Is there a pin-compatible replacement for SMBJ43CA?

Yes, parts like SMBJ45CA and SMBJ48CA are pin-compatible as they use the same SMB (DO-214AA) package. However, their electrical parameters differ, so they are not direct drop-in replacements without review.

What risks should I check before replacing SMBJ43CA?

Key risks include: 1) A higher standoff voltage (e.g., 45V or 48V) may not protect your circuit adequately. 2) A lower peak pulse current rating reduces surge survivability. 3) Ensure the replacement is also bidirectional.

SMBJ43CA Alternatives, Datasheet & Cross Reference | BOURNS

Finding a substitute for the SMBJ43CA TVS diode requires matching its 43V standoff voltage, bidirectional polarity, and 600W power rating in an SMB package. Alternatives exist but may have different voltage or current ratings.

AI replacement insight

Electrical riskmedium

Substitutes have higher standoff voltages and lower current ratings.

Package risklow

Several candidates share the same SMB (DO-214AA) package.

Firmware risklow

This is a passive protection device with no firmware interaction.

Can it be replaced directly?

No direct, 1-for-1 replacement is identified. Alternatives like SMBJ45CA are parametrically similar but require engineering validation due to differences in standoff voltage and peak current.

Best replacement path

The best path is to use a TVS diode from the same SMBJ series with the closest possible standoff voltage, such as SMBJ45CA, while carefully evaluating the impact of its slightly lower current rating.

Main risk

The main risk is using a substitute with a higher standoff voltage, which reduces the level of overvoltage protection for the downstream circuit.

Recommended alternatives

A parametric alternative in the same SMB package with a slightly higher standoff voltage and lower peak current.

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Alternative comparison matrix

Feature / factor	SMBJ43CA	SMBJ45CA	SMBJ48CA	Compatibility / risk
Package	DO-214AA (SMB)	SMB (DO-214AA)	DO-214AA (SMB)	SMB (DO-214AA) / DO-214AA (SMB) — Package is form-fit compatible.; SMBJ48CA: Package is form-fit compatible.
Polarity Or Type	Bidirectional	Bidirectional	Bidirectional	Bidirectional — Polarity matches the target.; SMBJ48CA: Polarity matches the target.
Voltage V	43V	45V	48V	45V / 48V — Slightly higher standoff voltage reduces protection margin.; SMBJ48CA: Higher standoff voltage significantly reduces protection margin.
Current A	8.7A	8.3A	7.8A	8.3A / 7.8A — Slightly lower peak pulse current rating.; SMBJ48CA: Lower peak pulse current rating reduces surge capability.
Power W	600W	600W	600W	600W — Power rating is identical.; SMBJ48CA: Power rating is identical.

Application & sourcing insights

Questions & answers

The SMBJ45CA is a close parametric alternative. It shares the same package and power rating but has a slightly higher standoff voltage (45V) and lower peak current (8.3A). Engineering review is recommended.