LP2997MRX/NOPB [TI]

DDR-II 终止稳压器 | DDA | 8 | 0 to 125;
LP2997MRX/NOPB
型号: LP2997MRX/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
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DDR-II 终止稳压器 | DDA | 8 | 0 to 125

双倍数据速率 光电二极管 接口集成电路 稳压器
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LP2997  
www.ti.com  
SNVS295F MAY 2004REVISED APRIL 2013  
LP2997 DDR-II Termination Regulator  
Check for Samples: LP2997  
1
FEATURES  
DESCRIPTION  
The LP2997 linear regulator is designed to meet the  
JEDEC SSTL-18 specifications for termination of  
DDR-II memory. The device contains a high-speed  
operational amplifier to provide excellent response to  
load transients. The output stage prevents shoot  
through while delivering 500mA continuous current  
and transient peaks up to 900mA in the application as  
required for DDR-II SDRAM termination. The LP2997  
also incorporates a VSENSE pin to provide superior  
load regulation and a VREF output as a reference for  
the chipset and DIMMs.  
2
Source and Sink Current  
Low Output Voltage Offset  
No External Resistors Required  
Linear Topology  
Suspend to Ram (STR) Functionality  
Low External Component Count  
Thermal Shutdown  
Available in SOIC-8, SO PowerPAD-8 Packages  
An additional feature found on the LP2997 is an  
active low shutdown (SD) pin that provides Suspend  
To RAM (STR) functionality. When SD is pulled low  
APPLICATIONS  
DDR-II Termination Voltage  
SSTL-18 Termination  
the VTT output will tri-state providing  
a
high  
impedance output, but, VREF will remain active. A  
power savings advantage can be obtained in this  
mode through lower quiescent current.  
Typical Application Circuit  
LP2997  
0.9V  
=
VREF  
VREF  
SD  
AV  
SD  
+
+
CREF  
AVIN = 2.5V  
IN  
V SENSE  
VTT  
VDDQ  
PV  
VDDQ = 1.8V  
V TT= 0.9V  
IN  
+
GND  
CIN  
C OUT  
Figure 1. Typical Application Circuit  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
All trademarks are the property of their respective owners.  
2
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2004–2013, Texas Instruments Incorporated  
LP2997  
SNVS295F MAY 2004REVISED APRIL 2013  
www.ti.com  
Connection Diagram  
1
1
2
3
4
8
7
6
5
8
7
6
5
VTT  
VTT  
GND  
GND  
SD  
2
PVIN  
AVIN  
VDDQ  
PVIN  
AVIN  
VDDQ  
SD  
GND  
3
VSENSE  
VSENSE  
VREF  
4
VREF  
Figure 2. SO PowerPAD-8 Layout  
See Package Number DDA (R-PDSO-G8)  
Figure 3. SOIC-8 Layout  
See Package Number D0008A  
PIN DESCRIPTIONS  
SOIC-8 Pin or  
SO PowerPAD-8 Pin  
Name  
Function  
1
2
3
4
5
6
7
8
GND  
SD  
Ground  
Shutdown  
VSENSE  
VREF  
VDDQ  
AVIN  
PVIN  
VTT  
Feedback pin for regulating VTT.  
Buffered internal reference voltage of VDDQ/2  
Input for internal reference equal to VDDQ/2  
Analog input pin  
Power input pin  
Output voltage for connection to termination resistors  
Exposed pad thermal connection Connect to Ground  
EP  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
Absolute Maximum Ratings(1)(2)  
AVIN to GND  
0.3V to +6V  
-0.3V to AVIN  
0.3V to +6V  
65°C to +150°C  
150°C  
PVIN to GND  
VDDQ(3)  
Storage Temp. Range  
Junction Temperature  
Lead Temperature (Soldering, 10 sec)  
260°C  
SOIC-8 Thermal Resistance (θJA  
)
151°C/W  
SO PowerPAD-8 Thermal Resistance (θJA  
)
43°C/W  
Minimum ESD Rating(4)  
1kV  
(1) Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating range indicates conditions for which  
the device is intended to be functional, but does not ensure specific performance limits. For specific specifications and test conditions  
see Electrical Characteristics. The specified specifications apply only for the test conditions listed. Some performance characteristics  
may degrade when the device is not operated under the listed test conditions.  
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and  
specifications.  
(3) VDDQ voltage must be less than 2 x (AVIN - 1) or 6V, whichever is smaller.  
(4) The human body model is a 100pF capacitor discharged through a 1.5kresistor into each pin.  
Operating Range  
Junction Temp. Range(1)  
0°C to +125°C  
2.2V to 5.5V  
AVIN to GND  
(1) At elevated temperatures, devices must be derated based on thermal resistance. The device in the SOIC-8 package must be derated at  
θJA = 151.2° C/W junction to ambient with no heat sink.  
