ETC THAT1512S08-U

Low-Noise, High Performance
Audio Preamplifier IC
THAT 1510, 1512
FEATURES
APPLICATIONS
• Low Noise:
1 nV/√Hz input noise (60dB gain)
34 nV/√Hz input noise (0dB gain) (1512)
• Differential Low Noise Preamplifiers
• Low THD+N (full audio bandwidth):
0.001% ≤ 40 dB gain
0.005% @ 60 dB gain
• Differential Variable Gain Amplifiers
• Differential Summing Amplifiers
• Microphone Preamplifiers
• Low Current: 6mA typ.
• Moving-Coil Transducer Amplifiers
• Wide Bandwidth: 7MHz @ G=100
• High Slew Rate: 19 V/μs
• Line Input Stages
• Wide Output Swing: ±13.3V on
±15V supplies
• Audio
• Gain adjustable from 0 to >60 dB with
one external resistor
• Sonar
• Industry Standard Pinouts
• Instrumentation
Description
The THAT 1510 and 1512 are high performance audio preamplifiers suitable for microphone
preamp and bus summing applications. The ICs
are available in a variety of packages and pin
configurations, making them pin compatible with
the Analog Devices SSM2019 and SSM2017
(discontinued), and the Texas Instruments
INA217 and INA163.
Gain for both parts is adjustable via one
external resistor, making it possible to control
gain over a wide range with a single-gang potentiometer. The 1510 gain equation is identical to
that of the SSM 2019, reaching 6 dB gain with a
10 kΩ resistor. The 1512 reaches 0 dB gain with
a 10 kΩ resistor. Because the 1512 exhibits
Input Stage
Designed from the ground up in THAT’s
complementary dielectric isolation process and
including laser-trimmed Si-Chrome thin film
resistors, the THAT 1510 and 1512 improve on
existing integrated microphone preamps by offering lower noise at low gains, wider bandwidth,
higher slew rate, lower distortion, and lower
supply current. The parts feature internal ESD
overload protection on all critical pins.
In short, the THAT 1510 and 1512 provide
superior performance in a popular format at an
affordable price.
Output Stage
V+
5k
(10k)
-AV
-AV
+In
-In
significantly lower noise at lower gain settings, it
is recommended over the 1510 for new designs.
5k
(10k)
RA
5k
5k
+
Out
5k
Ref
Pin
Name
RG1
-In
+In
VRef
Out
V+
RG2
DIP8
Pkg
1
2
3
4
5
6
7
8
SO8
Pkg
1
2
3
4
5
6
7
8
SO16
Pkg
2
4
5
7
10
11
13
15
SO14
Pkg
3
4
5
6
10
9
11
12
Table 1. Pin Assignments
RG1
R G2
RB
5k
Part
Type
DIP8
Pkg
SO8
Pkg
SO16
Pkg
SO14
Pkg
1510 1510P08-U 1510S08-U 1510W16-U 1510S14-U
V-
1512 1512P08-U 1512S08-U
Figure 1. THAT 1510 / 1512 Equivalent Circuit Diagram
(THAT 1512 values shown in parentheses)
Inquire
1512S14-U
Table 2. Ordering Information
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation. Document 600031 Rev 08
Document 600031 Rev 08
Page 2 of 8
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier IC
SPECIFICATIONS 1
Absolute Maximum Ratings 2,3
Positive Supply Voltage (VCC)
Negative Supply Voltage (VEE)
Input Voltage (VIN MAX)
+20 V
Lead Temp. (TLEAD) (Soldering 10 sec)
