LP2986
Micropower, 200 mA Ultra Low-Dropout Fixed or
Adjustable Voltage Regulator
LP2986 Micropower, 200 mA Ultra Low-Dropout Fixed or Adjustable Voltage Regulator
March 2005
General Description
The LP2986 is a 200 mA precision LDO voltage regulator
which offers the designer a higher performance version of
the industry standard LP2951.
™
Using an optimized VIP
cess, the LP2986 delivers superior performance:
Dropout Voltage: Typically 180 mV
@
1 mA load.
mV
Ground Pin Current: Typically 1 mA
@
200 µA
Sleep Mode: The LP2986 draws less than 1 µA quiescent
current when shutdown pin is pulled low.
Error Flag: The built-in error flag goes low when the output
drops approximately 5% below nominal.
Precision Output: The standard product versions available
can be pin-strapped (using the internal resistive divider) to
provide output voltages of 5.0V, 3.3V, or 3.0V with guaranteed accuracy of 0.5% (“A” grade) and 1% (standard grade)
at room temperature.
10 mA load.
(Vertically Integrated PNP) pro-
@
200 mA load, and 1
@
200 mA load, and
Block Diagram
Features
n Ultra low dropout voltage
n Guaranteed 200 mA output current
n SO-8 and mini-SO8 surface mount packages
<
n
1 µA quiescent current when shutdown
n Low ground pin current at all loads
n 0.5% output voltage accuracy (“A” grade)
n High peak current capability (400 mA typical)
n Wide supply voltage range (16V max)
n Overtemperature/overcurrent protection
n −40˚C to +125˚C junction temperature range
Applications
n Cellular Phone
n Palmtop/Laptop Computer
n Camcorder, Personal Stereo, Camera
01293501
VIP™is a trademark of National Semiconductor Corporation.
© 2005 National Semiconductor Corporation DS012935 www.national.com
Connection Diagrams and Ordering Information
LP2986
Surface Mount Packages: 8-Lead LLP Surface Mount Package
SO-8/Mini SO-8 Package
01293502
See NS Package Drawing Number M08A/MUA08A
Basic Application Circuits
Application Using Internal Resistive Divider
Top View
01293543
See NS Package Drawing Number LDC08A
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01293503
Basic Application Circuits (Continued)
Application Using External Divider
LP2986
Ordering Information
TABLE 1. Package Marking and Ordering Information
Output Voltage Grade Order Information Package Marking Supplied as:
Mini SO-8
5 A LP2986AIMMX-5.0 L41A 3500 Units on Tape and
5 A LP2986AIMM-5.0 L41A 1000 Units on Tape and
5 STD LP2986IMMX-5.0 L41B 3500 Units on Tape and
5 STD LP2986IMM-5.0 L41B 1000 Units on Tape and
3.3 A LP2986AIMMX-3.3 L40A 3500 Units on Tape and
3.3 A LP2986AIMM-3.3 L40A 1000 Units on Tape and
3.3 STD LP2986IMMX-3.3 L40B 3500 Units on Tape and
3.3 STD LP2986IMM-3.3 L40B 1000 Units on Tape and
3.0 A LP2986AIMMX-3.0 L39A 3500 Units on Tape and
3.0 A LP2986AIMM-3.0 L39A 1000 Units on Tape and
3.0 STD LP2986IMMX-3.0 L39B 3500 Units on Tape and
3.0 STD LP2986IMM-3.0 L39B 1000 Units on Tape and
01293504
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
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Ordering Information (Continued)
LP2986
Output Voltage Grade Order Information Package Marking Supplied as:
SO-8
5 A LP2986AIMX-5.0 2986AIM5.0 2500 Units on Tape and
5 A LP2986AIM-5.0 2986AIM5.0 Shipped in Anti-Static
5 STD LP2986IMX-5.0 2986IM5.0 2500 Units on Tape and
5 STD LP2986IM-5.0 2986IM5.0 Shipped in Anti-Static
3.3 A LP2986AIMX-3.3 2986AIM3.3 2500 Units on Tape and
3.3 A LP2986AIM-3.3 2986AIM3.3 Shipped in Anti-Static
3.3 STD LP2986IMX-3.3 2986IM3.3 2500 Units on Tape and
3.3 STD LP2986IM-3.3 2986IM3.3 Shipped in Anti-Static
