DRV135 [BB]
AUDIO BALANCED LINE DRIVERS; 音频平衡线路驱动器型号: | DRV135 |
厂家: | BURR-BROWN CORPORATION |
描述: | AUDIO BALANCED LINE DRIVERS |
文件: | 总10页 (文件大小:231K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
®
DRV134
DRV134
DRV135
DRV134
DRV135
AUDIO BALANCED LINE DRIVERS
DESCRIPTION
FEATURES
The DRV134 and DRV135 are differential output
amplifiers that convert a single-ended input to a
balanced output pair. These balanced audio drivers
consist of high performance op amps with on-chip
precision resistors. They are fully specified for high
performance audio applications and have excellent
ac specifications, including low distortion (0.0005%
at 1kHz) and high slew rate (15V/µs).
● BALANCED OUTPUT
● LOW DISTORTION: 0.0005% at f = 1kHz
● WIDE OUTPUT SWING: 17Vrms into 600Ω
● HIGH CAPACITIVE LOAD DRIVE
● HIGH SLEW RATE: 15V/µs
● WIDE SUPPLY RANGE: ±4.5V to ±18V
● LOW QUIESCENT CURRENT: ±5.2mA
● 8-PIN DIP, SO-8, AND SOL-16 PACKAGES
The on-chip resistors are laser-trimmed for accurate
gain and optimum output common-mode rejection. Wide
output voltage swing and high output drive capability
allow use in a wide variety of demanding applications.
They easily drive the large capacitive loads associated
with long audio cables. Used in combination with the
INA134 or INA137 differential receivers, they offer a
complete solution for transmitting analog audio signals
without degradation.
● COMPANION TO AUDIO DIFFERENTIAL
LINE RECEIVERS: INA134 and INA137
● IMPROVED REPLACEMENT FOR SSM2142
APPLICATIONS
● AUDIO DIFFERENTIAL LINE DRIVER
● AUDIO MIX CONSOLES
The DRV134 is available in 8-pin DIP and SOL-16
surface-mount packages. The DRV135 comes in a
space-saving SO-8 surface-mount package. Both are
specified for operation over the extended industrial
temperature range, –40°C to +85°C and operate from
–55°C to +125°C.
● DISTRIBUTION AMPLIFIER
● GRAPHIC/PARAMETRIC EQUALIZERS
● DYNAMIC RANGE PROCESSORS
● DIGITAL EFFECTS PROCESSORS
● TELECOM SYSTEMS
● HI-FI EQUIPMENT
V+
● INDUSTRIAL INSTRUMENTATION
50Ω
+VO
A2
+Sense
–Sense
10kΩ
VIN
A1
50Ω
Gnd
–VO
A3
10kΩ
All resistors 30kΩ unless otherwise indicated.
V–
International Airport Industrial Park
•
Mailing Address: PO Box 11400, Tucson, AZ 85734
FAXLine: (800) 548-6133 (US/Canada Only)
• Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111
Internet: http://www.burr-brown.com/
•
•
Cable: BBRCORP
•
Telex: 066-6491
•
FAX: (520) 889-1510
•
Immediate Product Info: (800) 548-6132
©1998 Burr-Brown Corporation
PDS-1451A
Printed in U.S.A. October, 1998
SPECIFICATIONS: VS = ±18V
At TA = +25°C, VS = ±18V, RL = 600Ω differential connected between +VO and –VO, unless otherwise noted.
