EXAR XRP2997_12

X RP 2 9 9 7
2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
October 2012
Rev. 1.2.0
GENERAL DESCRIPTION
APPLICAT IONS
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.
x DDR I/II/III Memory Termination
x Active Termination Buses
x Audio - Video Equipments
x Video - Graphics Cards
Tightly regulating its output voltage within
±2 0mV, 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 V REF pin vo ltage. It maintains
a fast line and
load transient response and
only requires an output capacit
ance 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 .
FEATURES
x DDR1, DDR2 and DDR3 Support
0.75V TT Generation
±20mV Output Voltage Offset
x 2 Amps Continuous Current Sourcing &
Sinking
1.1V to 5.5V Wide Inp
ut Voltage Range
x Adjustable Output Voltage
Built - in
source/sink
over current,
over temperature
and
under - voltage
lockout
pr otection s insure safe o peration
under
abnormal operating conditions.
x Suspend to RAM(STR), Enable & Soft
Start Functions
x Stable with
22 µF Ceramic Capacitor
The XRP2997 meets JEDEC SSTL - 2, SSTL -18,
HSTL, SCSI -1 and SCSI -3 specifications for
DDR S DRAM memories.
x UVLO, Over Temperature and Over
Current Protections
The XRP2997 is offered in a
RoHS compliant,
³JUHHQ´KDORJHQ
free 8 - pin Exposed Pad SOIC
package.
x Pin/Function Compatible
TYPICAL APPLICATION
x Minimal External Components
with
SP2996B
x RoHS Comp OLDQW³*UHHQ´+DORJHQ
8 - Pin SOIC Packag e
DIAGRAM
Fig. 1: XRP2997 DDRIII V
Exar Corporation
48720 Kato Road, Fremont CA 94538, USA
TT
Application Diagram
www.exar.com
Tel. +1 510 668 - 70 00 ±Fax. +1 510 668 - 70 01
X RP 2 9 9 7
2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
ABSOLUTE MAXIMUM RAT
INGS
OPERATING RATINGS
These are stress ratings only and functional operation o
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.
f
Operating Temperature Range .................
7KHUPDO5HVLVWDQFHLJ
JA ................................
7KHUPDO5HVLVWDQFHLJ
JC ................................
- 40°C to +85 °C
...... 60 °C/W
...... 16 °C/W
VIN , V REF, V CNTL ................................
.......... - 0. 3V to 6.0V
Junction Temperature Range ..................
- 40°C to +1 50 °C
Storage Temperature ............................
- 65°C to + 150°C
Lead Temperature (Soldering, 10 sec)
....................
260 °C
ELECTRICAL SPECIFICA
TIONS
Specifications are for an Operating
Ambient Temperature of T A = 25°C only; limits applying over the full Operating Junction
7HPSHUDWXUHUDQJHDUHGHQRWHGE\D³‡´0LQLPXPDQG0D[LPXPOLPLWVDUH
r statistical
correlation. Typical values represent the most likely parametric norm at T
A = 25°C, and are provided for reference purposes
only. Unless otherwise indicated, V
IN = 1.8V/ 1.5 V, V CNTL = 3.3 V, V REF = 0.5x V IN , COUT = 22 µF (ceramic) , T A = 25 °C.
Para meter
VIN , Input Voltage Range
VCNTL, Input Voltage Range
Min.
Typ.
Max.
1. 1
1.8 /1. 5
5.5
V
Keep V CNTL•9IN during power on and
power off sequences (note 4)
2.375
3.3
5.5
V
Keep V CNTL•9IN during power on and
power off sequences (not
e 4)
V
I OUT = 0mA
- 20
+20
mV
I OUT = 0mA (note 1)
- 20
+20
mV
I OUT = 0.1mA to +2A
- 20
+20
mV
I OUT = 0.1mA to
2
90
µA
VREF < 0.2V, V
1
2.5
mA
I OUT = 0mA
1
µA
VREF = 1.25V
VOUT, Output Voltage
VOS, Output Voltage
VREF
Offset
οVLOR, Load Regulation
I Q, Quiescent Current
I CNTL, Operating Current of V
I REF, Bias Current of V
REF
I IL , Current Limit
CNTL
0
2. 4
RDSCHG , Output Discharge
Resistance
Units
Conditions
- 2A
OUT
= OFF
A
Source: V OUT=0.33xV REF
Sink: V OUT=0.95xV IN (n ote 3 )
Ÿ
VREF=0V, V
160
°C
9”9
CNTL ”9JXDUDQWHHGE\GH
(note 4)
30
°C
Guaranteed by design
3
18
25
OUT=
0.3V
Thermal Protection
TSD , Thermal Shutdown
Temperature
Thermal Shutdown Hysteresis
Shutdown Specifications
0. 6
VTRIGGER , Shutdown Threshold
V
0.2
Output ON
VREF = 0V Æ 1.25V
Output OFF
VREF = 1.25V
Note 1: VOS offset is the voltage measurement defined as V
OUT subtracted from V
REF.
Note 2: Load regulation is measured at constant junction temperature, using pulse testing with a
Note 3: Current limit is measured by
applying a short duration current pulse .
Note 4: In order to safely operate your system, V
CNTL must be > V IN .
