EXAR XRP2997IDB-F

X RP 2 9 9 7
2A DDR I/II/III Bus Termination Regulator
July 2011
Rev. 1.0.0
GENERAL DESCRIPTION
APPLICATIONS
The XRP2997 is a Double Data Rate (DDR)
termination voltage regulator supporting all
power requirements of DDR I, II and III
memories and is capable of sinking or sourcing
2A continuously.
Tightly regulating its output voltage within
±20mV, the XRP2997 converts input voltages
as low as 1.1V while the output voltage is
adjustable through an external resistor divider
or by forcing the VREF pin voltage. It maintains
a fast line and load transient response and
only requires an output capacitance of 22µF to
operate. An enable function via an external
MOSFET and a soft start feature allow for a
controlled
implementation
of
power-up
sequencing.
Built-in
source/sink
overcurrent,
overtemperature
and
under-voltage
lockout
protections insure safe operation under
abnormal operating conditions.
 DDR I/II/III Memory Termination
 Active Termination Buses
 Audio-Video Equipments
 Video-Graphics Cards
FEATURES
 DDR1, DDR2 and DDR3 Support
 0.75VTT Generation
 ±20mV Output Voltage Offset
 2 Amps Continuous Current Sourcing &
Sinking
 1.1V to 5.5V Wide Input Voltage Range
 Adjustable Output Voltage
 Suspend to RAM(STR), Enable & Soft
Start Functions
 Stable with 22µF Ceramic Capacitor
The XRP2997 meets JEDEC SSTL-2, SSTL-18,
HSTL, SCSI-1 and SCSI-3 specifications for
DDR SDRAM memories.
 UVLO, Over Temperature and Over
Current Protections
The XRP2997 is offered in a RoHS compliant,
“green”/halogen free 8-pin Exposed Pad SOIC
package.
 Pin/Function Compatible with SP2996B
 Minimal External Components
 RoHS Compliant “Green”/Halogen Free
8-Pin SOIC Package
TYPICAL APPLICATION DIAGRAM
Fig. 1: XRP2997 DDRIII VTT Application Diagram
Exar Corporation
48720 Kato Road, Fremont CA 94538, USA
www.exar.com
Tel. +1 510 668-7000 – Fax. +1 510 668-7001
X RP 2 9 9 7
2A DDR I/II/III Bus Termination Regulator
ABSOLUTE MAXIMUM RATINGS
OPERATING RATINGS
These are stress ratings only and functional operation of
the device at these ratings or any other above those
indicated in the operation sections of the specifications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect
reliability.
Operating Temperature Range ................. -40°C to +85°C
Thermal Resistance θJA ...................................... 60°C/W
Thermal Resistance θJC ...................................... 16°C/W
VIN, VREF, VCNTL .......................................... -0.3V to 6.0V
Junction Temperature Range.................. -40°C to +150°C
Storage Temperature ............................ -65°C to +150°C
Lead Temperature (Soldering, 10 sec) ................... 260°C
ELECTRICAL SPECIFICATIONS
Specifications are for an Operating Ambient Temperature of TA = 25°C only; limits applying over the full Operating Junction
Temperature range are denoted by a “•”. Minimum and Maximum limits are guaranteed through test, design, or statistical
correlation. Typical values represent the most likely parametric norm at TA = 25°C, and are provided for reference purposes
only. Unless otherwise indicated, VIN = 1.8V/1.5V, VCNTL = 3.3V, VREF = 0.5xVIN, COUT = 22µF (ceramic), TA= 25°C.
Parameter
VIN, Input Voltage Range
VCNTL, Input Voltage Range
Min.
∆VLOR, Load Regulation
Max.
Units
Conditions
1.1
1.8/1.5
5.5
V
Keep VCNTL≥VIN during power on and
power off sequences (note 4)
2.375
3.3
5.5
V
Keep VCNTL≥VIN during power on and
power off sequences (note 4)
V
IOUT = 0mA
-20
+20
mV
-20
+20
mV
IOUT = 0.1mA to +2A
-20
+20
mV
IOUT = 0.1mA to -2A
VOUT, Output Voltage
VOS, Output Voltage Offset
Typ.
VREF
IOUT = 0mA (note 1)
IQ, Quiescent Current
2
90
µA
VREF < 0.2V, VOUT = OFF
ICNTL, Operating Current of VCNTL
1
2.5
mA
IOUT = 0mA
1
µA
IREF, Bias Current of VREF
IIL, Current Limit
0
2.4
RDSCHG, Output Discharge
Resistance
VREF = 1.25V
A
Source: VOUT=0.33xVREF
Sink: VOUT=0.95xVIN (note 3)
Ω
VREF=0V, VOUT=0.3V
160
°C
3.3V ≤ VCNTL ≤ 5V, guaranteed by design
(note 4)
30
°C
Guaranteed by design
3
18
25
Thermal Protection
TSD, Thermal Shutdown
Temperature
Thermal Shutdown Hysteresis
Shutdown Specifications
0.8
VTRIGGER, Shutdown Threshold
V
0.2
Note
Note
Note
Note
1:
2:
3:
4:
Output ON
VREF = 0V  1.25V
Output OFF
VREF = 1.25V  0V
VOS offset is the voltage measurement defined as VOUT subtracted from VREF.
