FAQ
Frequently Asked Questions
What is the 18G BASE-T grade, and what parts does it contain?
It is a grade VOOHU defines by the bandwidth a part is specified across — the drawing itself is titled 18G BASE-T — and it currently holds one part.
Its high-frequency specifications extend to 800 MHz, the widest in this catalogue, against 500 MHz for the10G family. The grade name does not correspond to a single named Ethernet data rate, so selection should follow the bands and limits printed on the datasheet rather than an inference from the label. Where a project carries a defined IEEE rate requirement, tell us the target rate and VOOHU will confirm the matching part. The grade is listed in the18G BASE-T range.
How are the high-frequency specifications written in this grade?
Insertion loss, return loss, cross talk and common-mode rejection are each given in three bands rather than as one figure covering the whole range.
The banding follows from the span involved: a limit that holds at low frequency must be relaxed approaching the ceiling. The cross-talk limit in the lowest band is the strictest anywhere in this catalogue, and the part also lists a further common-mode item that no other part here publishes. Align the frequency bands before comparing anything — setting one band of this part against another part's single figure tells you nothing. The datasheet is linked from the18G BASE-T range.
How should the PoE current figures in this grade be read?
The datasheet gives two of them — one current per channel and another for full channels, the second exactly twice the first.
It is the only part in this catalogue that spells out both scopes, and it demonstrates the relationship: this is a single-port part whose four channels form two pairsets, so the group capability is twice the per-path figure, not four times. That reading carries over to other datasheets — a bare figure with no stated scope should not be multiplied out by a channel count. When budgeting port power, tell us the per-port current you are targeting and VOOHU will confirm. The part is listed in the18G BASE-T range.