3.0 A LP2986AIMX-3.0 2986AIM3.0 2500 Units on Tape and
3.0 A LP2986AIM-3.0 2986AIM3.0 Shipped in Anti-Static
3.0 STD LP2986IMX-3.0 2986IM3.0 2500 Units on Tape and
3.0 STD LP2986IM-3.0 2986IM3.0 Shipped in Anti-Static
8-Lead LLP
5 A LP2986AILD-5 L006A 1000 Units on Tape and
5 A LP2986AILDX-5 L006A 4500 Units on Tape and
5 STD LP2986ILD-5 L006AB 1000 Units on Tape and
5 STD LP2986ILDX-5 L006AB 4500 Units on Tape and
3.3 A LP2986AILD-3.3 L005A 1000 Units on Tape and
3.3 A LP2986AILDX-3.3 L005A 4500 Units on Tape and
3.3 STD LP2986ILD-3.3 L005AB 1000 Units on Tape and
3.3 STD LP2986ILDX-3.3 L005AB 4500 Units on Tape and
3.0 A LP2986AILD-3.0 L004A 1000 Units on Tape and
3.0 A LP2986AILDX-3.0 L004A 4500 Units on Tape and
3.0 STD LP2986ILD-3.0 L004AB 1000 Units on Tape and
3.0 STD LP2986ILDX-3.0 L004AB 4500 Units on Tape and
TABLE 1. Package Marking and Ordering Information (Continued)
Reel
Rails
Reel
Rails
Reel
Rails
Reel
Rails
Reel
Rails
Reel
Rails
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
Reel
www.national.com 4
LP2986
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range −65˚C to +150˚C
Operating Junction
Temperature Range −40˚C to +125˚C
Lead Temperature
(Soldering, 5 seconds) 260˚C
ESD Rating (Note 2) 2 kV
Power Dissipation (Note 3) Internally Limited
Input Supply Voltage
(Survival) −0.3V to +16V
Input Supply Voltage
(Operating) 2.1V to +16V
Shutdown Pin −0.3V to +16V
Feedback Pin −0.3V to +5V
Output Voltage
(Survival) (Note 4) −0.3V to +16V
I
(Survival) Short Circuit Protected
OUT
Input-Output Voltage
(Survival) (Note 5) −0.3V to +16V
Electrical Characteristics
Limits in standard typeface are for TJ= 25˚C, and limits in boldface type apply over the full operating temperature range. Unless otherwise specified: V
(NOM) + 1V, IL= 1 mA, C
IN=VO
Symbol Parameter Conditions Typical
V
O
Output Voltage
(5.0V Versions)
0.1 mA
<
<
I
200 mA
L
Output Voltage
(3.3V Versions)
0.1 mA
<
<
I
200 mA
L
Output Voltage
(3.0V Versions)
Output Voltage Line
Regulation
0.1 mA
VO(NOM) + 1V ≤ VIN≤
16V
<
<
I
200 mA
L
= 4.7 µF, CIN= 2.2 µF, V
OUT
5.0 4.975 5.025 4.950 5.050
5.0
3.3 3.283 3.317 3.267 3.333
3.3
3.0 2.985 3.015 2.970 3.030
3.0
0.007
= 2V.
S/D
LM2986AI-X.X
(Note 6)
LM2986I-X.X
(Note 6)
Min Max Min Max
4.960 5.040 4.920 5.080
4.910 5.090 4.860 5.140
3.274 3.326 3.247 3.353
3.241 3.359 3.208 3.392
2.976 3.024 2.952 3.048
2.946 3.054 2.916 3.084
0.014 0.014
0.032 0.032
Units
V
%/V
V
IN–VO
Dropout Voltage
IL= 100 µA
(Note 7)
=75mA
I
L
I
= 200 mA
L
I
GND
I
(PK) Peak Output Current V
O
I
(MAX) Short Circuit Current RL= 0 (Steady State)
O
Ground Pin Current IL= 100 µA
I
=75mA
L
I
= 200 mA
L
<
V
0.3V 0.05 1.5 1.5 µA
S/D
≥ VO(NOM) − 5% 400 250 250
OUT
(Note 11)
e
n
Output Noise Voltage
(RMS)
Ripple Rejection f = 1 kHz, C
Output Voltage
BW = 300 Hz to 50 kHz,
=10µF
C
OUT
OUT
(Note 9)
Temperature Coefficient
=10µF
1
90
180
100
500
1
400
2.0 2.0
3.5 3.5
120 120
170 170
230 230
350 350
120 120
150 150
800 800
1400 1400
2.1 2.1
3.7 3.7
mV
µA
mA
mA
160 µV(RMS)
65 dB
20 ppm/˚C
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Electrical Characteristics (Continued)
LP2986
Limits in standard typeface are for TJ= 25˚C, and limits in boldface type apply over the full operating temperature range. Unless otherwise specified: V
(NOM) + 1V, IL= 1 mA, C
IN=VO
Symbol Parameter Conditions Typical
FEEDBACK PIN
V
FB
Feedback Pin Voltage
(Note 10) 1.23 1.19 1.28 1.18 1.29
FB Pin Voltage
(Note 9)
Temperature Coefficient
= 4.7 µF, CIN= 2.2 µF, V
OUT
1.23
20 ppm/˚C
= 2V.
