WHD16027G 10/100BASE-TX LAN Transformer

The WHD16027G is a through-hole part, so the drawing gives a wave-soldering profile rather than a reflow profile.

Preheat dwells at 100–110 °C and the solder peak is 255–265 °C, held for 3.0–5.0 s. These parameters are not interchangeable with a reflow profile: the part sees a different thermal history from the surface-mount parts in the 10/100 BASE-T range. Where one board carries both, each process is set from its own curve.

Assembly process first, board area second.

The WHD16027G is through-hole on a 20.30 × 9.70 mm body with a 2.54 mm terminal pitch, requiring drilled holes and a wave-solder pass; the equivalent surface-mount parts are 12.80 × 6.90 mm on a 1.27 mm pitch and go through reflow. On a line that has gone fully surface-mount, opening a wave pass for one part rarely pays; on an established platform where serviceability matters, through-hole still has its place. Both are listed in the 10/100 BASE-T range.

Cabinets, equipment rooms and indoor equipment that are air-conditioned or at least shielded from outdoor temperature.

0 °C to +70 °C is the commercial grade, covering room ambient plus internal rise. Outdoor enclosures, unheated plant floors and DIN-rail industrial gear fall outside it, and need a wide-temperature grade from the 10/100 BASE-T range. The WHD16027G separately states a wider storage range, but that governs unpowered storage only and cannot be used to relax the operating condition.