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SNVS295F MAY 2004REVISED APRIL 2013  
Electrical Characteristics  
Specifications with standard typeface are for TJ = 25°C and limits in boldface type apply over the full Operating  
Temperature Range (TJ = 0°C to +125°C)(1). Unless otherwise specified, AVIN = 2.5V, PVIN = 1.8V, VDDQ = 1.8V.  
Symbol  
Parameter  
VREF Voltage  
Conditions  
Min  
Typ  
Max  
Units  
V
VREF  
PVIN = VDDQ = 1.7V  
PVIN = VDDQ = 1.8V  
PVIN = VDDQ = 1.9V  
0.837  
0.887  
0.936  
0.860  
0.910  
0.959  
0.887  
0.937  
0.986  
ZVREF  
VTT  
VREF Output Impedance  
VTT Output Voltage  
IREF = -30 to +30 μA  
2.5  
kΩ  
IOUT = 0A  
PVIN = VDDQ = 1.7V  
PVIN = VDDQ = 1.8V  
PVIN = VDDQ = 1.9V  
IOUT = ±0.5A(2)  
0.822  
0.874  
0.923  
0.856  
0.908  
0.957  
0.887  
0.939  
0.988  
V
PVIN = VDDQ = 1.7V  
PVIN = VDDQ = 1.8V  
PVIN = VDDQ = 1.9V  
0.828  
0.878  
0.928  
0.856  
0.908  
0.957  
0.890  
0.940  
0.990  
VosTT/VTT  
VTT Output Voltage Offset  
IOUT = 0A  
IOUT = -0.5A  
IOUT = +0.5A  
-25  
-25  
-25  
0
0
0
25  
25  
25  
(VREF-VTT  
)
mV  
IQ  
Quiescent Current(3)  
IOUT = 0A(3)  
320  
100  
115  
500  
µA  
kΩ  
µA  
ZVDDQ  
ISD  
VDDQ Input Impedance  
Quiescent Current in  
Shutdown(3)  
SD = 0V  
150  
5
IQ_SD  
VIH  
Shutdown Leakage Current SD = 0V  
2
µA  
V
Minimum Shutdown High  
Level  
1.9  
VIL  
Maximum Shutdown Low  
Level  
0.8  
V
ISENSE  
TSD  
VSENSE Input Current  
13  
165  
10  
nA  
Thermal Shutdown  
See(4)  
Celsius  
Celsius  
TSD_HYS  
Thermal Shutdown  
Hysteresis  
(1) Limits are 100% production tested at 25°C. Limits over the operating temperature range are specified through correlation using  
Statistical Quality Control (SQC) methods. The limits are used to calculate Average Outgoing Quality Level (AOQL).  
(2) VTT load regulation is tested by using a 10 ms current pulse and measuring VTT  
.
(3) Quiescent current defined as the current flow into AVIN.  
(4) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction to ambient thermal  
resistance, θJA, and the ambient temperature, TA. Exceeding the maximum allowable power dissipation will cause excessive die  
temperature and the regulator will go into thermal shutdown.  
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Typical Performance Characteristics  
Iq vs AVIN in SD  
Iq vs AVIN  
400  
350  
300  
250  
200  
150  
100  
50  
1050  
900  
750  
600  
450  
300  
150  
0
2
2
0
2.5  
3
3.5  
4
4.5  
5
5.5  
2
0
2
2.5  
3
3.5  
4
4.5  
5
5.5  
AVIN (V)  
AVIN (V)  
Figure 4.  
Figure 5.  
VIH and VIL  
VREF vs VDDQ  
4
3.5  
3
3
2.5  
2
2.5  
2
1.5  
1
1.5  
1
0.5  
0
0.5  
2.5  
3
3.5  
4
4.5  
5
5.5  
1
2
3
4
5
6
AVIN (V)  
VDDQ (V)  
Figure 6.  
Figure 7.  
VTT vs VDDQ  
Iq vs AVIN in SD Temperature  
3
2.5  
2
400  
350  
300  
250  
200  
150  
100  
50  
0oC  
125oC  
1.5  
1
0.5  
0
1
2
3
4
5
6
2.5  
3
3.5  
4
4.5  
5
5.5  
VDDQ (V)  
AVIN (V)  
Figure 8.  
Figure 9.  
4
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Typical Performance Characteristics (continued)  
Maximum Sourcing Current vs AVIN  
(VDDQ = 1.8V, PVIN = 1.8V)  
Iq vs AVIN Temperature  
1050  
900  
750  
600  
450  
300  
150  
0
1.4  
1.2  
1
85oC  
25oC  
0.8  
0.6  
0.4  
0.2  
0
0oC  
2
2.5  
3
3.5  
4
4.5  
5
5.5  
2
2.5  
3
3.5  
4
4.5  
5
5.5  
AVIN (V)  
AVIN (V)  
Figure 10.  