-20 V
Operating Temperature Range (TOP)
-40 to +85°C
Storage Temperature Range (TST)
VCC + 0.5V, VEE - 0.5V
Output Short-Circuit Duration (tSH)
260 °C
-40 to +125°C
Junction Temperature (TJ)
Continuous
150°C
Recommended Operating Conditions
Parameter
Symbol
Conditions
Min
Typ
Max
Units
Positive Supply Voltage
VCC
+5
+20
V
Negative Supply Voltage
VEE
-5
-20
V
Electrical Characteristics 2
Parameter
Symbol
Conditions
Min
1510
Typ
Max
Min
1512
Typ
Max
Units
Supply Current
ICC, -IEE
No signal
VCC = -VEE = 20V
—
—
6.0
—
7.9
8.0
—
—
6.0
—
7.9
8.0
mA
mA
IB
No signal; Either input
connected to GND
—
4.8
14
—
4.8
14
µA
Input Offset Current
IB-OFF
No signal
-1.4
—
+1.4
-1.4
—
+1.4
µA
Offset Voltage
Output Stage Output Offset
Input Stage Input Offset
Total Output Offset
VosOO
VosII
No Signal, VCM=0
Input Bias Current
Input Voltage Range
Common Mode
G=voltage gain
—
—
± 13
—
V
—
+13
-13
—
+13
V
0
—
70
-6
—
64
dB
Ref Input Voltage Range
—
±8
—
—
±8
—
V
Ref Input Impedance
—
10
—
—
15
—
kΩ
Ref Input Gain to Output
—
0
—
—
0
—
dB
—
—
—
—
32||1.9
32||2.0
32||2.5
29||8.0
—
—
—
—
— 37||1.9
— 37||2.0
— 36||3.1
— 31||13.9
—
—
—
—
MΩ||pF
MΩ||pF
MΩ||pF
MΩ||pF
—
8||7.7
—
—
—
MΩ||pF
Differential Mode
Differential Gain
Input Impedance
VIN-UNBAL
Unbalanced
-13
One input to GND, 0dB gain
Gdiff
ZIN-DIFF
ZIN-CM
—
mV
µV
mV
± 13
VIN-CM
Common mode, all gains
-5
—
+5
-5
—
+5
-250
—
+250
-250
—
+250
-5-0.25G
5+0.25G -5-0.25G
5+0.25G
Differential
0dB gain
20dB gain
40dB gain
60dB gain
Common mode
all gains
9||7.7
1. All specifications are subject to change without notice.
2. Unless otherwise noted, T A=25ºC, VCC=+15V, VEE= -15V.
3. Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only; the functional operation of
the device at these or any other conditions above those indicated in the operational sections of this specification is not impli ed. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier
Page 3 of 8
Document 600031 Rev 08
Electrical Characteristics (con’t) 2
Parameter
Symbol
Conditions
Min
1510
Typ
Max
Min
1512
Typ
Max
CMR
VCM =± 10V; DC to 60 Hz
0 dB gain
20 dB gain
40 dB gain
60 dB gain
45
65
85
105
60
80
100
120
—
—
—
—
45
65
85
105
60
80
100
120
—
—
—
—
dB
dB
dB
dB
85
105
120
124
—
—
—
—
—
—
—
—
60
105
120
124
—
—
—
—
dB
dB
dB
dB
Common Mode Rejection
Power Supply Rejection
PSR
Total Harmonic Distortion
VCC= -VEE; ±5V to ±20V; DC to 60 Hz
0 dB gain
—
20 dB gain
—
40 dB gain
—
60 dB gain
—
THD+N
en(IN)
Equivalent Input Noise
Units
VOUT = 7Vrms; RL = 5 kΩ
f = 1kHz; BW = 20 kHz
0 dB gain
20 dB gain
40 dB gain
60 dB gain
—
—
—
—
0.0005
0.0012
0.0016
0.005
—
—
—
—
—
—
—
—
0.001
0.004
0.005
0.008
—
—
—
—
%
%
%
%
f = 1kHz,
0 dB gain
20 dB gain
40 dB gain
60 dB gain
—
—
—
—
57
7
1.7
1
—
—
—
—
—
—
—
—
34
4.6
1.4
1
—
—
—
nV/√Hz
nV/√Hz
nV/√Hz
nV/√Hz
Input Current Noise
in(IN)
60 dB gain
—
2.0
—
—
2.0
—
pA/√Hz