DRV134PA, UA
DRV135UA
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
AUDIO PERFORMANCE
Total Harmonic Distortion + Noise
THD+N
f = 20Hz to 20kHz,VO = 10Vrms
f = 1kHz, VO = 10Vrms
20kHz BW
0.001
0.0005
–98
%
%
Noise Floor, RTO(1)
Headroom, RTO(1)
dBu
dBu
THD+N < 1%
+27
INPUT
Input Impedance(2)
ZIN
IIN
10
kΩ
µA
Input Current
VIN = ±7.07V
±700
±1000
GAIN
[(+VO) – (–VO)]/VIN
Differential
VIN = ±10V
Initial
5.8
5.8
6
dB
%
Error
±0.1
±10
±2
±2
vs Temperature
Single-Ended
Initial
ppm/°C
VIN = ±5V
6
dB
%
Error
±0.7
±10
vs Temperature
Nonlinearity
ppm/°C
% of FS
0.0003
OUTPUT
Common-Mode Rejection, f = 1kHz
Signal Balance Ratio, f = 1kHz
Output Offset Voltage
Offset Voltage, Common-Mode
vs Temperature
OCMR See OCMR Test Circuit, Figure 4
46
35
68
54
dB
dB
SBR
See SBR Test Circuit, Figure 5
(3)
VOCM
VIN = 0
VIN = 0
±50
±150
±1
±250
±10
mV
µV/°C
mV
µV/°C
dB
(4)
Offset Voltage, Differential
vs Temperature
VOD
±5
vs Power Supply
PSRR
VS = ±4.5V to ±18V
No Load(5)
80
110
Output Voltage Swing, Positive
Negative
(V+) – 3
(V–) + 2
(V+) – 2.5
(V–) + 1.5
50
V
No Load(5)
V
Impedance
Ω
Load Capacitance, Stable Operation
Short-Circuit Current
CL
CL Tied to Ground (each output)
1
µF
ISC
±85
mA
FREQUENCY RESPONSE
Small-Signal Bandwidth
Slew Rate
1.5
15
2.5
3
MHz
V/µs
µs
SR
Settling Time: 0.01%
Overload Recovery
VOUT = 10V Step
Output Overdriven 10%
µs
POWER SUPPLY
Rated Voltage
VS
IQ
±18
V
V
Voltage Range
Quiescent Current
±4.5
±18
IO = 0
±5.2
±5.5
mA
TEMPERATURE RANGE
Specification Range
Operation Range
–40
–55
–55
+85
+125
+125
°C
°C
°C
Storage Range
Thermal Resistance
8-Pin DIP
SO-8 Surface Mount
SOL-16 Surface Mount
θJA
100
150
80
°C/W
°C/W
°C/W
NOTES: (1) dBu = 20log (Vrms/0.7746). (2) Resistors are ratio matched but have ±20% absolute value. (3) VOCM = [(+VO) + (–VO)]/2. (4) VOD = (+VO) – (–VO).
(5) Guarantees linear operation. Includes common-mode offset.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.
®
2
DRV134, 135
PIN CONFIGURATIONS
Top View
SOL-16
Top View
8-Pin DIP/SO-8
NC
NC
1
2
3
4
5
6
7
8
16 NC
15 NC
14 +VO
13 +Sense
12 V+
–VO
–Sense
Gnd
1
2
3
4
8
7
6
5
+VO
+Sense
V+
–VO
–Sense
Gnd
VIN
VIN
V–
11 V–
NC
10 NC
NC
9
NC
ABSOLUTE MAXIMUM RATINGS(1)
Supply Voltage, V+ to V–.................................................................... 40V
Input Voltage Range.................................................................... V– to V+
Output Short-Circuit (to ground).............................................. Continuous
Operating Temperature ..................................................–55°C to +125°C
Storage Temperature .....................................................–55°C to +125°C
Junction Temperature .................................................................... +150°C
Lead Temperature (soldering, 10s)............................................... +300°C
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with ap-
propriate precautions. Failure to observe proper handling and
installation procedures can cause damage.
NOTE: (1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods may affect
device reliability.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.
