RT9173D
Cost-Effective, Peak 3A Sink/Source Bus Termination Regulator
General Description
The RT9173D is a simple, cost-effective and high-speed
linear regulator designed to generate termination voltage
in double data rate (DDR) memory system to comply with
the JEDEC SSTL_2 and SSTL_18 or other specific
interfaces such as HSTL, SCSI-2 and SCSI-3 etc. devices
requirements. The regulator is capable of actively sinking
or sourcing continuous 2A or up to 3A transient peak
current while regulating an output voltage to within 40mV.
The output termination voltage cab be tightly regulated to
track 1/2V
DDQ
by two external voltage divider resistors or
the desired output voltage can be pro-grammed by externally
forcing the REFEN pin voltage.
The RT9173D also incorporates a high-speed differential
amplifier to provide ultra-fast response in line/load transient.
Other features include extremely low initial offset voltage,
excellent load regulation, current limiting in bi-directions
and on-chip thermal shut-down protection.
The RT9173D are available in the SOP-8 (Exposed Pad)
surface mount packages.
Features
Ideal for DDR-I, DDR-II and DDR-III V
TT
Applications
Sink and Source Current
2A Continuous Current
Peak 3A for DDRI and DDRII
Peak 2.5A for DDRIII
Integrated Power MOSFETs
Generates Termination Voltage for SSTL_2,
SSTL _18, HSTL, SCSI-2 and SCSI-3 Interfaces
High Accuracy Output Voltage at Full-Load
Output Adjustment by Two External Resistors
Low External Component Count
Shutdown for Suspend to RAM (STR) Functionality
with High-Impedance Output
Current Limiting Protection
On-Chip Thermal Protection
Available in
SOP-8 (Exposed
Pad) Packages
V
IN
and V
CNTL
No Power Sequence Issue
RoHS Compliant and 100% Lead (Pb)-Free
Applications
Desktop PCs, Notebooks, and Workstations
Graphics Card Memory Termination
Set Top Boxes, Digital TVs, Printers
Embedded Systems
Active Termination Buses
DDR-I, DDR-II and DDR-III Memory Systems
Ordering Information
RT9173D
Package Type
SP : SOP-8 (Exposed Pad-Option 1)
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Note :
Richtek Pb-free and Green products are :
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
100% matte tin (Sn) plating.
Pin Configurations
(TOP VIEW)
VIN
GND
REFEN
VOUT
2
8
7
GND
3
6
9
4
5
NC
NC
VCNTL
NC
SOP-8 (Exposed Pad)
DS9173D-06
December 2007
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