Figure 11.  
Maximum Sinking Current vs AVIN  
(VDDQ = 1.8V)  
2.4  
2.2  
2
1.8  
1.6  
1.4  
1.2  
1
2
2.5  
3
3.5  
4
4.5  
5
5.5  
AVIN (V)  
Figure 12.  
Block Diagram  
VDDQ  
AVIN  
PVIN  
SD  
50k  
50k  
-
+
-
VREF  
VTT  
+
VSENSE  
GND  
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LP2997  
SNVS295F MAY 2004REVISED APRIL 2013  
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DESCRIPTION  
The LP2997 is a linear bus termination regulator designed to meet the JEDEC requirements of SSTL-18. The  
output, VTT is capable of sinking and sourcing current while regulating the output voltage equal to VDDQ / 2. The  
output stage has been designed to maintain excellent load regulation while preventing shoot through. The  
LP2997 also incorporates two distinct power rails that separates the analog circuitry from the power output stage.  
This allows a split rail approach to be utilized to decrease internal power dissipation. It also permits the LP2997  
to provide a termination solution for the next generation of DDR-SDRAM memory (DDRII).  
Pin Descriptions  
AVIN AND PVIN AVIN and PVIN are the input supply pins for the LP2997. AVIN is used to supply all the internal control circuitry. PVIN,  
however, is used exclusively to provide the rail voltage for the output stage used to create VTT. These pins have the capability to work off  
separate supplies, under the condition that AVIN is always greater than or equal to PVIN. For SSTL-18 applications, it is recommended to  
connect PVIN to the 1.8V rail used for the memory core and AVIN to a rail within its operating range of 2.2V to 5.5V (typically a 2.5V  
supply). PVIN should always be used with either a 1.8V or 2.5V rail. This prevents the thermal limit from tripping because of excessive  
internal power dissipation. If the junction temperature exceeds the thermal shutdown than the part will enter a shutdown state identical to  
the manual shutdown where VTT is tri-stated and VREF remains active. A lower rail such as 1.5V can be used but it will reduce the maximum  
output current, therefore it is not recommended for most termination schemes.  
VDDQ VDDQ is the input used to create the internal reference voltage for regulating VTT. The reference voltage is generated from a resistor  
divider of two internal 50kresistors. This ensures that VTT will track VDDQ / 2 precisely. The optimal implementation of VDDQ is as a  
remote sense. This can be achieved by connecting VDDQ directly to the 1.8V rail at the DIMM instead of PVIN. This ensures that the  
reference voltage tracks the DDR memory rails precisely without a large voltage drop from the power lines. For SSTL-18 applications  
VDDQ will be a 1.8V signal, which will create a 0.9V termination voltage at VTT (See Electrical Characteristics Table for exact values of VTT  
over temperature).  
VSENSE The purpose of the sense pin is to provide improved remote load regulation. In most motherboard applications the termination  
resistors will connect to VTT in a long plane. If the output voltage was regulated only at the output of the LP2997 then the long trace will  
cause a significant IR drop resulting in a termination voltage lower at one end of the bus than the other. The VSENSE pin can be used to  
improve this performance, by connecting it to the middle of the bus. This will provide a better distribution across the entire termination bus.  
If remote load regulation is not used then the VSENSE pin must still be connected to VTT. Care should be taken when a long VSENSE trace is  
implemented in close proximity to the memory. Noise pickup in the VSENSE trace can cause problems with precise regulation of VTT. A small  
0.1uF ceramic capacitor placed next to the VSENSE pin can help filter any high frequency signals and preventing errors.  
SHUTDOWN The LP2997 contains an active low shutdown pin that can be used for suspend to RAM functionality. In this condition the VTT  
output will tri-state while the VREF output remains active providing a constant reference signal for the memory and chipset. During shutdown  
VTT should not be exposed to voltages that exceed PVIN. With the shutdown pin asserted low the quiescent current of the LP2997 will drop,  
however, VDDQ will always maintain its constant impedance of 100kfor generating the internal reference. Therefore, to calculate the total  
power loss in shutdown both currents need to be considered. For more information refer to the Thermal Dissipation section. The shutdown  
pin also has an internal pull-up current; therefore, to turn the part on the shutdown pin can either be connected to AVIN or left open  
VREF VREF provides the buffered output of the internal reference voltage VDDQ / 2. This output should be used to provide the reference  
voltage for the Northbridge chipset and memory. Since these inputs are typically an extremely high impedance, there should be little current  
drawn from VREF. For improved performance, an output bypass capacitor can be used, located close to the pin, to help with noise. A  
ceramic capacitor in the range of 0.1 µF to 0.01 µF is recommended. This output remains active during the shutdown state and thermal  
shutdown events for the suspend to RAM functionality.  