PACKAGE/ORDERING INFORMATION
PACKAGE
DRAWING
NUMBER(1)
SPECIFIED
TEMPERATURE
RANGE
ORDERING
NUMBER(2)
TRANSPORT
MEDIA
PRODUCT
PACKAGE
DRV134PA
DRV134UA
8-Pin DIP
SOL-16 Surface Mount
006
211
"
182
"
–40°C to +85°C
–40°C to +85°C
DRV134PA
DRV134UA
DRV134UA/1K
DRV135UA
Rails
Rails
Tape and Reel
Rails
"
"
"
DRV135UA
"
SO-8 Surface Mount
"
–40°C to +85°C
"
DRV135UA/2K5
Tape and Reel
NOTES: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book. For detailed Tape and Reel
mechanical information refer to Appendix B of Burr-Brown IC Data Book. (2) Models with a slash (/) are available only in Tape and Reel in the quantities indicated
(e.g., /2K5 indicates 2500 devices per reel). Ordering 2500 pieces of “DRV135UA/2K5” will get a single 2500-piece Tape and Reel. For detailed Tape and Reel
mechanical information, refer to Appendix B of Burr-Brown IC Data Book.
®
3
DRV134, 135
TYPICAL PERFORMANCE CURVES
At TA = +25°C, VS = ±18V, RL = 600Ω differential connected between +VO and –VO, unless otherwise noted.
TOTAL HARMONIC DISTORTION+NOISE
vs FREQUENCY
TOTAL HARMONIC DISTORTION+NOISE
vs FREQUENCY
0.01
0.01
Differential Mode
Differential Mode
VO = 10Vrms
500 feet cable
See Figure 3 for Test Circuit
See Figure 3 for Test Circuit
A: R1 = R2 = RL = ∞ (no load)
B: R1 = R2 = 600Ω, RL = ∞
C: R1 = R2 = ∞, RL = 600Ω
VO = 10Vrms
A: R1 = R2 = RL = ∞ (no load)
B: R1 = R2 = 600Ω, RL = ∞
C: R1 = R2 = ∞, RL = 600Ω
No Cable
A
A
B
B
0.001
0.001
C
C
DRV134 Output
100
DRV134 Output
100
0.0001
0.0001
20
1k
Frequency (Hz)
10k 20k
20
20
5
1k
Frequency (Hz)
10k 20k
TOTAL HARMONIC DISTORTION+NOISE
vs FREQUENCY
SYSTEM TOTAL HARMONIC DISTORTION+NOISE
vs FREQUENCY
0.1
0.01
0.01
Single-Ended Mode
VO = 10Vrms
–VO or +VO Grounded
A: R1 = 600Ω (250 ft cable)
B: R1 = ∞ (no cable)
See Figure 3 for Test Circuit
A: R1 = R2 = RL = ∞ (no load)
B: R1 = R2 = ∞ RL = 600Ω
Differential Mode
VO = 10Vrms
A (no cable)
A
0.001
B
0.001
0.0001
B (500ft cable)
INA137 Output
100
DRV134 Output
100
0.0001
20
1k
Frequency (Hz)
10k 20k
1k
10k 20k
Frequency (Hz)
HEADROOM—TOTAL HARMONIC DISTORTION+NOISE
vs OUTPUT AMPLITUDE
DIM INTERMODULATION DISTORTION
vs OUTPUT AMPLITUDE
1
0.1
1
0.1
f = 1kHz
Single-Ended
Mode
Differential
Mode
Differential Mode
500 ft Cable
500 ft Cable
500 ft Cable
RL = 600Ω
R
= 600Ω
R
= 600Ω
L
L
0.01
0.01
0.001
0.0001
0.001
0.0001
No Cable
RL = ∞
No Cable
= ∞
BW = 30kHz
10
DRV134 Output
10
R
L
5
15
20
25
30
15
20
25
30
Output Amplitude (dBu)
Output Amplitude (dBu)
®
4
DRV134, 135
TYPICAL PERFORMANCE CURVES (CONT)
At TA = +25°C, VS = ±18V, RL = 600Ω differential connected between +VO and –VO, unless otherwise noted.
