1 only if the application circuit tolerates higher voltage ratings (20V standoff vs. 14V). The 6-TSOP package requires PCB layout changes from the SC-74 footprint. Peak pulse current specifications differ between series.

Q: Is BZA456A suitable for MMQA18VT1 replacement? A: No. BZA456A operates at 5.6V reverse standoff, which is significantly lower than the MMQA18VT1's 14V rating. This series is designed for different voltage protection levels and requires complete circuit redesign.

Q: What compliance certifications apply to substitute parts? A: MMQA18VT1G and all BZA series variants carry RoHS3 compliance. BZA420A and BZA456A series additionally hold AEC-Q100 automotive qualification. The obsolete MMQA18VT1 is RoHS non-compliant.

Q: Does package change affect circuit performance? A: Package change from SC-74 to 6-TSOP affects PCB layout, trace routing, and thermal characteristics. Electrical performance remains equivalent if voltage and current ratings are matched. PCB layout verification is required for package substitution.