TPSMA6L22A Equivalent & Substitute Parts

Part Overview

The TPSMA6L22A is an automotive-grade transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc. in the DO-221AC package. This unidirectional Zener diode is designed for surface mount applications requiring transient voltage protection with a 22V reverse standoff voltage and 35.5V maximum clamping voltage. The part is active in production, AEC-Q101 qualified, and ROHS3 compliant. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to inventory constraints, supply chain considerations, or design flexibility needs.

Substiute Parts

TPSMA6L22A

Littelfuse Inc.In Stock: 3993TPSMA6L22A Datasheet

Current PartRFQ

SM4T26AY

STMicroelectronicsIn Stock: 10776SM4T26AY Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TPSMA6L22A is based on the following critical electrical and mechanical parameters:

Voltage Parameters: The reverse standoff voltage (22V typical) and breakdown voltage minimum (24.4V) must remain constant to ensure proper circuit protection thresholds. These parameters define the protection window and cannot be altered.

Clamping Voltage: The maximum clamping voltage at peak pulse current (Ipp) determines the maximum transient voltage the protected circuit will experience. Substitute parts must maintain compatibility within the application's voltage tolerance.

Peak Pulse Current: The peak pulse current rating (16.9A at 10/1000µs) establishes the maximum transient current the device can suppress. Substitute parts with equal or higher current ratings maintain or improve protection capability.

Package and Mounting: Surface mount DO-221AC (SMA) package compatibility is required for PCB layout and assembly process alignment.

Automotive Grade and Qualification: AEC-Q101 qualification and automotive-grade classification ensure reliability in automotive environments and must be maintained in substitute selections.

Temperature Range: Operating temperature range (-50°C ~ 150°C) defines the thermal operating envelope for the application.

Parameter Comparison

Engineering Selection Recommendations

Both the TPSMA6L22A and SM4T26AY maintain identical reverse standoff voltage (22V) and breakdown voltage minimum (24.4V) specifications, establishing equivalent protection thresholds for transient suppression circuits.

The SM4T26AY substitute provides higher peak pulse current capability (48A versus 16.9A) and an extended lower operating temperature limit (-55°C versus -50°C). Both devices maintain automotive-grade classification and AEC-Q101 qualification, ensuring compliance with automotive reliability standards.

Package differences exist between the two devices: the TPSMA6L22A uses DO-221AC with SMA flat leads, while the SM4T26AY uses DO-214AC SMA package. PCB layout and assembly process compatibility must be verified for package substitution.

The clamping voltage differential (35.5V versus 48.3V) indicates different transient voltage response characteristics. Circuit design parameters must accommodate the higher clamping voltage of the substitute part.

Frequently Asked Questions (FAQ)

Q: Can SM4T26AY directly replace TPSMA6L22A in existing PCB designs?

A: Package compatibility must be verified. The TPSMA6L22A uses DO-221AC with SMA flat leads, while SM4T26AY uses DO-214AC SMA package. Physical footprint and lead configuration differences may require PCB layout modifications.

Q: Are the voltage protection thresholds identical between these parts?

A: Yes. Both devices maintain 22V reverse standoff voltage and 24.4V minimum breakdown voltage, providing equivalent protection threshold characteristics.

Q: What is the significance of the different clamping voltages?

A: The TPSMA6L22A clamps at 35.5V maximum, while SM4T26AY clamps at 48.3V maximum. The protected circuit will experience higher transient voltages with the substitute part. Circuit design parameters must accommodate this difference.

Q: Do both parts meet automotive qualification requirements?

A: Yes. Both the TPSMA6L22A and SM4T26AY are automotive-grade devices with AEC-Q101 qualification and ROHS3 compliance.

Q: What is the difference in peak pulse current ratings?

A: The TPSMA6L22A is rated for 16.9A peak pulse current (10/1000µs), while SM4T26AY is rated for 48A peak pulse current (8/20µs). The substitute part provides higher transient current suppression capability.

Q: Are there temperature range differences?

A: The SM4T26AY extends the lower operating temperature limit to -55°C compared to -50°C for the TPSMA6L22A. Both maintain the same upper temperature limit of 150°C.