S/D
LM2986AI-X.X
(Note 6)
LM2986I-X.X
(Note 6)
Min Max Min Max
1.21 1.25 1.20 1.26
Units
V1.20 1.26 1.19 1.27
I
FB
Feedback Pin Bias
Current
FB Pin Bias Current
Temperature Coefficient
IL= 200 mA
(Note 9)
150
0.1 nA/˚C
SHUTDOWN INPUT
V
S/D
I
S/D
S/D Input Voltage
(Note 8)
S/D Input Current V
VH= O/P ON 1.4 1.6 1.6
V
= O/P OFF 0.55 0.18 0.18
L
=0 0 −1 −1
S/D
V
=5V 5 15 15
S/D
ERROR COMPARATOR
I
OH
V
OL
V
THR
(MAX)
V
THR
(MIN)
Output “HIGH” Leakage VOH= 16V
Output “LOW” Voltage VIN=VO(NOM) − 0.5V,
(COMP) = 300 µA
I
O
Upper Threshold Voltage
Lower Threshold Voltage
0.01
150
−4.6
−6.6
HYST Hysteresis 2.0
330 330
760 760
11
22
220 220
350 350
−5.5 −3.5 −5.5 −3.5
−7.7 −2.5 −7.7 −2.5
−8.9 −4.9 −8.9 −4.9
−13.0 −3.3 −13.0 −3.3
%V
nA
V
µA
µA
mV
OUT
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Electrical Characteristics (Continued)
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the
device outside of its rated operating conditions.
Note 2: The ESD rating of the Feedback pin is 500V. The ESD rating of the V
Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, T
and the ambient temperature, T
. The maximum allowable power dissipation at any ambient temperature is calculated using:
A
pin is 1kV and the Tap pin is 1.5 kV.
IN
(MAX), the junction-to-ambient thermal resistance, θ
J
J−A
LP2986
,
The value of θ
dependent on PCB trace area, trace material, and the number of layers and thermal vias. For improved thermal resistance and power dissipation for the LLP
for the SO-8 (M) package is 160˚C/W, and the mini SO-8 (MM) package is 200˚C/W. The value θ
J−A
for the LLP (LD) package is specifically
J−A
package, refer to Application Note AN-1187. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into
thermal shutdown.
Note 4: If used in a dual-supply system where the regulator load is returned to a negative supply, the LM2986 output must be diode-clamped to ground.
Note 5: The output PNP structure contains a diode between the V
turn on this diode and may induce a latch-up mode which can damage the part (see Application Hints).
IN
and V
terminals that is normally reverse-biased. Forcing the output above the input will
OUT
Note 6: Limits are 100% production tested at 25˚C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control
(SQC) methods. The limits are used to calculate National’s Average Outgoing Quality Level (AOQL).
Note 7: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a 1V differential.
Note 8: To prevent mis-operation, the Shutdown input must be driven by a signal that swings above V
Application Hints).
and below VLwith a slew rate not less than 40 mV/µs (see
H
Note 9: Temperature coefficient is defined as the maximum (worst-case) change divided by the total temperature range.
≤ V
Note 10: V
FB
≤ (VIN− 1), 2.5V ≤ VIN≤ 16V, 100 µA ≤ IL≤ 200 mA, TJ≤ 125˚C.
OUT
Note 11: See Typical Performance Characteristics curves.
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Typical Performance Characteristics Unless otherwise specified: T
= 2.2 µF, S/D is tied to VIN,VIN=VO(NOM) + 1V, IL= 1 mA.