VTT VTT is the regulated output that is used to terminate the bus resistors. It is capable of sinking and sourcing current while regulating the  
output precisely to VDDQ / 2. The LP2997 is designed to handle continuous currents of up to +/- 0.5A with excellent load regulation. If a  
transient is expected to last above the maximum continuous current rating for a significant amount of time, then the bulk output capacitor  
should be sized large enough to prevent an excessive voltage drop. If the LP2997 is to operate in elevated temperatures for long durations  
care should be taken to ensure that the maximum junction temperature is not exceeded. Proper thermal de-rating should always be used.  
(Please refer to the Thermal Dissipation section) If the junction temperature exceeds the thermal shutdown point than VTT will tri-state until  
the part returns below the temperature hysteresis trip-point  
COMPONENT SELECTIONS  
INPUT CAPACITOR  
The LP2997 does not require a capacitor for input stability, but it is recommended for improved performance  
during large load transients to prevent the input rail from dropping. The input capacitor should be located as  
close as possible to the PVIN pin. Several recommendations exist dependent on the application required. A  
typical value recommended for AL electrolytic capacitors is 22 µF. Ceramic capacitors can also be used. A value  
in the range of 10 µF with X5R or better would be an ideal choice. The input capacitance can be reduced if the  
LP2997 is placed close to the bulk capacitance from the output of the 1.8V DC-DC converter. For the AVIN pin, a  
small 0.1uF ceramic capacitor is sufficient to prevent excessive noise from coupling into the device.  
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OUTPUT CAPACITOR  
The LP2997 has been designed to be insensitive of output capacitor size or ESR (Equivalent Series Resistance).  
This allows the flexibility to use any capacitor desired. The choice for output capacitor will be determined solely  
on the application and the requirements for load transient response of VTT. As a general recommendation the  
output capacitor should be sized above 100 µF with a low ESR for SSTL applications with DDR-SDRAM. The  
value of ESR should be determined by the maximum current spikes expected and the extent at which the output  
voltage is allowed to droop. Several capacitor options are available on the market and a few of these are  
highlighted below:  
AL - It should be noted that many aluminum electrolytics only specify impedance at a frequency of 120 Hz, which  
indicates they have poor high frequency performance. Only aluminum electrolytics that have an impedance  
specified at a higher frequency (100 kHz) should be used for the LP2997. To improve the ESR several AL  
electrolytics can be combined in parallel for an overall reduction. An important note to be aware of is the extent  
at which the ESR will change over temperature. Aluminum electrolytic capacitors can have their ESR rapidly  
increase at cold temperatures.  
Ceramic - Ceramic capacitors typically have a low capacitance, in the range of 10 to 100 µF range, but they have  
excellent AC performance for bypassing noise because of very low ESR (typically less than 10 m). However,  
some dielectric types do not have good capacitance characteristics as a function of voltage and temperature.  
Because of the typically low value of capacitance it is recommended to use ceramic capacitors in parallel with  
another capacitor such as an aluminum electrolytic. A dielectric of X5R or better is recommended for all ceramic  
capacitors.  
Hybrid - Several hybrid capacitors such as OS-CON and SP are available from several manufacturers. These  
offer a large capacitance while maintaining a low ESR. These are the best solution when size and performance  
are critical, although their cost is typically higher than any other capacitors.  
Thermal Dissipation  
Since the LP2997 is a linear regulator any current flow from VTT will result in internal power dissipation  
generating heat. To prevent damaging the part from exceeding the maximum allowable junction temperature,  
care should be taken to derate the part dependent on the maximum expected ambient temperature and power  
dissipation. The maximum allowable internal temperature rise (TRmax) can be calculated given the maximum  
ambient temperature (TAmax) of the application and the maximum allowable junction temperature (TJmax).  
TRmax = TJmax TAmax  
(1)  
From this equation, the maximum power dissipation (PDmax) of the part can be calculated:  
PDmax = TRmax / θJA  
(2)  
The θJA of the LP2997 will be dependent on several variables: the package used; the thickness of copper; the  
number of vias and the airflow. For instance, the θJA of the SOIC-8 is 163°C/W with the package mounted to a  
standard 8x4 2-layer board with 1oz. copper, no airflow, and 0.5W dissipation at room temperature. This value  
can be reduced to 151.2°C/W by changing to a 3x4 board with 2 oz. copper that is the JEDEC standard.  
Figure 13 shows how the θJA varies with airflow for the two boards mentioned.  
