Datasheet

SCEA017
7–291 GTLP in BTL Applications
GTLP Data-Sheet Changes Required for BTL/FB+ Applications
Analysis of high-drive GTLP TI-SPICE model data of GTLP and BTL signal levels shows little
change in dc specifications, timing requirements, and switching characteristics. This is because
the GTLP device always is operated from 3.3-V V
CC
, even if the B-port output voltage is pulled
to 2.1 V. Overall voltage swing is about 0.6 V larger than normal GTLP voltage swings when
operated at BTL signal levels.
GTLP Waveforms in BTL Backplane
The GTLP evaluation module (EVM) backplane (see Figure 6) was designed and manufactured
to allow factory-trained GTLP Product Marketing Engineers worldwide to have a tool to
showcase the GTLP family of products, and to demonstrate how loading and termination affect
signal integrity. Currently, there are units in China, Germany, Japan, Korea, and the United
States. Demonstrations can be scheduled by contacting your local Texas Instruments Technical
Sales Representative or the GTLP team at [e-mail].
– Used to investigate how length/board spacing/driver position affects signal integrity
– 48 bits broken into 8-bit widths at increments of 2, 4, 8, 12, 16, and 20 slots
– One bit for source-synchronous clock option
– Clock-frequency options of 23, 50, 66, 75, 87, and 100 MHz
– Termination-resistor options of 25, 33, 38, and 50 Ω in 20-slot length (Group 1)
Power-Status Lights
1.5-V V
TT
Regulator 3.3 V – Power Supply – 5 V
Figure 6. GTLP EVM Backplane