SMS15T1 Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The SMS15T1 is a unidirectional Zener-type transient voltage suppressor diode manufactured by onsemi, designed for general-purpose overvoltage protection in surface-mount applications. The device features a 15V reverse standoff voltage with 29V maximum clamping voltage and 12A peak pulse current capability (8/20µs waveform). The SMS15T1 is classified as obsolete product status, necessitating identification of active equivalent and substitute parts for new designs and ongoing production requirements.

Substiute Parts

SMS15T1

onsemiIn Stock: 1329SMS15T1 Datasheet

Current PartRFQ

SMS15T1G

onsemiIn Stock: 4625SMS15T1G 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 of the SMS15T1 is determined by the following critical parameters:

Primary Substitution Criteria:

• Voltage - Reverse Standoff (Typ): 15V nominal
• Voltage - Clamping (Max) @ Ipp: 29V maximum
• Current - Peak Pulse (10/1000µs): 12A (8/20µs)
• Power - Peak Pulse: 350W
• Unidirectional Channels: 4
• Mounting Type: Surface Mount
• Package / Case: SC-74, SOT-457

Direct Equivalent: SMS15T1G (onsemi) is the direct equivalent with identical electrical specifications. The primary difference is product status (Active vs. Obsolete) and RoHS compliance (ROHS3 Compliant vs. RoHS non-compliant).

Similar Substitutes: The BZA420A series (Nexperia USA Inc.) and BZA456A series (Nexperia USA Inc.) are listed as similar alternatives. However, these parts exhibit different voltage and current ratings:

• BZA420A series: 20V reverse standoff, 28V clamping voltage, lower power dissipation (19.6W)
• BZA456A series: 5.6V reverse standoff, 8V clamping voltage, 3A peak pulse current, 24W power dissipation

These alternatives are not electrically equivalent and represent different protection voltage classes. Selection requires circuit-level analysis to confirm compatibility with the intended application.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Electrical Equivalence): SMS15T1G is the recommended substitute for SMS15T1. Both parts maintain identical electrical specifications (15V reverse standoff, 29V clamping voltage, 12A peak pulse current, 350W power dissipation). SMS15T1G offers the advantage of Active product status and ROHS3 compliance, making it suitable for new designs and production environments with RoHS requirements.

For Alternative Protection Voltage Classes: The BZA420A and BZA456A series from Nexperia USA Inc. are not direct electrical equivalents. These parts are suitable only when circuit requirements permit different protection voltage levels:

• BZA420A series (20V standoff, 28V clamping) for applications requiring higher protection thresholds
• BZA456A series (5.6V standoff, 8V clamping) for applications requiring lower protection thresholds

All Nexperia alternatives carry Automotive grade qualification (AEC-Q100) and ROHS3 compliance, with extended operating temperature range (-65°C to 150°C).

Frequently Asked Questions (FAQ)

Q: Can SMS15T1G be used as a direct replacement for SMS15T1? A: Yes. SMS15T1G is electrically identical to SMS15T1 with matching voltage ratings (15V standoff, 29V clamping), current ratings (12A peak pulse), and power dissipation (350W). The primary differences are product status (Active vs. Obsolete) and RoHS compliance (ROHS3 vs. non-compliant).

Q: Are the BZA420A and BZA456A series compatible with SMS15T1 applications? A: No. The BZA420A and BZA456A series have different voltage and current ratings and are not electrically equivalent. BZA420A offers 20V standoff voltage (vs. 15V), and BZA456A offers 5.6V standoff voltage (vs. 15V). These parts are suitable only for applications with different protection voltage requirements.

Q: What is the significance of the different BZA420A and BZA456A part number suffixes (115, 125, 135, 165)? A: The suffixes indicate different manufacturing date codes or tape reel configurations. All variants within each series (BZA420A or BZA456A) maintain identical electrical specifications and are interchangeable from an electrical standpoint.

Q: Does the SMS15T1G maintain the same package footprint as SMS15T1? A: Yes. Both SMS15T1 and SMS15T1G use the SC-74 / SOT-457 surface-mount package, ensuring PCB layout compatibility.

Q: What are the compliance advantages of SMS15T1G over SMS15T1? A: SMS15T1G is ROHS3 compliant, whereas SMS15T1 is RoHS non-compliant. For new designs and production environments subject to RoHS regulations, SMS15T1G is the appropriate selection.

Q: Are the Nexperia BZA420A and BZA456A parts suitable for automotive applications? A: Yes. All Nexperia alternatives carry Automotive grade qualification and AEC-Q100 certification, making them suitable for automotive-grade applications. SMS15T1 and SMS15T1G do not carry automotive qualification.