180  
170  
160  
150  
140  
130  
120  
110  
100  
90  
SOP Board  
JEDEC Board  
80  
0
200  
400  
600  
800  
1000  
AIRFLOW (Linear Feet per Minute)  
Figure 13. θJA vs Airflow (SOIC-8)  
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Additional improvements can be made by the judicious use of vias to connect the part and dissipate heat to an  
internal ground plane. Using larger traces and more copper on the top side of the board can also help. With  
careful layout it is possible to reduce the θJA further than the nominal values shown in Figure 13.  
Optimizing the θJA and placing the LP2997 in a section of a board exposed to lower ambient temperature allows  
the part to operate with higher power dissipation. The internal power dissipation can be calculated by summing  
the three main sources of loss: output current at VTT, either sinking or sourcing, and quiescent current at AVIN  
and VDDQ. During the active state (when shutdown is not held low) the total internal power dissipation can be  
calculated from the following equations:  
PD = PAVIN + PVDDQ + PVTT  
(3)  
Where,  
PAVIN = IAVIN * VAVIN  
PVDDQ = VVDDQ * IVDDQ = VVDDQ x RVDDQ  
(4)  
(5)  
2
To calculate the maximum power dissipation at VTT both conditions at VTT need to be examined, sinking and  
sourcing current. Although only one equation will add into the total, VTT cannot source and sink current  
simultaneously.  
PVTT = VVTT x ILOAD (Sinking) or  
(6)  
(7)  
PVTT = ( VPVIN - VVTT) x ILOAD (Sourcing)  
The power dissipation of the LP2997 can also be calculated during the shutdown state. During this condition the  
output VTT will tri-state, therefore that term in the power equation will disappear as it cannot sink or source any  
current (leakage is negligible). The only losses during shutdown will be the reduced quiescent current at AVIN  
and the constant impedance that is seen at the VDDQ pin.  
PD = PAVIN + PVDDQ  
PAVIN = IAVIN x VAVIN  
(8)  
(9)  
2
PVDDQ = VVDDQ * IVDDQ = VVDDQ x RVDDQ  
(10)  
Typical Application Circuits  
Several different application circuits have been shown to illustrate some of the options that are possible in  
configuring the LP2997. Graphs of the individual circuit performance can be found in the Typical Performance  
Characteristics section in the beginning of the datasheet. These curves illustrate how the maximum output  
current is affected by changes in AVIN and PVIN.  
Figure 14 shows the recommended circuit configuration for DDR-II applications. The output stage is connected to  
the 1.8V rail and the AVIN pin can be connected to either a 2.5V, 3.3V or 5V rail.  
This circuit permits termination in a minimum amount of board space and component count. Capacitor selection  
can be varied depending on the number of lines terminated and the maximum load transient. However, with  
motherboards and other applications where VTT is distributed across a long plane it is advisable to use multiple  
bulk capacitors and addition to high frequency decoupling. The bulk output capacitors should be situated at both  
ends of the VTT plane for optimal placement. Large aluminum electrolytic capacitors are used for their low ESR  
and low cost.  
LP2997  
VREF = 0.9V  
VREF  
SD  
SD  
+
0.01 mF  
AVIN  
AVIN = 2.5V  
VSENSE  
VTT  
DD  
Q
V
PVIN  
DD  
Q
V
= 1.8V  
VTT = 0.9V  
+
+
22  
mF  
0
GND  
47 mF  
Figure 14. Recommended DDR-II Termination  
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PCB Layout Considerations  
1. The input capacitor for the power rail should be placed as close as possible to the PVIN pin.  
2. VSENSE should be connected to the VTT termination bus at the point where regulation is required. For  
motherboard applications an ideal location would be at the center of the termination bus.  
3. VDDQ can be connected remotely to the VDDQ rail input at either the DIMM or the Chipset. This provides the  
most accurate point for creating the reference voltage.  
4. For improved thermal performance excessive top side copper should be used to dissipate heat from the  
package. Numerous vias from the ground connection to the internal ground plane will help. Additionally these  
can be located underneath the package if manufacturing standards permit.  
5. Care should be taken when routing the VSENSE trace to avoid noise pickup from switching I/O signals. A  
0.1uF ceramic capacitor located close to the  
can also be used to filter any unwanted high frequency  
SENSE  
signal. This can be an issue especially if long SENSE traces are used.  
6. VREF should be bypassed with a 0.01 µF or 0.1 µF ceramic capacitor for improved performance. This  
capacitor should be located as close as possible to the VREF pin.  
