Is there a pin-compatible replacement for B4B-XH-A-G?

While candidates like ZX-XH2.54-4PZZ-Y appear to be pin-compatible based on datasheet parameters, a full mechanical drawing comparison is required to confirm a direct drop-in replacement for the JST B4B-XH-A-G.

What risks should I check before replacing B4B-XH-A-G?

The main risks involve mechanical fit and electrical ratings. Ensure the substitute's dimensions (shroud height, pin length) match your PCB layout. Also, confirm the voltage and current ratings are at least 250V and 3A, as some generic alternatives may have lower specifications.

B4B-XH-A-G Alternatives, Datasheet & Cross Reference | JST

The JST B4B-XH-A-G is a popular 4-pin, 2.5mm pitch straight header. Several form-fit-function alternatives exist from other manufacturers, but require verification of mechanical dimensions and electrical ratings.

AI replacement insight

Package riskmedium

Requires datasheet review for mechanical dimensions to ensure PCB fit.

Electrical risklow

Low if ratings are confirmed to be >= 3A/250V from a reliable datasheet.

Can it be replaced directly?

No direct drop-in replacement is confirmed without a detailed comparison of mechanical drawings. However, several candidates are strong functional and form-factor matches.

Best replacement path

Cross-vendor alternatives from the XH connector family, such as Megastar ZX-XH2.54-4PZZ-Y or DEALON XH-4PS, offer the most promising path, pending mechanical verification.

Main risk

Mechanical incompatibility due to subtle differences in shroud dimensions or pin length, even with the same pitch and pin count.

Recommended alternatives

A 4-pin, 2.5mm pitch straight header with matching electrical ratings; requires mechanical verification.

View details

Alternative comparison matrix

Feature / factor	B4B-XH-A-G	XH-4PS	ZX-XH2.54-4PZZ-Y	Compatibility / risk
Positions	4	4	4	4 — Matched; ZX-XH2.54-4PZZ-Y: Matched
Pitch	2.5mm	2.5mm	2.5mm	2.5mm — Matched; ZX-XH2.54-4PZZ-Y: Matched
Package	Through Hole, Straight	Through Hole, Straight	Through Hole, Straight	Through Hole, Straight — Orientation matches target.; ZX-XH2.54-4PZZ-Y: Orientation matches target.
Current	3A	3A	3A	3A — Matched; ZX-XH2.54-4PZZ-Y: Matched
Voltage	250V	250V	250V	250V — Matched; ZX-XH2.54-4PZZ-Y: Matched

Application & sourcing insights

Questions & answers

Several manufacturers like Megastar and DEALON offer connectors like ZX-XH2.54-4PZZ-Y and XH-4PS that match key specifications such as pin count, pitch, and ratings. However, verifying the datasheet for precise mechanical dimensions is crucial before substitution.