Datasheet
SCEA019 - January 2001
7–100 Texas Instruments GTLP Frequently Asked Questions
GTLP device naming considerations are:
• The 16XXX and 32XXX function numbers signify Widebus
TM
(16 to 18 bits) and
Widebus+
TM
(32 to 36 bits) bit widths. Typically, octals are XXX only.
• Function numbers of XX9XX signify single-V
CC
operation and the incorporation of BIAS
V
CC
.
• Medium-drive devices are either three or five digits. High-drive devices have the "9"
removed and are four digits long to conform to the prior BTL/FB+ high-drive
device-naming convention.
• The 2-bit high-drive 1394 is designed uniquely to support the 1394 backplane physical-
layer controller and, therefore, was named GTLP1394. Application information is included
in the data sheet. The GTLP1394 is also very useful in providing 2-bit GTLP clock signals
in backplane applications.
• "H" is added after the GTLP family name if bus hold is featured on the A-port I/O pins.
Typical 1394 and 817 applications do not require bus hold, so bus hold was not included
in these devices. Bus hold is not required on B port I/O pins because the termination
resistors keep the bit high if it is not actively pulled low by the device.
18 I know what a bus transceiver is, but what is a UBT?
A UBT
TM
device performs numerous functions that are done by other logic functions by proper
selection of their OE, LE, and CLK control pins (‘16500 or ‘16501 functions) or their OE, LE,
CLK, and CE control pins (‘16600 or ‘16601 functions). The ‘16601 logic function is shown in
Table 4.
Table 4. ’16601 Logic Functions
UBT, Widebus, and Widebus+ are trademarks of Texas Instruments.