WHSG24002GM Gigabit LAN Transformer

Not as a drop-in. The WHSG24002GM specifies a minimum open-circuit inductance of 150 μH against 350 μH for the WHSG24002G, and both are measured under identical conditions. Open-circuit inductance drives the insertion and return loss margin at the low-frequency end, so a difference of more than two to one is not a tolerance to wave through.

The body dimensions, suggested land pattern, pin-to-net assignment and every other electrical figure really are the same on both parts, so the board itself does not change. The link budget, however, has to be recalculated against whichever inductance applies, and a test report for one part cannot be used to sign off the other.

Choose the WHSG24002GM when the component itself has to work across -55 °C to +125 °C. That range is the one thing the WHSG24002GM offers that the other two parts in this package cannot, and it is what the relaxed open-circuit inductance minimum buys. Typical uses are Gigabit ports inside hot enclosures, outdoor equipment in extreme cold, and programmes that need to cite the GJB9001C quality management system, which the datasheet lists as a certification held.

GJB9001C is a management-system standard rather than an environmental or safety rating for the product, so it cannot stand in for equipment-level approval. Where the requirement sits inside -40 °C to +85 °C, the other parts in the 100/1000 BASE-T range keep the higher inductance minimum and are usually the better fit.

Two conditions apply to the WHSG24002GM: +10 °C to +40 °C while the parts are in their original packaging, and -55 °C to +105 °C for the bare components once unpacked. The datasheet splits storage temperature into two separate lines, which is unique within this package family, and which line the warehouse works to depends on whether the reels are still in their original packaging.

The packaged figure is far narrower than the operating range of the part itself. Do not put sealed cartons into cold storage on the grounds that the WHSG24002GM can work at -55 °C; that line constrains the packaging materials and desiccant, not the transformer. Other options are listed in the 100/1000 BASE-T range.