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REVISION HISTORY  
Changes from Revision E (April 2013) to Revision F  
Page  
Changed layout of National Data Sheet to TI format ............................................................................................................ 9  
10  
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PACKAGE OPTION ADDENDUM  
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2-Sep-2022  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
95  
95  
95  
95  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LP2997M  
NRND  
SOIC  
SOIC  
D
8
8
8
8
8
8
Non-RoHS  
& Green  
Call TI  
Level-1-235C-UNLIM  
Level-1-260C-UNLIM  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-1-260C-UNLIM  
0 to 125  
0 to 125  
0 to 125  
0 to 125  
0 to 125  
0 to 125  
L2997  
M
LP2997M/NOPB  
LP2997MR  
ACTIVE  
D
RoHS & Green  
SN  
Call TI  
L2997  
M
Samples  
NRND SO PowerPAD  
ACTIVE SO PowerPAD  
ACTIVE SO PowerPAD  
DDA  
DDA  
DDA  
D
Non-RoHS  
& Green  
L2997  
MR  
LP2997MR/NOPB  
LP2997MRX/NOPB  
LP2997MX/NOPB  
RoHS & Green  
NIPDAU | SN  
NIPDAU | SN  
SN  
(L2997, LP2997)  
MR  
Samples  
Samples  
Samples  
2500 RoHS & Green  
2500 RoHS & Green  
(L2997, LP2997)  
MR  
ACTIVE  
SOIC  
L2997  
M
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
2-Sep-2022  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
25-Sep-2022  
TAPE AND REEL INFORMATION  
REEL DIMENSIONS  
TAPE DIMENSIONS  
K0  
P1  
W
B0  
Reel  
Diameter  
Cavity  
A0  
A0 Dimension designed to accommodate the component width  
B0 Dimension designed to accommodate the component length  
K0 Dimension designed to accommodate the component thickness  
Overall width of the carrier tape  
W
P1 Pitch between successive cavity centers  
Reel Width (W1)  
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE  
Sprocket Holes  
Q1 Q2  
Q3 Q4  
Q1 Q2  
Q3 Q4  
User Direction of Feed  
Pocket Quadrants  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LP2997MRX/NOPB  
LP2997MRX/NOPB  
LP2997MX/NOPB  
SO  
PowerPAD  
DDA  
DDA  
D
8
8
8
2500  
2500  
2500  
330.0  
330.0  
330.0  
12.4  
12.5  
12.4  
6.5  
6.4  
6.5  
5.4  
5.2  
5.4  
2.0  
2.1  
2.0  
8.0  
8.0  
8.0  
12.0  
12.0  
12.0  
Q1  
Q1  
Q1  
SO  
PowerPAD  
SOIC  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
25-Sep-2022  
TAPE AND REEL BOX DIMENSIONS  
Width (mm)  
H
W
L
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LP2997MRX/NOPB  
LP2997MRX/NOPB  
LP2997MX/NOPB  
SO PowerPAD  
SO PowerPAD  
SOIC  
DDA  
DDA  
D
8
8
8
2500  
2500  
2500  
356.0  
340.5  
367.0  
356.0  
338.1  
367.0  
35.0  
20.6  
35.0  
Pack Materials-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
25-Sep-2022  
TUBE  
T - Tube  
height  
L - Tube length  
W - Tube  
width  
B - Alignment groove width  
*All dimensions are nominal  
Device  
Package Name Package Type  
Pins  
SPQ  
L (mm)  
W (mm)  
T (µm)  
B (mm)  
LP2997M  
LP2997M  
D
SOIC  
SOIC  
8
8
8
8
8
8
8
8
95  
95  
95  
95  
95  
95  
95  
95  
495  
495  
8
8
8
8
8
8
8
8
4064  
4064  
4064  
4064  
4064  
4064  
630  
3.05  
3.05  
3.05  
3.05  
3.05  
3.05  
4.32  
3.05  
D
LP2997M/NOPB  
LP2997MR  
D
SOIC  
495  
DDA  
DDA  
DDA  
DDA  
DDA  
HSOIC  
HSOIC  
HSOIC  
HSOIC  
HSOIC  
495  
LP2997MR  
495  
LP2997MR/NOPB  
LP2997MR/NOPB  
LP2997MR/NOPB  
495  
507.79  
495  
4064  
Pack Materials-Page 3  
PACKAGE OUTLINE  
DDA0008A  
PowerPADTM SOIC - 1.7 mm max height  
S
C
A
L
E
2
.
4
0
0
PLASTIC SMALL OUTLINE  
C
6.2  
5.8  
TYP  
SEATING PLANE  
PIN 1 ID  
AREA  
A
0.1 C  
6X 1.27  
8
1
2X  
5.0  
4.8  
3.81  
NOTE 3  
4
5
0.51  
8X  
0.31  
4.0  
3.8  
1.7 MAX  
B
0.25  
C A B  
NOTE 4  
0.25  
0.10  
TYP  
SEE DETAIL A  
5
4
EXPOSED  
THERMAL PAD  
0.25  
2.34  
2.24  
GAGE PLANE  
0.15  
0.00  
0 - 8  
1.27  
0.40  
1
8
DETAIL A  
TYPICAL  
2.34  
2.24  
4218825/A 05/2016  
PowerPAD is a trademark of Texas Instruments.  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.15 mm per side.  