© 2012 Exar Corporation
2/ 8
Æ 0V
short ON time.
Rev. 1.2.0
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2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
BLOCK DIAGRAM
Fig. 2: XRP2997 Block Diagram
PIN ASSIGNMENT
Fig. 3: XRP2997 Pin Assignment
PIN DESCRIPTION
Name
Pin Number
1
2
Exposed Pad
VIN
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
XRP2997ID BTR- F
³<<´
Temperature
Range
- ƒ&”7
A”ƒ&
<HDU
±³::´
© 2012 Exar Corporation
Marking
XRP2997I
YYWWF
XXXXXX
Package
Packing
Quantity
Exposed pad
SOIC - 8
2.5 K/Tape & Reel
:RUN:HHN
±³
L´Lead
Free Indicator
- ³;´
3/ 8
Note 1
Note 2
RoHS Compliant
Halogen Free
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Rev. 1.2.0
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2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
TYPICAL PERFORMANCE
CHARACTERISTICS
All data t aken at VIN = 1.8 V/1.5V , V CNTL = 3.3 V, VREF = 0.5x VIN , COUT = 22 µF (ceramic) , T A= 25 °C , unless otherwise specified
- Schematic and BOM from Application Information section of this datasheet.
Fig. 4: Turn on and turn off
Fig. 6: Current
Fig. 5: Output Voltage
vs . Temper ature
Fig. 7: Current limit (sinking) vs
limit ( sourcing ) vs . Temperature
© 2012 Exar Corporation
vs . Temperature
4/ 8
. Temperature
Rev. 1.2.0
X RP 2 9 9 7
2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
Fig. 8: VIN =1.5V, V
REF=0.75V
Fig. 10 : VIN =2.5V, V
Fig. 9: VIN =1.8V, V
© 2012 Exar Corporation
REF=1.2
source response
Fig. 9: V
5V source response
REF=0.9V
sink response
5/ 8
IN =1.8V,
V
REF=0.9V
source response
Fig. 11 : VIN =1.5V, V
REF=0.75V
sink response
Fig. 10 : VIN =2.5V, V
REF=1.25V
sink response
Rev. 1.2.0
X RP 2 9 9 7
2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
Fig. 14: V
IN =1.5V,
V
REF=0.75V
Fig. 11 : VIN =2.5V, V
REF=1.25V
Fig. 13 : V IN =1.8V, V
© 2012 Exar Corporation
Fig. 15: V
source short circuit
source short cir
REF=0.9V
cuit
s ink short circuit
6/ 8
IN =1.8V,
V
REF=0.9V
source
short circuit
Fig. 12 : VIN =1.5V, V
REF=0.75V
sink short circuit
Fig. 14 : V IN =2.5V, V
REF=1.25V
sink
short circuit
Rev. 1.2.0
X RP 2 9 9 7
2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
APPLICATION INFORMAT
ION
recommended for optimum transient response
pe rformance.
I NPUT CAPACITOR CIN
L AYOUT CONSIDERATIONS
Select the input capacitor
CIN for voltage
The XRP299 7 is offered in the 8 - pin exposed rating, RMS current rating and capacitance.
pad SOIC package in order to facilitate power
The voltage rating should be at least 50%
dissipation
(heat
dissipation) .
Power
KLJKHU WKDQ WKH UHJXODWRU¶V
PD[LPXP
LQSXW
dissipation
can
be
maximized
by
soldering
the
voltage. The value o f this capacitor , its charge,
exposed pad to a large
land area on top layer
should be select ed in order to be able to
of
PCB
and
by
using
vias
to connect the
supply enough current to
the XRP2997 in the
exposed
pad
to
an
interlayer
(s) or bottom
event of a transient increase
of source current
layer.
All
capacitors
should
be
placed
as
close
required. A minimum value of 10
µF is advised
as
possible
to
the
respective
pins.
while a recomm ended value of 47 µF is
PACKAGE SPECIFICATIO
N
8 - P IN SOIC EXPOSED P AD
Unit: mm (inch)
Eject hole, oriented hole and mold mark are optional.
© 2012 Exar Corporation
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Rev. 1.2.0
X RP 2 9 9 7
2 A D D R I / I I / I I I B u s Te r m i n a t i o n Re g u l a t o r
REVISION HISTORY
Revision
Date
Description
1.0.0
07 / 22 /2011
Initial release of datasheet
1.1.0
01/09/201 2
Corrected part number in ordering information
1.1.1
03/29/2012
Corrected turn on threshold from 0.8V to 0.6V. Typographical error.
1.2.0
10/29/2012
Reformat of datasheet
Updated typical application
schematics (figure 1)
Addition of CIN selection under
Application Informat
FOR FURTHER ASSISTAN
Email:
ion section
CE
[email protected]
[email protected]
Exar Technical Documentation:
http://www.exar.com/TechDoc/default.aspx?
EXAR CORPORATION
H EADQUARTERS AND
SALES O FFICES
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 Corpor
ation 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. Char ts and schedules contained here
in are only for illustration purposes and may vary depending upon a
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,
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, in
writi ng, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all
such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances.
Reproduction, in part or whole,
© 2012 Exar Corporation
or
its
without the prior written consent of EXAR Corporation is prohibited.
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Rev. 1.2.0