SA17C-B Equivalent & Substitute Parts

Part Overview

The SA17C-B is a transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for telecom applications. This bidirectional zener diode provides transient protection with a 17V reverse standoff voltage and 27.6V maximum clamping voltage. The part is classified as obsolete, necessitating identification of active equivalent components that maintain electrical and mechanical compatibility for continued system support and new designs.

Substiute Parts

SA17C-B

Littelfuse Inc.In Stock: 1028SA17C-B Datasheet

Current PartRFQ

SA17CA

EIC SEMICONDUCTOR INC.In Stock: 4290SA17CA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SA17C-B is determined by strict equivalence across the following critical electrical parameters:

• Voltage - Reverse Standoff (Typ): 17V
• Voltage - Breakdown (Min): 18.9V
• Voltage - Clamping (Max) @ Ipp: 27.6V
• Power - Peak Pulse: 500W
• Operating Temperature Range: -65°C ~ 175°C (TJ)
• Bidirectional Channels: 1
• Type: Zener
• Mounting Type: Through Hole

The SA17CA meets all critical electrical specifications and operates within the same temperature range. Both components are single-channel bidirectional zener TVS diodes with identical voltage ratings and power dissipation capabilities. The primary difference is the package variant: SA17C-B uses DO-204AC (DO-15) while SA17CA uses DO-204AL (DO-41). Both are axial through-hole packages suitable for PCB mounting.

Parameter Comparison

Engineering Selection Recommendations

The SA17CA is an active equivalent substitute for the obsolete SA17C-B. Both components satisfy identical electrical specifications for voltage clamping, breakdown characteristics, and power dissipation. The SA17CA maintains full compliance with current RoHS3 standards and offers superior long-term availability through active product status.

The peak pulse current specification differs marginally: SA17C-B specifies 18.5A while SA17CA specifies 18.1A. This 0.4A variance remains within acceptable tolerance for transient suppression applications and does not compromise circuit protection performance.

Package compatibility requires attention: the SA17C-B uses DO-204AC (DO-15) while SA17CA uses DO-204AL (DO-41). Both are axial through-hole packages with similar physical dimensions suitable for standard PCB layouts. PCB footprint verification is necessary prior to implementation to confirm lead spacing and hole diameter compatibility with existing designs.

Frequently Asked Questions (FAQ)

Q: Can SA17CA directly replace SA17C-B without PCB modification?

A: Electrical substitution is direct. Physical substitution requires PCB footprint verification. Both components are axial through-hole packages, but DO-204AC (DO-15) and DO-204AL (DO-41) have different lead spacing. Existing PCB holes may require adjustment or the component may require lead bending to accommodate different pitch.

Q: What is the significance of the 0.4A difference in peak pulse current?

A: SA17C-B specifies 18.5A peak pulse current while SA17CA specifies 18.1A. This variance is within normal manufacturing tolerance for TVS diodes and does not affect transient suppression capability for standard telecom applications. Both components dissipate 500W peak power.

Q: Are there compliance differences between SA17C-B and SA17CA?

A: SA17C-B is RoHS Compliant. SA17CA is ROHS3 Compliant, representing current regulatory compliance. Both components have MSL rating of 1 (Unlimited), indicating no moisture sensitivity restrictions. SA17CA includes REACH status information available upon request.

Q: Why is SA17C-B classified as obsolete?

A: Littelfuse Inc. has discontinued the SA17C-B. The SA17CA from EIC SEMICONDUCTOR INC. maintains identical electrical specifications and serves as the active equivalent for continued system support and new designs.

Q: What applications are supported by these TVS diodes?

A: SA17C-B is specified for telecom applications. SA17CA is designated for general purpose applications. Both components function identically as bidirectional transient voltage suppressors for circuit protection in the 17V to 27.6V operating range.

Q: Are there inventory considerations for component selection?

A: SA17C-B inventory is limited to existing stock (1012 pcs). SA17CA is actively manufactured with higher available inventory (4241 pcs), ensuring supply continuity for production requirements.