LP2994 DDR Termination Regulator
May 2002
LP2994
DDR Termination Regulator
General Description
The LP2994 regulator is designed to provide a linear solution
to meet the JEDEC SSTL-2 and SSTL-3 specifications (Se-
ries Stub Termination Logic) for active termination of DDR-
SDRAM. The device utilizes an internal operational amplifier
to provide linear regulation of V
TT
without the need for
expensive external components. The output stage prevents
shoot through while delivering 1.5A continuous current and
maintaining excellent load regulation. The LP2994 also in-
corporates an active low shutdown pin to tri-state the output
during Suspend To Ram (STR) states.
Patents Pending
Features
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Source and sink current
Low external component count
Independent analog and power rails
Linear topology
Small package SO-8
Low cost and easy to use
Shutdown pin
Applications
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SSTL-2
SSTL-3
DDR-SDRAM Termination
DDR-II Termination
Typical Application Circuit
20045904
FIGURE 1. SSTL-2 V
TT
Termination
漏 2002 National Semiconductor Corporation
DS200459
www.national.com