SA33C-B Equivalent & Substitute Parts

Part Overview

The SA33C-B is a transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for telecom applications. This bidirectional Zener diode operates in the DO-204AC (DO-15) axial through-hole package and provides transient voltage protection with a 33V reverse standoff voltage and 53.3V maximum clamping voltage at peak pulse current.

The SA33C-B is classified as obsolete. Locating equivalent or substitute components is necessary to support ongoing maintenance, repair, and new design requirements where this part is specified or functionally required.

Substiute Parts

SA33C-B

Littelfuse Inc.In Stock: 880SA33C-B Datasheet

Current PartRFQ

SA33CA

Fairchild SemiconductorIn Stock: 13784SA33CA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SA33C-B is determined by electrical and mechanical parameter equivalence within the TVS diode category. The following parameters establish substitution validity:

Critical Electrical Parameters:

• Voltage - Reverse Standoff (Typ): 33V
• Voltage - Breakdown (Min): 36.7V
• Voltage - Clamping (Max) @ Ipp: 53.3V
• Current - Peak Pulse (10/1000µs): 9.6A
• Power - Peak Pulse: 500W
• Bidirectional Channels: 1
• Type: Zener

Critical Mechanical Parameters:

• Mounting Type: Through Hole
• Package / Case: DO-204AC (DO-15), Axial

Compliance Parameters:

• RoHS Status: RoHS Compliant or equivalent

The SA33CA meets all critical electrical and mechanical parameters and is therefore classified as a direct equivalent substitute for the SA33C-B.

Parameter Comparison

Engineering Selection Recommendations

The SA33CA is a direct electrical and mechanical equivalent to the SA33C-B. Both components are classified as obsolete products and share identical electrical specifications across all critical parameters: 33V reverse standoff voltage, 36.7V minimum breakdown voltage, 53.3V maximum clamping voltage, 9.6A peak pulse current, and 500W peak pulse power rating.

Both parts are packaged in the DO-204AC (DO-15) axial through-hole configuration and are suitable for identical circuit applications. The SA33CA maintains RoHS3 compliance, meeting current environmental and regulatory standards.

The primary consideration is the operating temperature range. The SA33C-B supports -65°C to 175°C, while the SA33CA supports -55°C to 175°C. In applications requiring operation below -55°C, the SA33C-B provides extended low-temperature capability. For applications within the -55°C to 175°C range, the SA33CA functions as a complete substitute.

Both components are obsolete; availability through authorized distributors should be verified prior to procurement.

Frequently Asked Questions (FAQ)

Q: Can the SA33CA directly replace the SA33C-B in existing designs?

A: The SA33CA is electrically and mechanically equivalent to the SA33C-B across all critical TVS diode parameters. Direct substitution is valid for applications operating within the -55°C to 175°C temperature range. Applications requiring operation below -55°C require the SA33C-B due to its extended low-temperature rating of -65°C.

Q: Are there package compatibility concerns between SA33C-B and SA33CA?

A: Both components use the DO-204AC (DO-15) axial through-hole package. Physical dimensions, lead spacing, and mounting characteristics are identical. No package-related modifications are required for substitution.

Q: What is the significance of the different manufacturers?

A: The SA33C-B is manufactured by Littelfuse Inc., while the SA33CA is manufactured by Fairchild Semiconductor. Both manufacturers produce components meeting the same electrical and mechanical specifications. Manufacturer differences do not affect functional equivalence when specifications are identical.

Q: How do RoHS compliance levels affect substitution?

A: The SA33C-B carries RoHS Compliant status, while the SA33CA carries ROHS3 Compliant status. ROHS3 represents a more recent compliance standard. Both statuses indicate environmental and regulatory compliance. The SA33CA meets current compliance requirements.

Q: Are both parts currently available?

A: Both the SA33C-B and SA33CA are classified as obsolete products. Availability is limited to existing inventory held by authorized distributors. Procurement timelines may be extended due to obsolescence status.

Q: What electrical parameters must match for substitution validity?

A: Substitution validity requires equivalence in reverse standoff voltage (33V), breakdown voltage (36.7V minimum), clamping voltage (53.3V maximum), peak pulse current (9.6A), and peak pulse power (500W). All these parameters are identical between the SA33C-B and SA33CA.