C
IN
LP2986
vs Temperature Dropout Voltage vs Temperature
V
OUT
= 25˚C, C
A
OUT
= 4.7 µF,
01293508
01293509
Dropout Voltage vs Load Current Dropout Characteristics
01293510
01293513
Ground Pin Current vs Temperature and Load Ground Pin Current vs Load Current
01293512
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01293511
LP2986
Typical Performance Characteristics Unless otherwise specified: T
= 2.2 µF, S/D is tied to VIN,VIN=VO(NOM) + 1V, IL= 1 mA. (Continued)
C
IN
Input Current vs V
IN
01293514
Load Transient Response Load Transient Response
Input Current vs V
= 25˚C, C
A
OUT
IN
= 4.7 µF,
01293515
01293516 01293517
Line Transient Response Line Transient Response
01293518 01293520
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Typical Performance Characteristics Unless otherwise specified: T
= 2.2 µF, S/D is tied to VIN,VIN=VO(NOM) + 1V, IL= 1 mA. (Continued)
C
IN
LP2986
Turn-On Waveform Turn-Off Waveform
= 25˚C, C
A
OUT
= 4.7 µF,
01293521
01293523
Short Circuit Current Short Circuit Current
01293524 01293525
Short Circuit Current vs Output Voltage Instantaneous Short Circuit Current vs Temperature
01293526
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01293527
LP2986
Typical Performance Characteristics Unless otherwise specified: T
= 2.2 µF, S/D is tied to VIN,VIN=VO(NOM) + 1V, IL= 1 mA. (Continued)
C
IN
DC Load Regulation Feedback Bias Current vs Load
01293528
Feedback Bias Current vs Temperature Shutdown Pin Current vs Shutdown Pin Voltage
= 25˚C, C
A
OUT
= 4.7 µF,
01293529
01293530
01293531
Shutdown Voltage vs Temperature Input to Output Leakage vs Temperature
01293532
01293537
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Typical Performance Characteristics Unless otherwise specified: T
= 2.2 µF, S/D is tied to VIN,VIN=VO(NOM) + 1V, IL= 1 mA. (Continued)
C
IN
LP2986
Output Noise Density Output Impedance vs Frequency
= 25˚C, C
A
OUT
= 4.7 µF,
01293534
Output Impedance vs Frequency Ripple Rejection
01293536
Application Hints
LLP Package Devices
The LP2986 is offered in the 8 lead LLP surface mount
package to allow for increased power dissipation compared
to the SO-8 and Mini SO-8. For details on thermal performance as well as mounting and soldering specifications,
refer to Application Note AN-1187.
01293535
01293533
Curves are provided which show the allowable ESR range
as a function of load current for various output voltages and
capacitor values (see ESR curves below).
ESR Curves For 5V Output
EXTERNAL CAPACITORS
Like any low-dropout regulator, external capacitors are required to assure stability. These capacitors must be correctly
selected for proper performance.
INPUT CAPACITOR: An input capacitor (≥ 2.2 µF) is re-
quired between the LP2986 input and ground (amount of
capacitance may be increased without limit).
This capacitor must be located a distance of not more than
0.5” from the input pin and returned to a clean analog
ground. Any good quality ceramic or tantalum may be used
for this capacitor.
OUTPUT CAPACITOR: The output capacitor must meet the
requirement for minimum amount of capacitance and also
have an appropriate E.S.R. (equivalent series resistance)
value.
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01293506
Application Hints (Continued)
ESR Curves For 2.5V Output
01293507
IMPORTANT: The output capacitor must maintain its ESR in
the stable region over the full operating temperature range of
the application to assure stability.
The minimum required amount of output capacitance is
4.7 µF. Output capacitor size can be increased without limit.
It is important to remember that capacitor tolerance and
variation with temperature must be taken into consideration
when selecting an output capacitor so that the minimum
required amount of output capacitance is provided over the
full operating temperature range. A good Tantalum capacitor
will show very little variation with temperature, but a ceramic
may not be as good (see next section).
CAPACITOR CHARACTERISTICS
TANTALUM: The best choice for size, cost, and perfor-
mance are solid tantalum capacitors. Available from many
sources, their typical ESR is very close to the ideal value
required on the output of many LDO regulators.
Tantalums also have good temperature stability: a 4.7 µF
was tested and showed only a 10% decline in capacitance
as the temperature was decreased from +125˚C to −40˚C.
The ESR increased only about 2:1 over the same range of
temperature.
However, it should be noted that the increasing ESR at lower
temperatures present in all tantalums can cause oscillations
when marginal quality capacitors are used (where the ESR
of the capacitor is near the upper limit of the stability range at
room temperature).
CERAMIC: For a given amount of a capacitance, ceramics
are usually larger and more costly than tantalums.
Be warned that the ESR of a ceramic capacitor can be low
enough to cause instability: a 2.2 µF ceramic was measured
and found to have an ESR of about 15 mΩ.