Noise Figure
NF
60 dB gain
RS = 150 Ω
RS = 200 Ω
—
—
1.6
1.3
—
—
—
—
1.6
1.3
—
—
dB
dB
RL = 2 kΩ
CL = 50 pF
13
19
—
13
19
—
V/µs
RL = 2 kΩ; CL = 10 pF
0 dB gain
20 dB gain
40 dB gain
60 dB gain
—
—
—
—
15
8
7
3
—
—
—
—
—
—
—
—
11
9
7
1.6
—
—
—
MHz
MHz
MHz
MHz
f = 1kHz; RL = 2 kΩ
RG =infinite, G=0 dB
RG = 1.1 kΩ, G=20 dB
RG = 101 Ω, G=40 dB
RG = 10 Ω, G=60 dB
RG = 10 kΩ, G=0 dB
RG = 526.3 Ω, G=20 dB
RG = 50.3 Ω, G=40 dB
RG = 5 Ω, G=60 dB
-0.5
-0.5
-0.5
-0.5
—
—
—
—
—
—
—
—
—
—
—
—
+0.5
+0.5
+0.5
+0.5
—
—
—
—
—
—
—
—
-0.5
-0.5
-0.5
-0.5
—
—
—
—
—
—
—
—
—
—
—
—
+0.5
+0.5
+0.5
+0.5
dB
dB
dB
dB
dB
dB
dB
dB
RL = 2 kΩ
all gains
±13
±13.3
—
±13
±13.3
—
V
RL = 0 Ω
—
± 17
—
—
± 17
—
mA
Slew Rate
SR
Bandwidth -3dB
BW-3dB
Output Gain Error
GER (OUT)
Output Voltage Swing
VO
Output Short Circuit Current
ISC
Minimum Resistive Load
RLmin
2
—
—
2
—
—
kΩ
Maximum Capacitive Load
CLmax
—
—
300
—
—
300
pF
Gain Equation
AV = 1 + 10Rk
G
AV = 0.5 + 5Rk
G
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation
Document 600031 Rev 08
Page 4 of 8
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier IC
Applications
critical, a potentiometer may be used. In such applications, designers should take care in specifying the
element construction to avoid excess noise. The
potentiometer taper will set the circuit’s characteristic of gain vs. pot rotation. Typically, reverse log
(reverse audio) taper elements offer the desired
behavior in which gain increases with clockwise
rotation (and lower values for RG). See THAT Design
Note 138 for a discussion of potentiometer taper and
gain for the 1510 and 1512 compared to similar
parts from other manufacturers.
Gain Setting
A single external resistor (RG) between the RG1
and RG2 pins is all that is needed to set the gain of the
THAT 1510/1512, according to the formulae:
for the 1510:
AV = 1 + 10k
RG
for the 1512:
AV = 0.5 + 5k
RG
or
where
AV is the voltage gain of the part.
Either part may reach unity gain, but the value
of RG required varies significantly between the two
parts. For the 1510, gain is 0dB when RG is infinite
(open); this is the minimum gain for the 1510. At
infinite RG, the 1512 reaches -6dB gain; this is the
minimum gain for the 1512. With RG=10kΩ, the
1512 reaches 0dB gain.
Noise Performance
Both parts exhibit excellent voltage noise
performance of ~1 nV/√Hz at high gains. With
~2 pA/√Hz current noise, they are optimized for
relatively low source impedance applications, such as
dynamic microphones with typically a few hundred
ohm output impedances. But, because they have
different internal gain structures, the 1510 has
higher equivalent input noise at 0dB gain
(~57 nV/√Hz) than the 1512, which runs 4.5 dB
lower at ~34 nV/√Hz. The unusual and superior
topology of the THAT 1512 makes its noise performance comparable to some of the better discrete
designs currently available.
