Datasheet

SCEA017
7–290 GTLP in BTL Applications
• ESD – Both FB+ and GTLP meet the minimum electrostatic discharge (ESD) standards in
human-body model (HBM), 2000 V; machine model (MM), 200 V; and charged-device model
(CDM), 1000 V. During testing, the GTLP devices pass 4000-V HBM and 3000-V CDM.
• Temperature ranges – FB+ is offered in commercial (0°C to 70°C) and military (–55°C to
125°C) temperature ranges, with some of the newer devices also ac specified for the
industrial (–40°C to 85°C) temperature range. GTLP is offered in industrial (–40°C to 85°C)
and select devices will be offered in the military (–55°C to 125°C) temperature ranges.
Please contact the GTLP team at [e-mail] for additional information on the devices in
the military temperature range.
• Package offerings – FB+ devices are packaged in older technology, larger, more expensive
thin quad flatpack packages that include a thermal heat sink in the 100-pin packages to help
dissipate the heat generated by the bipolar outputs. GTLP devices are packaged in modern
packages, including the often-requested TSSOP package and, where possible, in the
smaller TVSOP packages. Select GTLP devices also are offered in the new very fine-pitch
ball grid array (VFBGA) and the dual-die, low-profile, fine-pitch ball grid array (LFBGA)
package.
• IEEE Std 1149.1 JTAG – Most FB+ devices have JTAG TAP pins assigned, but no devices
with JTAG features have been released. The GTLP team is evaluating JTAG functionality in
GTLP devices in VFBGA/LFBGA packages, and solicits your input on the desirability of this
feature.
• Price – Comparing suggested resale pricing, the FB2033 is about 85% higher than the
GTLP2033. There are similar price differentials for other devices in both families.
Advanced Features of GTLP Devices Not Incorporated in FB+ Devices
• OEC circuitry – The low-to-high transition output edge-control circuitry has been improved
significantly. The slew rate has been held to about 0.5 V/ns on the rising edge and helps
prevent ringing on heavily loaded backplanes, allowing a much higher maximum frequency.
• TI-OPC circuitry – GTLP devices feature overshoot-protection circuitry that actively ports
backplane energy to GND when the signal level is greater than 0.7 V to 0.8 V above V
REF
.
This prevents large overshoots on improperly terminated or unevenly loaded backplanes
during low-to-high signal transition, which limits the subsequent undershoot that would
reduce the upper noise margin.
• Edge-rate control (ERC) – This feature allows designers to select either a slow-rising-edge
slew rate (about 0.4 V/ns) or a slightly faster slew rate (about 0.45 V/ns). The faster slew
rate reduces the maximum propagation delay, allowing a higher system frequency. The
maximum frequency with a slow ERC is about 87 MHz, while a fast ERC is about 125 MHz.
In BTL applications, the slow ERC should be selected by applying the correct logic level to
the external ERC control pin as shown in Table 4. ERC
is the inverse of ERC and is
implemented on some GTLP devices where the control pin replaced a GND pin in the
comparable medium-drive GTLP device.
Table 4. B-Port Edge-Rate Control
LOGIC LEVEL
B-PORT
ERC ERC
OUTPUT EDGE RATE
H L Slow
L H Fast