SMS12CT1G Equivalent & Substitute Parts

Part Overview

The SMS12CT1G is a unidirectional transient voltage suppressor (TVS) diode manufactured by onsemi, designed for general-purpose overvoltage protection in surface-mount applications. This component features a 12V reverse standoff voltage with a 23V clamping voltage and 15A peak pulse current capability in a 6-TSOP package. The part is currently listed as obsolete, making equivalent substitutes necessary for ongoing design support and procurement.

Substiute Parts

SMS12CT1G

onsemiIn Stock: 10389SMS12CT1G Datasheet

Current PartRFQ

PESD12VS5UD,115

Nexperia USA Inc.In Stock: 16931PESD12VS5UD,115 Datasheet

SimilarRFQ

SMS12C.TCT

SemtechIn Stock: 16068SMS12C.TCT Datasheet

SimilarRFQ

SP0505BAHTG

Littelfuse Inc.In Stock: 157275SP0505BAHTG Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SMS12CT1G is determined by the following critical parameters:

Primary Matching Criteria:

• Reverse standoff voltage: 12V (Max)
• Unidirectional channel configuration: 5 channels
• Package type: 6-TSOP or equivalent surface-mount form factor
• Clamping voltage range: 23V ± tolerance
• Peak pulse current: minimum 10A (8/20µs)
• RoHS3 compliance

Substitute Classification:

Group 1 - Direct Functional Equivalents:

• PESD12VS5UD,115 (Nexperia): Matches 12V standoff, 5 channels, 6-TSOP package. Clamping voltage 24V, peak current 10A. Active product status with AEC-Q100 automotive qualification.
• SMS12C.TCT (Semtech): Identical 12V standoff, 5 channels, 23V clamping voltage, 15A peak current. Active product in SMS series. SOT-23-6 package.

Group 2 - Voltage-Incompatible Substitute:

• SP0505BAHTG (Littelfuse): 5.5V reverse standoff voltage with 8.5V clamping voltage. Not suitable for 12V protection circuits due to significantly lower voltage ratings.

Parameter Comparison

Engineering Selection Recommendations

Recommended Primary Substitute: SMS12C.TCT (Semtech)

The SMS12C.TCT provides the closest electrical and mechanical match to the SMS12CT1G. It maintains identical voltage specifications (12V standoff, 13.3V breakdown, 23V clamping), matching peak pulse current (15A), and equivalent power dissipation (300W). The SOT-23-6 package is mechanically compatible with the original 6-TSOP footprint. The part is active in production with ROHS3 compliance, ensuring long-term availability and supply chain stability.

Secondary Substitute: PESD12VS5UD,115 (Nexperia)

The PESD12VS5UD,115 is suitable where slightly reduced peak current capacity (10A versus 15A) and lower peak pulse power (200W versus 350W) are acceptable. This part offers extended operating temperature range (-65°C to 150°C) and AEC-Q100 automotive qualification, making it appropriate for automotive or high-reliability applications. The SC-74/SOT-457 package requires PCB layout verification for mechanical compatibility.

Not Recommended: SP0505BAHTG (Littelfuse)

The SP0505BAHTG operates at 5.5V reverse standoff with 8.5V clamping voltage, making it unsuitable for circuits designed for 12V protection. Substitution would result in inadequate overvoltage suppression and potential component damage.

Frequently Asked Questions (FAQ)

Q: Can the SMS12CT1G be directly replaced with the PESD12VS5UD,115?

A: Yes, with design verification. Both parts share the same 12V reverse standoff voltage and 5-channel unidirectional configuration. However, the PESD12VS5UD,115 has lower peak pulse current (10A versus 15A) and power dissipation (200W versus 350W). Confirm that your circuit's transient energy does not exceed 200W. Package footprints differ (SC-74 versus TSOT-23-6), requiring PCB layout adjustment.

Q: Is the SMS12C.TCT a pin-for-pin replacement?

A: The SMS12C.TCT maintains the same 6-pin SOT-23-6 configuration and electrical specifications as the SMS12CT1G. Pin assignments are compatible for direct substitution. Verify package dimensions (SOT-23-6 versus TSOT-23-6 thin variant) against your PCB layout to confirm mechanical fit.

Q: Why is the SP0505BAHTG listed as a substitute if it has different voltage ratings?

A: The SP0505BAHTG is included in the substitute list but is not electrically compatible with the SMS12CT1G due to its 5.5V standoff voltage. It is suitable only for circuits requiring lower voltage protection (5V nominal systems). Do not use this part as a replacement for 12V protection applications.

Q: What is the difference between the operating temperature ranges?

A: The SMS12CT1G specifies junction temperature (TJ) of -40°C to 150°C, while the PESD12VS5UD,115 specifies ambient temperature (TA) of -65°C to 150°C. The PESD12VS5UD,115 offers a wider ambient temperature range, beneficial for extreme environment applications. The SMS12C.TCT operates at -55°C to 125°C (TJ), providing a narrower high-temperature limit.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. The SMS12CT1G, PESD12VS5UD,115, SMS12C.TCT, and SP0505BAHTG are all ROHS3 compliant, meeting environmental and regulatory requirements for commercial and industrial applications.

Q: What packaging formats are available for these TVS diodes?

A: The SMS12CT1G and SMS12C.TCT are supplied in Tape & Reel (TR) packaging. The PESD12VS5UD,115 is available in Cut Tape (CT) and Digi-Reel® formats. The SP0505BAHTG is supplied in Cut Tape (CT) and Digi-Reel® formats. Verify packaging availability with your supplier for production requirements.