Datasheet

Application Report
SCEA017 - April 2001
7–281
GTLP in BTL Applications
Steve Blozis Standard Linear & Logic
ABSTRACT
This application report addresses the issues a designer might face when using a GTLP
device in a BTL/FB+ application when a legacy BTL/FB+ bus implementation is still in use.
Key BTL/FB+ and GTLP device characteristics are compared, and additional GTLP
value-added features are discussed.
To demonstrate that GTLP devices can be used in BTL/FB+ applications, the reference
voltage (V
REF
) and termination voltage (V
TT
) were modified to BTL/FB+ specifications in TI’s
20-slot GTLP EVM and waveforms showing system performance are presented. The
experiment has shown GTLP technology is suitable for BTL/FB+ applications if maximum
output-current ratings are observed.
Contents
Introduction 7–282. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Background 7–283. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FB+ and GTLP Characteristics Comparison 7–285. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-Port/Daughter-Card Side of the Device 7–286. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B-Port/Backplane Side of the Device 7–286. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Device Characteristics 7–288. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Advanced Features of GTLP Devices Not Incorporated in FB+ Devices 7–290. . . . . . . . . . . . . . . . .
GTLP Data-Sheet Changes Required for BTL/FB+ Applications 7–291. . . . . . . . . . . . . . . . . . . . . . . . .
GTLP Waveforms in BTL Backplane 7–291. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Frequently Asked Questions 7–295. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusion 7–295. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Glossary 7–296. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Acknowledgment 7–296. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References 7–297. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Intel and Pentium are trademarks of Intel Corp.
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