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.  
5. Reference JEDEC registration MS-012.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
DDA0008A  
PowerPADTM SOIC - 1.7 mm max height  
PLASTIC SMALL OUTLINE  
(2.95)  
NOTE 9  
SOLDER MASK  
DEFINED PAD  
(2.34)  
SOLDER MASK  
OPENING  
SEE DETAILS  
8X (1.55)  
1
8
8X (0.6)  
(2.34)  
SOLDER MASK  
SYMM  
(1.3)  
TYP  
OPENING  
(4.9)  
NOTE 9  
6X (1.27)  
5
4
(R0.05) TYP  
METAL COVERED  
BY SOLDER MASK  
SYMM  
(5.4)  
(
0.2) TYP  
VIA  
(1.3) TYP  
LAND PATTERN EXAMPLE  
SCALE:10X  
0.07 MIN  
ALL AROUND  
0.07 MAX  
ALL AROUND  
METAL UNDER  
SOLDER MASK  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
4218825/A 05/2016  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
8. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature  
numbers SLMA002 (www.ti.com/lit/slma002) and SLMA004 (www.ti.com/lit/slma004).  
9. Size of metal pad may vary due to creepage requirement.  
10. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown  
on this view. It is recommended that vias under paste be filled, plugged or tented.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
DDA0008A  
PowerPADTM SOIC - 1.7 mm max height  
PLASTIC SMALL OUTLINE  
(2.34)  
BASED ON  
0.125 THICK  
STENCIL  
(R0.05) TYP  
8X (1.55)  
1
8
8X (0.6)  
(2.34)  
SYMM  
BASED ON  
0.125 THICK  
STENCIL  
6X (1.27)  
5
4
METAL COVERED  
BY SOLDER MASK  
SYMM  
(5.4)  
SEE TABLE FOR  
DIFFERENT OPENINGS  
FOR OTHER STENCIL  
THICKNESSES  
SOLDER PASTE EXAMPLE  
EXPOSED PAD  
100% PRINTED SOLDER COVERAGE BY AREA  
SCALE:10X  
STENCIL  
THICKNESS  
SOLDER STENCIL  
OPENING  
0.1  
2.62 X 2.62  
2.34 X 2.34 (SHOWN)  
2.14 X 2.14  
0.125  
0.150  
0.175  
1.98 X 1.98  
4218825/A 05/2016  
NOTES: (continued)  
11. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
12. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
PACKAGE OUTLINE  
DDA0008D  
PowerPADTM SOIC - 1.7 mm max height  
S
C
A
L
E
2
.
4
0
0
PLASTIC SMALL OUTLINE  
C
6.2  
5.8  
TYP  
SEATING PLANE  
PIN 1 ID  
AREA  
A
0.1 C  
6X 1.27  
8
1
2X  
5.0  
4.8  
3.81  
NOTE 3  
4
5
0.51  
8X  
0.31  
4.0  
3.8  
1.7 MAX  
B
0.1  
C A  
B
NOTE 4  
0.25  
0.10  
TYP  
SEE DETAIL A  
5
4
EXPOSED  
THERMAL PAD  
0.25  
2.287  
1.673  
GAGE PLANE  
0.15  
0.00  
0 - 8  
1.27  
0.40  
1
8
DETAIL A  
TYPICAL  
2.287  
1.673  
4218820/A 12/2022  
PowerPAD is a trademark of Texas Instruments.  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.15 mm per side.  
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.  
5. Reference JEDEC registration MS-012, variation BA.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
DDA0008D  
PowerPADTM SOIC - 1.7 mm max height  
PLASTIC SMALL OUTLINE  
(2.95)  
NOTE 9  
SOLDER MASK  
DEFINED PAD  
(2.287)  
SOLDER MASK  
OPENING  
SEE DETAILS  
8X (1.55)  
1
8
8X (0.6)  
(4.9)  
NOTE 9  
SYMM  
(2.287)  
(1.3)  
SOLDER MASK  
TYP  
OPENING  
6X (1.27)  
5
4
(
0.2) TYP  
VIA  
SYMM  
(5.4)  
(R0.05) TYP  
METAL COVERED  
BY SOLDER MASK  
(1.3) TYP  
LAND PATTERN EXAMPLE  
SCALE:10X  
0.07 MAX  
ALL AROUND  
0.07 MIN  
ALL AROUND  
METAL UNDER  
SOLDER MASK  
SOLDER MASK  
OPENING  
METAL  
SOLDER MASK  
OPENING  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
4218820/A 12/2022  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
8. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature  
numbers SLMA002 (www.ti.com/lit/slma002) and SLMA004 (www.ti.com/lit/slma004).  
