WHS40005G 10/100BASE-TX LAN Transformer

Operating temperature only: the WHS40005G is rated 0 °C to +70 °C and the WHS40005TG -40 °C to +85 °C.

Everything else matches — body, height, pitch and span value for value, the same definition of all 40 terminals, the same internal structure, every electrical item stated identically, and the same 400 pcs per reel. The choice reduces to one question: can the component environment fall below 0 °C or rise above +70 °C? If it can, take the wide-temperature part; if not, the standard one.

Eight, matching four 100M ports.

A 100M port occupies two channels forming one pairset, so a quad-port 100M part holds 4 × 2 = 8 units, where a quad-port Gigabit part holds 16. That count is the most direct way to confirm the data rate: a 40-pin quad-port part with only eight units is a 100M part. Each port on the WHS40005G also carries its own common-mode ground terminal, not shared between ports.

The quad part uses less board and less routing, at the cost of tying four ports to one component.

One WHS40005G covers four 100M ports on a 28.00 × 12.00 mm body; four separate 16-pin single-port parts already match that in body area alone, and adding four sets of keep-out and routing clearance makes the real footprint larger. What it costs is flexibility: port counts that are not multiples of four waste capacity, and a layout constraint on any one port moves the whole component. Both styles are listed in the 10/100 BASE-T range.