If a ceramic capacitor is to be used on the LP2986 output, a
1Ω resistor should be placed in series with the capacitor to
provide a minimum ESR for the regulator.
Another disadvantage of ceramic capacitors is that their
capacitance varies a lot with temperature:
Large ceramic capacitors are typically manufactured with the
Z5U temperature characteristic, which results in the capacitance dropping by a 50% as the temperature goes from 25˚C
to 80˚C.
This means you have to buy a capacitor with twice the
minimum C
to assure stable operation up to 80˚C.
OUT
ALUMINUM: The large physical size of aluminum electrolytics makes them unattractive for use with the LP2986. Their
ESR characteristics are also not well suited to the requirements of LDO regulators.
The ESR of an aluminum electrolytic is higher than a tantalum, and it also varies greatly with temperature.
A typical aluminum electrolytic can exhibit an ESR increase
of 50X when going from 20˚C to −40˚C. Also, some aluminum electrolytics can not be used below −25˚C because the
electrolyte will freeze.
USING AN EXTERNAL RESISTIVE DIVIDER
The LP2986 output voltage can be programmed using an
external resistive divider (see Basic Application Circuits).
The resistor connected between the Feedback pin and
ground should be 51.1k. The value for the other resistor (R1)
connected between the Feedback pin and the regulated
output is found using the formula:
= 1.23 x (1 + R1/51.1k)
V
OUT
It should be noted that the 25 µA of current flowing through
the external divider is approximately equal to the current
saved by not connecting the internal divider, which means
the quiescent current is not increased by using external
resistors.
A lead compensation capacitor (C
) must also be used to
F
place a zero in the loop response at about 50 kHz. The value
can be found using:
for C
F
= 1/(2π x R1 x 50k)
C
F
A good quality capacitor must be used for C
to ensure that
F
the value is accurate and does not change significantly over
temperature. Mica or ceramic capacitors can be used, as-
±
suming a tolerance of
20% or better is selected.
If a ceramic is used, select one with a temperature coefficient of NPO, COG, Y5P, or X7R. Capacitor types Z5U, Y5V,
and Z4V can not be used because their value varies more
that 50% over the −25˚C to +85˚C temperature range.
SHUTDOWN INPUT OPERATION
The LP2986 is shut off by driving the Shutdown input low,
and turned on by pulling it high. If this feature is not to be
used, the Shutdown input should be tied to V
to keep the
IN
regulator output on at all times.
To assure proper operation, the signal source used to drive
the Shutdown input must be able to swing above and below
the specified turn-on/turn-off voltage thresholds listed as V
and VL, respectively (see Electrical Characteristics).
It is also important that the turn-on (and turn-off) voltage
signals applied to the Shutdown input have a slew rate which
is not less than 40 mV/µs.
CAUTION: the regulator output state can not be guaranteed
if a slow-moving AC (or DC) signal is applied that is in the
range between V
and VL.
H
REVERSE INPUT-OUTPUT VOLTAGE
The PNP power transistor used as the pass element in the
LP2986 has an inherent diode connected between the regulator output and input.
During normal operation (where the input voltage is higher
than the output) this diode is reverse-biased.
However, if the output is pulled above the input, this diode
will turn ON and current will flow into the regulator output.
LP2986
H
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Application Hints (Continued)
LP2986
In such cases, a parasitic SCR can latch which will allow a
high current to flow into V
can damage the part.
(and out the ground pin), which
IN
In any application where the output may be pulled above the
input, an external Schottky diode must be connected from
to V
V
IN
(cathode on VIN, anode on V
OUT
), to limit the
OUT
reverse voltage across the LP2986 to 0.3V (see Absolute
Maximum Ratings).
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Physical Dimensions inches (millimeters)
unless otherwise noted
LP2986
8-Lead Mini-Small Outline Molded Package, JEDEC
NS Package Number MUA08A
8-Lead (0.150” Wide) Molded Small Outline Package, JEDEC
NS Package Number M08A
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
8-Lead LLP Surface Mount Package
NS Package Number LDC08A
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.
For the most current product information visit us at www.national.com.
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NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS
WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body, or
(b) support or sustain life, and whose failure to perform when
properly used in accordance with instructions for use
2. A critical component is any component of a life support
device or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
provided in the labeling, can be reasonably expected to result
in a significant injury to the user.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products
LP2986 Micropower, 200 mA Ultra Low-Dropout Fixed or Adjustable Voltage Regulator
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain
no ‘‘Banned Substances’’ as defined in CSP-9-111S2.
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