SA12 Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The SA12 is a unidirectional Zener-type transient voltage suppressor diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. Housed in a DO-204AC (DO-15) axial through-hole package, this component operates across a temperature range of -55°C to 175°C and meets ROHS3 compliance requirements.

The SA12 is classified as obsolete, necessitating identification of functionally equivalent substitute components for ongoing design support and procurement. Suitable alternatives must maintain electrical compatibility across reverse standoff voltage, breakdown voltage, clamping voltage, and peak pulse current specifications while accommodating available packaging options.

Substiute Parts

SA12

Littelfuse Inc.In Stock: 1106SA12 Datasheet

Current PartRFQ

SA12A

Fairchild SemiconductorIn Stock: 2436SA12A Datasheet

DirectRFQ

SA12A-B

Littelfuse Inc.In Stock: 1707SA12A-B Datasheet

MFR RecommendedRFQ

1N6463

Semtech CorporationIn Stock: 9481N6463 Datasheet

MFR RecommendedRFQ

SA12A-AP

Micro Commercial CoIn Stock: 1169SA12A-AP Datasheet

MFR RecommendedRFQ

SA12A-BP

Micro Commercial CoIn Stock: 774SA12A-BP Datasheet

MFR RecommendedRFQ

SA12A-TP

Micro Commercial CoIn Stock: 930SA12A-TP Datasheet

MFR RecommendedRFQ

SAC12-TP

Micro Commercial CoIn Stock: 4938SAC12-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute components for the SA12 are qualified based on the following electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - Reverse Standoff (Typ): 12V (exact match required)
• Voltage - Clamping (Max) @ Ipp: 19.0V to 22.6V (acceptable range for general-purpose protection)
• Current - Peak Pulse (10/1000µs): 22A to 25.6A (within operational tolerance)
• Power - Peak Pulse: 500W (standard rating)
• Mounting Type: Through Hole (mechanical compatibility)
• Package / Case: DO-204AC, DO-15, or Axial (form factor compatibility)

Secondary Considerations:

• Product Status: Active or Obsolete (availability and lifecycle support)
• RoHS Compliance: ROHS3 Compliant (regulatory alignment)
• Operating Temperature Range: -55°C to 175°C (thermal envelope compatibility)

All identified substitutes maintain the 12V reverse standoff voltage specification and operate within the defined clamping voltage and peak pulse current parameters, ensuring functional equivalence for general-purpose transient voltage suppression applications.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: SA12A-B (Littelfuse Inc.)

SA12A-B is the manufacturer-recommended direct replacement for the obsolete SA12. This component maintains Littelfuse manufacturing continuity, carries Active product status, and provides identical electrical performance with 25.6A peak pulse current capability. ROHS3 compliance and MSL 1 rating align with the original specification. The DO-204AC (DO-15) package ensures mechanical compatibility with existing designs.

Secondary Recommendations: SA12A-AP, SA12A-BP, SA12A-TP (Micro Commercial Co)

These variants offer Active product status and identical electrical parameters to SA12A-B (12V standoff, 19.9V clamping, 25.6A peak pulse). Packaging options accommodate both bulk (AP, BP) and tape & reel (TP) procurement methods. Operating temperature range (-55°C to 175°C) matches the original specification. Selection among these variants depends on packaging and supply chain requirements.

Alternative: SAC12-TP (Micro Commercial Co)

SAC12-TP provides Active product status with marginally reduced specifications (19V clamping, 25A peak pulse). This component remains suitable for applications where the reduced clamping voltage and peak pulse current fall within system tolerance margins. Tape & reel packaging supports automated assembly workflows.

Limited Availability: 1N6463 (Semtech Corporation)

1N6463 is discontinued at DiGi Electronics and carries higher clamping voltage (22.6V) and lower peak pulse current (22A) compared to the SA12. This component is suitable only where system design accommodates the elevated clamping voltage and reduced current handling capacity. Extended operating temperature range (-65°C to 175°C) provides thermal margin beyond the original specification.

Frequently Asked Questions (FAQ)

Q: Can SA12A-B directly replace SA12 in existing designs?

A: Yes. SA12A-B maintains the 12V reverse standoff voltage, operates within the acceptable clamping voltage range (19.9V vs. 20.9V), and provides equivalent peak pulse current (25.6A). The DO-204AC package ensures mechanical compatibility. Active product status supports ongoing procurement.

Q: What is the difference between SA12A-AP, SA12A-BP, and SA12A-TP?

A: These variants are electrically identical (12V standoff, 19.9V clamping, 25.6A peak pulse) and differ only in packaging format. SA12A-AP and SA12A-BP are supplied in bulk; SA12A-TP is supplied in tape & reel format. Selection depends on procurement method and assembly requirements.

Q: Is SAC12-TP suitable as a substitute?

A: SAC12-TP is functionally equivalent within defined parameters (12V standoff, 19V clamping, 25A peak pulse). The reduced clamping voltage and peak pulse current are acceptable for applications where system design margins accommodate these specifications. Active product status ensures availability.

Q: Why does 1N6463 have higher clamping voltage than SA12?

A: 1N6463 exhibits 22.6V clamping voltage compared to SA12's 20.9V. This characteristic is inherent to the Semtech design and must be evaluated against system overvoltage protection requirements. The component is suitable only where elevated clamping voltage does not compromise protected circuit integrity.

Q: Are all substitutes ROHS3 compliant?

A: SA12A-B, SA12A-TP, and SAC12-TP carry explicit ROHS3 compliance certification. SA12A-AP and SA12A-BP do not specify RoHS status in available documentation. 1N6463 and SA12A (Fairchild) do not specify RoHS status. Regulatory compliance verification is required for applications subject to RoHS requirements.

Q: What is the operating temperature range for each substitute?

A: SA12A-B, SA12A-AP, SA12A-BP, and SA12A-TP operate across -55°C to 175°C, matching the original SA12 specification. SAC12-TP operates across -55°C to 175°C. 1N6463 provides extended range (-65°C to 175°C). SA12A (Fairchild) does not specify operating temperature range.

Q: Can I use axial-only packages (1N6463) in designs requiring DO-15 compatibility?

A: 1N6463 is supplied only in axial package format. Designs requiring DO-15 package compatibility must select from SA12A-B, SA12A-AP, SA12A-BP, SA12A-TP, or SAC12-TP, which support both DO-15 and axial configurations.