Is there a pin-compatible replacement for SMAJ85A?

Currently, no pin-compatible replacement has been verified. Known alternatives like the SMBJ series use a different, larger package.

What risks should I check before replacing SMAJ85A?

Verify the PCB can accommodate the larger SMB package. Also, confirm the standoff voltage of the replacement (e.g., 90V or 100V) is compatible with your circuit's maximum operating voltage.

SMAJ85A Alternatives, Datasheet & Cross Reference | Yangjie Technology

SMAJ85A is a 400W TVS diode in an SMA package. Alternatives exist with higher power ratings, but often in a larger SMB package, requiring PCB layout changes and careful voltage compatibility review.

AI replacement insight

Package riskhigh

Alternatives are in a larger SMB package, requiring a PCB layout change.

Electrical risklow

Candidates offer higher power/current, but voltage must be checked.

Can it be replaced directly?

No direct pin-for-pin replacement for SMAJ85A has been identified. Alternatives require board redesign due to different package sizes.

Best replacement path

Functional alternatives like SMBJ90A offer higher power but require a larger PCB footprint (SMB package). No direct pin-compatible upgrade is identified.

Main risk

The primary risk is package incompatibility. Alternatives are in the larger SMB package, not the target's SMA package.

Recommended alternatives

A functional alternative with higher power ratings but in a larger package requiring a board redesign.

View details

Alternative comparison matrix

Feature / factor	SMAJ85A	SMBJ90A	SMBJ100A	Compatibility / risk
Package	SMA (DO-214AC)	SMB (DO-214AA)	SMB (DO-214AA)	SMB (DO-214AA) — Larger footprint, not a drop-in replacement.; SMBJ100A: Larger footprint, not a drop-in replacement.
Voltage	85V	90V	100V	90V / 100V — Slightly higher standoff voltage, generally acceptable.; SMBJ100A: Significantly higher standoff voltage may not protect circuits adequately.
Power	400W	600W	600W	600W — Higher power rating provides more protection.; SMBJ100A: Higher power rating.
Current	2.9A	4.1A	-	4.1A — Higher peak pulse current capability.
Polarity Or Type	Unidirectional	Unidirectional	Unidirectional	Unidirectional — matched; SMBJ100A: matched

Application & sourcing insights

Questions & answers

SMBJ90A is a strong functional alternative with higher power handling (600W), but it comes in a larger SMB package, requiring a board layout change.