TPSMC18HE3_A/I Equivalent & Substitute Parts

Part Overview

The TPSMC18HE3_A/I is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Vishay General Semiconductor - Diodes Division. This component is designed for surface mount applications in the DO-214AB (SMC) package and provides transient overvoltage protection with a 14.5V reverse standoff voltage and 26.5V maximum clamping voltage. The part is classified as obsolete, making identification of suitable substitute components essential for ongoing design support and procurement continuity.

Substiute Parts

TPSMC18HE3_A/I

Vishay General Semiconductor - Diodes DivisionIn Stock: 1156TPSMC18HE3_A/I Datasheet

Current PartRFQ

TPSMC18AHE3_B/I

Vishay General Semiconductor - Diodes DivisionIn Stock: 783TPSMC18AHE3_B/I Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TPSMC18HE3_A/I is determined by strict equivalence in the following critical parameters:

Mandatory Matching Criteria:

• Package / Case: DO-214AB (SMC) surface mount package
• Unidirectional Channels: 1 channel configuration
• Type: Zener diode topology
• Mounting Type: Surface mount
• Operating Temperature Range: -65°C ~ 185°C (TJ)
• Grade: Automotive
• Qualification: AEC-Q101

Allowable Parameter Variance:

• Voltage - Reverse Standoff (Typ): ±0.8V tolerance
• Voltage - Breakdown (Min): ±0.9V tolerance
• Voltage - Clamping (Max) @ Ipp: ±1.3V tolerance
• Current - Peak Pulse (10/1000µs): ±3A tolerance
• Power - Peak Pulse: Equal or greater capacity

The TPSMC18AHE3_B/I meets all mandatory matching criteria and falls within allowable parameter variance, qualifying as a direct substitute.

Parameter Comparison

Engineering Selection Recommendations

The TPSMC18AHE3_B/I is qualified as a direct substitute for the obsolete TPSMC18HE3_A/I based on the following engineering factors:

Compliance & Certification: Both parts maintain identical automotive-grade classification and AEC-Q101 qualification, ensuring compatibility with automotive supply chain requirements and quality standards.

Electrical Performance: The TPSMC18AHE3_B/I exhibits parameter variations within acceptable engineering tolerances. The reverse standoff voltage increases by 0.8V, breakdown voltage by 0.9V, and clamping voltage decreases by 1.3V. Peak pulse current capability increases by 2.9A. These variations remain within the functional envelope for transient suppression applications.

Product Status: The substitute part is active and in production, providing procurement continuity and long-term availability compared to the obsolete main part.

Package & Mounting: Identical DO-214AB (SMC) surface mount package ensures direct PCB compatibility without layout modifications.

Frequently Asked Questions (FAQ)

Q: Can TPSMC18AHE3_B/I be used as a direct replacement for TPSMC18HE3_A/I on existing PCBs?

A: Yes. Both parts use the identical DO-214AB (SMC) surface mount package with the same pinout and footprint. No PCB layout changes are required.

Q: What is the significance of the voltage parameter differences?

A: The TPSMC18AHE3_B/I has a higher reverse standoff voltage (15.3V vs. 14.5V) and breakdown voltage (17.1V vs. 16.2V), but a lower clamping voltage (25.2V vs. 26.5V). These differences remain within acceptable tolerances for transient suppression circuits and do not compromise functional performance in typical applications.

Q: Why is the main part listed as obsolete?

A: Obsolescence indicates the part is no longer manufactured or supported by Vishay. The TPSMC18AHE3_B/I, being active and in production, provides a viable path for design continuity and future procurement.

Q: Are there any compliance or certification differences between the two parts?

A: No. Both parts maintain identical automotive-grade classification, AEC-Q101 qualification, ROHS3 compliance, and MSL 1 rating. Compliance requirements are fully satisfied by the substitute part.

Q: Does the packaging differ between these parts?

A: The main part is supplied in standard packaging, while the substitute is supplied in Tape & Reel (TR) format. Both use the DO-214AB (SMC) package. Tape & Reel packaging is standard for high-volume surface mount assembly and does not affect component performance or compatibility.