The LP2996-N and LP2996A linear regulators are designed to meet the JEDEC SSTL-2
specifications for termination of DDR-SDRAM. The device also supports DDR2, while LP2996A supports
DDR3 and DDR3L VTT bus termination with VDDQ minimum of 1.35 V. The device
contains a high-speed operational amplifier to provide excellent response to load transients. The
output stage prevents shoot through while delivering 1.5-A continuous current and transient peaks
up to 3 A in the application as required for DDR-SDRAM termination. The LP2996-N and LP2996A also
incorporate a VSENSE pin to provide superior load regulation and a VREF output as a reference for
the chipset and DIMMs.
An additional feature found on the LP2996-N and LP2996A is an active-low shutdown
(SD) pin that provides Suspend To RAM (STR) functionality. When
SD is pulled low the VTT output will tri-state providing a high impedance
output, but VREF remains active. A power savings advantage can be obtained in this mode through
lower quiescent current.
TI recommends the LP2998 and LP2998-Q1 devices for automotive applications and DDR
applications that require operating at temperatures below zero.
WEBENCH® design tools can be used by application designers to
generate, optimize, and simlulate applications using the LP2998 and LP2998-Q1.