Overall gain accuracy depends on the tolerance
of RG and the accuracy of the internal thin-film resistors connected to pins RG1 and RG2 in the 1510/1512
(RA & RB in Figure 1). These internal resistors have a
typical initial accuracy (at room temperature) of
±0.5%, and are typically stable with temperature to
within ±100 ppm/°C. Gain will drift with temperature based on the mismatch between the temperature
coefficient of the external RG and that of the internal
resistors RA & RB.
Inputs
For variable-gain applications where gain
accuracy is important, THAT recommends using
discrete, switched resistors for RG. Where continuous
control is required, or where gain accuracy is less
Simple Configurations
As shown in Figure 2, the 1510/1512 includes
protection diodes at all pins except V+ and V-.
Input Stage
Output Stage
V+
5k
(10k)
-AV
5k
+
-AV
5k
(10k)
+In
5k
-In
RA
5k
RG1
RG2
Out
RB
5k
VFigure 2. THAT 1510 / 1512 Equivalent Circuit with Protection Diodes
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation
Ref
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier
Page 5 of 8
Document 600031 Rev 08
+15
C6
-In
C1
470p
100n
-In
RG1 V+
R1
1k
Out
RG
+In
Ref
C2
470p
C3
47p
Out
RG2 V+In
U1
THAT
1510/1512
C9
R2
1k
100n
-15
Figure 3. Basic 1510 / 1512 Circuit
These diodes reduce the likelihood that accidental
electrostatic discharge (ESD) or electrical over stress
(EOS) will damage the ICs. Other diodes across the
base-emitter junctions of the input transistors
prevent excessive reverse biasing of these junctions
(which would degrade the noise performance of the
input devices).
resistors) to allow gain adjustment, RG should be
ac-coupled as shown in Figure 4. By adding CG in
series with RG, dc gain is fixed (at unity for the 1510,
and ½ for the 1512). This constrains the output dc
offset to just over +/-5 mV, and prevents it from
varying with gain. With this low offset, ac coupling of
the output is usually unnecessary.
Other than the protection diodes, the 1510/1512
input pins are connected only to the bases of their
respective input devices. For proper operation, the
bases must be provided a source of dc bias that will
maintain the inputs within the IC's input commonmode range. Figure 3 shows the simplest approach;
dc bias is supplied via R1 and R2. At 1 kΩ each, they
will minimize pickup of unwanted noise and interference, as well as generate relatively little noise due to
input current noise in the 1510/1512. However, at
high gains, their inherent voltage noise, plus the
1510/1512's input current noise drawn across these
resistors, adds significantly to the noise at the
1510/1512's output.
CG must be large enough not to interfere with
low-frequency response at the smallest values of RG.
For 60 dB gain, RG=10 Ω (1510) or RG=5 Ω (1512).
For a -3 dB point of approximately 5 Hz,
CG=3,300 μF (1510), or CG=6,800 μF (1512). For
other maximum gains or minimum frequencies, scale
CG accordingly.
Because RG is dc coupled in the circuit of
Figure 3, the dc level at the output of the 1510/1512
will vary with gain. In most applications, the output
should be ac-coupled to the next stage. For applications where RG is variable (via a pot or switched
Phantom Power
Phantom power is required for many condenser
microphones. THAT recommends the circuit of
Figure 5 when phantom power is included4. R3, R4,
and D1 - D6 are used to limit the current that flows
through the 1510/1512 inputs when the circuit
inputs (-In and +In) are shorted to ground while
phantom power is turned on. This causes C4 and/or
C5 to discharge through other circuit components,
often generating transient currents of several amps.
R3 and R4 should be at least 10 Ω to limit destructive
4. In revisions 0 and 1 of this data sheet, we recommended using Schottky diodes (1N5819 types) at D 1 ~ D4 to protect the 1510/1512 inputs against overloads. Subse quently, we discovered that the leakage of these diodes could cause problems with DC fluctuations (hence noise) at the 1510/1512 output. Upon further investigation, we
concluded that conventional rectifier diodes like the 1N4004 (the glass-passivated GP version) provide adequate protection and d o not introduce unacceptable leakage.
