Other Parts Discussed in Thread: DLP9000X, DLP9000
Hi.
We are in the layout phase of the DLPC910, and a few issues are not clear. Will Appreciate your abbreviation on the matter below:
1. In section "10.1.3.2.1 LVDS Output Bus Skew", it is written that:
"To minimize instantaneous AC current switching in the DMD, the LVDS output bus trace lengths should differ to
produce a recommended 100-200 ps skew from one bus to another. Table 10-4shows two examples how buses
can be skewed assuming 180-200 ps per 1000 mils. Keep in mind the total skew from one bus to another should
be kept below the maximum skew for the DMD.
In Table 10-4 two examples are given for LVDS OUT. (See attached). in one example there is delta of ~2200mil between Group A-B, and ~1700mil between group B-C, and 1050mil between group C-D... but
on Example 2....Group A-B has no delta and C-D also are same length...which contradict the text highlighted in orange above.
- our questions are:
- does this delta is mandatory between each group to another? If yes, what is the min and max to keep? and why example 2 doesn't include that? the current instructions impose long tracng to keep
those deltas which are very difficult for our case where the DLPC910 is very close to the FLEX connector
- is it only for LVDS OUT? What about LVDS IN groups?
- what are the requirements for LVDS IN Groups? Is there a requirement to keep skew between each group to other? A to B, B to C, C to D?