DM385 datasheet(216/281 Pages) TI

216 / 281 page

DM385, DM388

SPRS821D – MARCH 2013 – REVISED DECEMBER 2013

www.ti.com

8.12.3.3 Step 3: Frequency-Domain Specification Guidelines

The PCB differential lines should be drawn in order to satisfy the Step 1 and Step 2 requirements.

However, although the PCB designer may draw the lines carefully, the lines can have poor electrical

performance due to many reasons.

Vertical connections such as vias and non-uniform line connections can degrade the electrical

performance of the differential lines. The ground design around the lines can also affect the electrical

performance. To ensure that the differential lines are well designed, the frequency-domain behavior must

be compared to the frequency-domain specification.

1. Intralane frequency-domain specification

–

Differential-mode characteristics

–

Sdd12, Sdd11/Sdd22

–

Common-mode characteristics

–

Scc11/Scc22

–

Mode-conversion characteristics

–

Scd11, Scd12, Scd21, Scd22, Sdc11, Sdc12, Sdc21, Sdc22

2. Interlane frequency-domain specification

–

Differential-mode characteristics

–

Sdd11/Sdd22

–

Common-mode characteristics

–

Scc11/Scc22

216

Peripheral Information and Timings

Submit Documentation Feedback

Product Folder Links: DM385 DM388

DM385 Datasheet(PDF) 216 Page - Texas Instruments