Additionally, 1N4004 diodes are much cheaper and more readily available than the Schottky types.
Since publishing revision 4, we determined that the internal reverse-bias diodes between the pins +In/RG2 and -In/RG1 may be damaged by phantom power faults under
certain conditions. Small-signal diodes (D 5 and D6) avoid this problem by appearing in parallel with the internal diodes, diverting excess current around the 1510/1512.
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation
Document 600031 Rev 08
Page 6 of 8
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier IC
currents. (Higher values further limit current flow,
but introduce additional source impedance and
noise.) D1 through D4 prevent the IC’s inputs from
significantly exceeding the supply rails. D5 and D6
steer currents around the input stage in the
1510/1512, preventing damage.
Thomas, presented at the 110th AES Convention and
“The 48 Volt Phantom Menace Returns”, by Rosalfonso Bortoni and Wayne Kirkwood presented at the
127th AES Convention.
The series combination of C4 and C5 should be
made large to minimize high-pass filtering of the
signal based upon the sum of the values of R1+R2. As
well, keeping their reactance low relative to the external microphone's source impedance will avoid
increasing the effects of low-frequency current noise
in the 1510/1512 input stage.
A higher common-mode input impedance is
desirable (compared with that of Figures 3 and 4)
when input coupling capacitors (C4 and C5) are used
to block phantom power. At low frequencies where
the reactance of C4 and C5 become significant
(compared to the common-mode input impedances),
the two capacitors interact with the common-mode
input impedance (seen looking to the right-side of
both capacitors) to form voltage dividers for
common-mode signals. Differences in the two capacitors' values leads to different voltage dividers, spoiling the low-frequency common-mode rejection of the
stage. Since C4 and C5 are generally large, electrolytic
types, precise matching is difficult and expensive to
achieve. High common-mode input impedance
reduces the matching requirement by decreasing the
frequency at which the capacitive reactance becomes
significant inversely with the common-mode input
impedance.
Impedance and Line Input Configurations
Other manufacturers have recommended, and
many pro audio products include, a zener diode
arrangement connected to the bridge rectifier instead
of the connection to V+ and V- as shown in Figure 5.
THAT does not recommend this approach, because
we find that R3 and R4 must be made much larger
(e.g., ≥ 51 Ω) in order to limit peak currents enough
to protect reasonably sized zener diodes (eg. 1/2 W).
Such large series input resistors will limit the noise
performance of the preamp. The ultimate floor is set
by the impedance of the microphone, but any
additional series resistance further degrades
performance.
The "T-bias" circuit (R1, R2, and R7) shown in
Figure 5 accommodates this objective. In this circuit,
R1 and R2 are connected to a third resistor R7, boosting the low-frequency common mode input
For further insights into this subject, see the
Audio Engineering Society preprints "The 48 Volt
Phantom Menace," by Gary K. Hebert and Frank W.
+15
C6
-In
C1
470p
+In
100n
-In
RG1 V+
R1
1k
CG
C2
470p
C3
47p
Out
RG
Out
Ref
RG2 V+In
U1
THAT
1510/1512
C9
R2
1k
100n
-15
Figure 4. Basic 1510 / 1512 Circuit with Variable Gain
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier
Page 7 of 8
impedance (as "seen looking in" from the coupling
capacitors) to the value of R1 + (2*R7) -- approximately 45 kΩ with the values shown. The increased
common mode impedance from T-bias improves LF
common mode rejection by reducing capacitor
matching requirements by more than a factor of ten
over the simpler circuit wherein R7=0 Ω. The circuit
works well with the values shown.
Note also that the overall common-mode input
impedance of the circuit is dominated by the
phantom-power resistors (R5 and R6). For the circuit
of Figure 5, this is approximately 5.9 kΩ per leg.