9. Size of metal pad may vary due to creepage requirement.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
DDA0008D  
PowerPADTM SOIC - 1.7 mm max height  
PLASTIC SMALL OUTLINE  
(2.287)  
BASED ON  
0.125 THICK  
STENCIL  
8X (1.55)  
(R0.05) TYP  
1
8
8X (0.6)  
(2.287)  
BASED ON  
0.127 THICK  
STENCIL  
SYMM  
6X (1.27)  
5
4
METAL COVERED  
BY SOLDER MASK  
SEE TABLE FOR  
SYMM  
(5.4)  
DIFFERENT OPENINGS  
FOR OTHER STENCIL  
THICKNESSES  
SOLDER PASTE EXAMPLE  
EXPOSED PAD  
100% PRINTED SOLDER COVERAGE BY AREA  
SCALE:10X  
STENCIL  
THICKNESS  
SOLDER STENCIL  
OPENING  
0.1  
2.557 X 2.557  
2.287 X 2.287 (SHOWN)  
2.088 X 2.088  
0.125  
0.150  
0.175  
1.933 X 1.933  
4218820/A 12/2022  
NOTES: (continued)  
10. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
11. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
PACKAGE OUTLINE  
D0008A  
SOIC - 1.75 mm max height  
SCALE 2.800  
SMALL OUTLINE INTEGRATED CIRCUIT  
C
SEATING PLANE  
.228-.244 TYP  
[5.80-6.19]  
.004 [0.1] C  
A
PIN 1 ID AREA  
6X .050  
[1.27]  
8
1
2X  
.189-.197  
[4.81-5.00]  
NOTE 3  
.150  
[3.81]  
4X (0 -15 )  
4
5
8X .012-.020  
[0.31-0.51]  
B
.150-.157  
[3.81-3.98]  
NOTE 4  
.069 MAX  
[1.75]  
.010 [0.25]  
C A B  
.005-.010 TYP  
[0.13-0.25]  
4X (0 -15 )  
SEE DETAIL A  
.010  
[0.25]  
.004-.010  
[0.11-0.25]  
0 - 8  
.016-.050  
[0.41-1.27]  
DETAIL A  
TYPICAL  
(.041)  
[1.04]  
4214825/C 02/2019  
NOTES:  
1. Linear dimensions are in inches [millimeters]. Dimensions in parenthesis are for reference only. Controlling dimensions are in inches.  
Dimensioning and tolerancing per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed .006 [0.15] per side.  
4. This dimension does not include interlead flash.  
5. Reference JEDEC registration MS-012, variation AA.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
D0008A  
SOIC - 1.75 mm max height  
SMALL OUTLINE INTEGRATED CIRCUIT  
8X (.061 )  
[1.55]  
SYMM  
SEE  
DETAILS  
1
8
8X (.024)  
[0.6]  
SYMM  
(R.002 ) TYP  
[0.05]  
5
4
6X (.050 )  
[1.27]  
(.213)  
[5.4]  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE:8X  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
METAL  
EXPOSED  
METAL  
EXPOSED  
METAL  
.0028 MAX  
[0.07]  
.0028 MIN  
[0.07]  
ALL AROUND  
ALL AROUND  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
4214825/C 02/2019  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
D0008A  
SOIC - 1.75 mm max height  
SMALL OUTLINE INTEGRATED CIRCUIT  
8X (.061 )  
[1.55]  
SYMM  
1
8
8X (.024)  
[0.6]  
SYMM  
(R.002 ) TYP  
[0.05]  
5
4
6X (.050 )  
[1.27]  
(.213)  
[5.4]  
SOLDER PASTE EXAMPLE  
BASED ON .005 INCH [0.125 MM] THICK STENCIL  
SCALE:8X  
4214825/C 02/2019  
NOTES: (continued)  
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
9. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
IMPORTANT NOTICE AND DISCLAIMER  
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, regulatory or other requirements.  
These resources are subject to change without notice. TI grants you permission to use these resources only for development of an  
application that uses the TI products described in the resource. Other reproduction and display of these resources is prohibited. No license  
is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you  
will fully indemnify TI and its representatives against, any claims, damages, costs, losses, and liabilities arising out of your use of these  
resources.  
TI’s products are provided subject to TI’s Terms of Sale or other applicable terms available either on ti.com or provided in conjunction with  
such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable warranties or warranty disclaimers for  
TI products.  
TI objects to and rejects any additional or different terms you may have proposed. IMPORTANT NOTICE  
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2022, Texas Instruments Incorporated  

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