CM3131
Triple Linear Voltage Regulator for DDR-I/-II Memory
Features
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Integrated power solution for DDR-I and DDR-II
memory systems with few external components
Three all-linear regulators for V
DDQ
, V
TT
and
V
STBY
power supply applications
Lowest system cost and smallest footprint for
DDR power solutions
V
DDQ
regulator/driver utilizes external N-FET to
provide up to 15A current at 2.5V/1.8V
V
TT
source/sink regulator provides up to 2A at
1.25V for DDR-I systems or 0.65A at 0.9V for
the DDR-II memory controller (not DDR-II
memory)
LDO standby regulator provides up to 500mA at
2.5V for DDR-I and at 1.8V for DDR-II systems
Can be ganged for higher current applications
Over temperature and reverse current protection
Over current protection for V
STBY
and V
TT
regulator
Available in 8 lead and 14 lead PSOP packages
Lead-free versions available
Product Description
The CM3131 family of all-linear regulators provides
an integrated power solution for DDR-I/-II memory
systems in both run-time and standby modes of
operation. The CM3131 is ideal for designs
incorporating both a main 3.3V and a standby (3.3V
or 5V) supply. The CM3131 features three
independent linear regulators for V
DDQ
, V
TT
and V
STBY
supply regulation and will maintain an accuracy of
±1% across the operating temperature range.
The CM3131 is offered in two configurations. The
CM3131-01/11 drives a single external N-FET on a
single V
DDQ
rail. The CM3131-02 drives two external
unmatched N-FETs on two V
DDQ
rails. Each V
DDQ
rail
incorporates an adjustment pin (SENSE) to enable
setting V
DDQ
in the 2.2V to 2.8V range, supporting
DIMMs with different supply requirements or DDR-II
type devices.
The CM3131-01/11 is available in 8-lead PSOP
package and the CM3131-02 is available in 14-lead
PSOP package.
The CM3131 devices are also available with optional
lead-free finishing.
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Applications
Desktop PCs, notebooks, and workstations
Set top boxes, digital TVs, printers
Embedded systems
Electrical Schematic
© 2004 California Micro Devices Corp. All rights reserved.
02/02/04
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
Tel: 408.263.3214
Fax: 408.263.7846
www.calmicro.com
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CALMIRCO [ CALIFORNIA MICRO DEVICES CORP ]