The 1510/1512 can be used as a line input
receiver by adding attenuation to the preamplifier
inputs and changing the circuit topology to allow
ON
-In
R6
6k8
C1
470p
+In
C2
470p
switching of input, fixed attenuation, and gain adjustment. The optimum circuit depends on the specific
requirements of the application. For more details
and specific applications advice, please consult
THAT's application notes, or our applications
engineers at the address and telephone below or via
email at [email protected].
Reference Terminal
The "Ref" pin provides a reference for the output
signal, and is normally connected to analog ground.
If necessary, the "Ref" pin can be used for offset
correction or DC level shifting. However, in order to
prevent spoiling the excellent common-mode rejection of the 1510/1512, the source impedance driving
the
“Ref”
pin
should
be
under
1Ω.
+48V
+15
+15
C4
22u
R5
6k8
C5
22u
C3
47p
Document 600031 Rev 08
D5
C6
1N4148
R3
10
D1
1N4004GP
D3
1N4004GP
D4
1N4004GP
R4
D2
1N4004GP
R1
1k2
R2
1k2
100n
-In
RG1
V+
RG
D6
CG
RG2
1N4148
Ref
U1
THAT
1510/1512
V-
+In
10
-15
Out
Out
C9
R7
22k
100n
-15
Figure 5. Recommended 1510 / 1512 Circuit with Phantom Power
Package Information
Both the THAT 1510 and 1512 are available in
8-pin SOIC, 8-pin DIP, and 14-pin SOIC packages.
The 1510 is also available in a 16-pin (widebody)
SOIC package. Other version/package combinations
will be considered based on customer demand.
The package dimensions are shown in Figures
6, 7, 8, & 9, while pinouts are given in Table 1.
All versions of the 1510 and 1512 are lead free
and RoHS compliant. Material Declaration Data
Sheets on the parts are available at our web site,
www.thatcorp.com or upon request.
THAT Corporation; 45 Sumner Street; Milford, MA 01757-1656; USA
Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
Copyright © 2013, THAT Corporation
Document 600031 Rev 08
Page 8 of 8
C
B
THAT 1510/1512 Low-Noise
High Performance Audio Preamplifier IC
J
1
G
A
K
F
H
D
E
ITEM
A
B
C
D
E
F
G
H
J
K
MILLIMETERS
9.52±0.10
6.35±0.10
7.49/8.13
0.46
2.54
3.68/4.32
0.25
3.18±0.10
8.13/9.40
3.30±0.10
INCHES
0.375±0.004
0.250±0.004
0.295/0.320
0.018
0.100
0.145/0.170
0.010
0.125±0.004
0.320/0.370
0.130±0.004
Figure 6. 8-pin DIP package outline
Figure 7. 16-pin SO Wide package outline
F
E
B
E
F
B C
C
H
H
1
D
D
G
A
A
ITEM
A
B
C
D
E
F
G
H
G
MILLIMETERS
4.80/4.98
3.81/3.99
5.80/6.20
0.36/0.46
1.27
1.35/1.73
0.19/0.25
0.41/1.27
INCHES
0.189/0.196
0.150/0.157
0.228/0.244
0.014/0.018
0.050
0.053/0.068
0.0075/0.0098
0.016/0.05
ITEM
A
B
C
D
E
F
G
H
Figure 8. 8-pin SOIC package outline
MILLIMETERS
8.56/8.79
3.81/3.99
5.80/6.20
0.36/0.46
1.27
1.35/1.73
0.19/0.25
0.41/1.27
INCHES
0.337/0.346
0.150/0.157
0.228/0.244
0.014/0.018
0.050
0.053/0.068
0.0075/0.0098
0.016/0.05
Figure 9. 14-pin SOIC package outline
Revision History
Revision
ECO
Date
Changes
07
2322
9/16/09
Added Max. Input Voltage specification.
2
08
2829
10/02/13
Corrected typographical error in specification table.
3
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Tel: +1 508 478 9200; Fax: +1 508 478 0990; Web: www.thatcorp.com
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