Datasheet

Driver Cards
7–333 GTLP EVM Board Typical Test and Setup Configuration
2.11 Driver Cards
Separate driver and receiver daughter cards were manufactured for use on the
backplane because, even though the bidirectional SN74GTLPH1655 device
is used, each type of card is hardwired to operate in a certain direction. The
driver card generates a data pattern from the system clock and drives the
GTLP lines on the backplane. The GTLP devices are hardwired for clocked
storage in the A-to-B direction. Data is transmitted on the rising edge of the
system clock. The driver card is a six-layer PCB with two signal layers, a
V
CC
plane, a ground plane, then two signal layers. Stackup is shown in
Table 2–6.
Table 2–6. Driver-Card Stackup
Trace Name Use Layer
Copper
Weight (oz)
Physical
Representation
Dielectric
Height (in.)
Dielectric
Name
Top Data signal 1 0.5
0.004 B stage
Internal signal 2 Data signal 2 1
0.004 Core
V
CC
plane V
CC
plane 3 1
0.004 B stage
Ground plane Ground plane 4 1
0.004 Core
Internal signal 3 Data signal 5 1
0.004 B stage
Bottom
Data signal 6 1