LP2998 Datasheet, PDF (1/18 Pages) Intersil Corporation – DDR-II and DDR-I Termination Regulator

December 12, 2007
LP2998
DDR-II and DDR-I Termination Regulator
General Description
The LP2998 linear regulator is designed to meet JEDEC
SSTL-2 and JEDEC SSTL-18 specifications for termination of
DDR-SDRAM and DDR-II memory. The device contains a
high-speed operational amplifier to provide excellent re-
sponse to load transients. The output stage prevents shoot
through while delivering 1.5A continuous current as required
for DDR-SDRAM termination. The LP2998 also incorporates
a V_SENSE pin to provide superior load regulation and a V_REF
output as a reference for the chipset and DIMMs.
An additional feature found on the LP2998 is an active low
shutdown (SD) pin that provides Suspend To RAM (STR)
functionality. When SD is pulled low the V_TT output will tri-
state providing a high impedance output; while, V_REF remains
active. A power savings advantage can be obtained in this
mode through lower quiescent current.
Features
■ ^{Source and sink current}
■ ^{Low output voltage offset}
■ ^{No external resistors required}
■ ^{Linear topology}
■ ^{Suspend to Ram (STR) functionality}
■ ^{Low external component count}
■ ^{Thermal Shutdown}
■ ^{Available in SO-8, PSOP-8 packages}
Applications
■ ^{DDR-I and DDR-II Termination Voltage}
■ ^{SSTL-18 Termination}
■ ^{SSTL-2 and SSTL-3 Termination}
■ ^{HSTL Termination}
Typical Application Circuit
30026918
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