Load regulation is measured at constant junction temperature, using pulse testing with a short ON time.
Current limit is measured by applying a short duration current pulse.
In order to safely operate your system, VCNTL must be > VIN.
© 2011 Exar Corporation
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X RP 2 9 9 7
2A DDR I/II/III Bus Termination Regulator
BLOCK DIAGRAM
Fig. 2: XRP2997 Block Diagram
PIN ASSIGNMENT
Fig. 3: XRP2997 Pin Assignment
PIN DESCRIPTION
Name
Pin Number
VIN
1
2
Exposed Pad
GND
Description
Power Input Voltage
Ground Signal
3
Reference Input Voltage.
This input can also be used as an enable signal; pulling this pin low shuts down the
XRP2997. Refer to typical application circuit.
VOUT
4
Output Voltage
NC
5, 7, 8
VCNTL
6
VREF
NC
Voltage for the driver circuit and all analog blocks
ORDERING INFORMATION
Part Number
Temperature
Range
Marking
XRP2997IDB-F/TR
-40°C≤TA≤+85°C
XRP2997I
YYWWF
XXXXXX
Package
Packing
Quantity
Note 1
Note 2
Exposed pad
2.5K/Tape & Reel RoHS Compliant
SOIC-8
Halogen Free
“YY” = Year – “WW” = Work Week – “L” = Lead Free Indicator - “X” = Lot Number; when applicable.
© 2011 Exar Corporation
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2A DDR I/II/III Bus Termination Regulator
TYPICAL PERFORMANCE CHARACTERISTICS
All data taken at VIN = 1.8V/1.5V, VCNTL = 3.3V, VREF = 0.5xVIN, COUT = 22µF (ceramic), TA= 25°C, unless otherwise specified
- Schematic and BOM from Application Information section of this datasheet.
Fig. 4: Turn on and turn off vs. Temperature
Fig. 5: Output Voltage vs. Temperature
Fig. 6: Current limit (sourcing) vs. Temperature
Fig. 7: Current limit (sinking) vs. Temperature
Fig. 8: VIN=1.5V, VREF=0.75V source response
Fig. 9: VIN=1.8V, VREF=0.9V source response
© 2011 Exar Corporation
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2A DDR I/II/III Bus Termination Regulator
Fig. 10: VIN=2.5V, VREF=1.25V source response
Fig. 11: VIN=1.5V, VREF=0.75V sink response
Fig. 9: VIN=1.8V, VREF=0.9V sink response
Fig. 10: VIN=2.5V, VREF=1.25V sink response
Fig. 14: VIN=1.5V, VREF=0.75V source short circuit
Fig. 15: VIN=1.8V, VREF=0.9V source short circuit
© 2011 Exar Corporation
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2A DDR I/II/III Bus Termination Regulator
Fig. 11: VIN=2.5V, VREF=1.25V source short circuit
Fig. 12: VIN=1.5V, VREF=0.75V sink short circuit
Fig. 13: VIN=1.8V, VREF=0.9V sink short circuit
Fig. 14: VIN=2.5V, VREF=1.25V sink short circuit
exposed pad to a large land area on top layer
of PCB and by using vias to connect the
exposed pad to an interlayer(s) or bottom
layer. All capacitors should be placed as close
as possible to the respective pins.
APPLICATION INFORMATION
LAYOUT CONSIDERATIONS
The XRP2997 is offered in the 8-pin exposedpad SOIC package in order to facilitate power
dissipation
(heat
dissipation).
Power
dissipation can be maximized by soldering the
© 2011 Exar Corporation
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2A DDR I/II/III Bus Termination Regulator
PACKAGE SPECIFICATION
8-PIN SOIC EXPOSED PAD
Unit: mm (inch)
Eject hole, oriented hole and mold mark are optional.
© 2011 Exar Corporation
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Rev. 1.0.0
X RP 2 9 9 7
2A DDR I/II/III Bus Termination Regulator
REVISION HISTORY
Revision
Date
1.0.0
07/22/2011
Description
Initial release of datasheet
FOR FURTHER ASSISTANCE
Email:
[email protected]
Exar Technical Documentation:
http://www.exar.com/TechDoc/default.aspx?
EXAR CORPORATION
HEADQUARTERS AND SALES OFFICES
48720 Kato Road
Fremont, CA 94538 – USA
Tel.: +1 (510) 668-7000
Fax: +1 (510) 668-7030
www.exar.com
NOTICE
EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve
design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein,
conveys no license under any patent or other right, and makes no representation that the circuits are free of patent
infringement. Charts and schedules contained herein are only for illustration purposes and may vary depending upon a
user’s specific application. While the information in this publication has been carefully checked; no responsibility, however,
is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the failure
malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect
safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives,
writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes
such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances.
or
its
in
all
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
© 2011 Exar Corporation
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