HARMONIC DISTORTION PRODUCTS
vs FREQUENCY
GAIN vs FREQUENCY
0.01
0.001
10
5
Differential Mode
No Cable, RL = ∞
500 ft Cable,
RL = 600Ω
2nd Harmonic
0
0.0001
0.00001
–5
–10
3rd Harmonic
10k 20k
20
100
1k
1k
10k
100k
1M
10M
Frequency (Hz)
Frequency (Hz)
OUTPUT VOLTAGE NOISE SPECTRAL DENSITY
vs FREQUENCY
OUTPUT VOLTAGE NOISE
vs NOISE BANDWIDTH
10k
1k
100
10
1
100
10
0.1
1
10
100
1k
10k
100k
1M
1
10
100
1k
10k
100k
Frequency (Hz)
Frequency (Hz)
MAXIMUM OUTPUT VOLTAGE SWING
vs FREQUENCY
POWER SUPPLY REJECTION vs FREQUENCY
+PSRR
120
100
80
60
40
20
0
20
16
12
10
8
0.1% Distortion
0.01% Distortion
–PSRR
4
RL = 600Ω
Diff Mode
VS = ±4.5V to ±18V
0
10
100
1k
10k
100k
1M
10k
20k
50k
80k 100k
Frequency (Hz)
Frequency (Hz)
®
5
DRV134, 135
TYPICAL PERFORMANCE CURVES (CONT)
At TA = +25°C, VS = ±18V, RL = 600Ω differential connected between +VO and –VO, unless otherwise noted.
OUTPUT VOLTAGE SWING
vs OUTPUT CURRENT
OUTPUT VOLTAGE SWING
vs SUPPLY VOLTAGE
18
16
20
16
12
1
THD+N ≤ 0.1%
+25°C
–55°C
14
12
+125°C
10
8
–8
+25°C
–55°C
–10
–12
–14
–16
–18
+125°C
8
4
0
0
±20
±40
±60
±80
±100
±4
±6
±8
±10
±12
±14
±16
±18
Output Current (mA)
Supply Voltage
QUIESCENT CURRENT
vs SUPPLY VOLTAGE
SHORT-CIRCUIT CURRENT vs TEMPERATURE
±5.6
±5.4
±5.2
±5
±120
±100
±80
±60
±40
±20
+ISC
T = –55°C
T = +25°C
T = +125°C
–ISC
±4.8
±4.6
±4
±6
±8
±10
±12
±14
±16
±18
–75
–50
–25
0
25
50
75
100
125
Supply Voltage (V)
Temperature (°C)
DIFFERENTIAL OFFSET VOLTAGE
PRODUCTION DISTRIBUTION
COMMON-MODE OFFSET VOLTAGE
PRODUCTION DISTRIBUTION
45
40
35
30
25
20
15
10
5
35
30
25
20
15
10
5
Typical production
Typical production
distribution of packaged
units. All package types
included.
distribution of packaged
units. All package types
included.
0
0
Differential Offset Voltage (mV)
Common-Mode Offset Voltage (mV)
®
6
DRV134, 135
TYPICAL PERFORMANCE CURVES (CONT)
At TA = +25°C, VS = ±18V, RL = 600Ω differential connected between +VO and –VO, unless otherwise noted.
SMALL-SIGNAL STEP RESPONSE
CL = 100pF
SMALL-SIGNAL STEP RESPONSE
CL = 1000pF
2µs/div
2µs/div
LARGE-SIGNAL STEP RESPONSE
CL = 100pF
LARGE-SIGNAL STEP RESPONSE
CL = 1000pF
2µs/div
2µs/div
SMALL-SIGNAL OVERSHOOT
vs LOAD CAPACITANCE
40
100mV Step
30
20
10
0
10
100
1k
10k
Load Capacitance (pF)
®
7
DRV134, 135
resistors. Characterized by low differential-mode output
impedance (50Ω) and high common-mode output imped-
ance (1.6kΩ), the DRV134 is ideal for audio applications.
Normally, +VO is connected to +Sense, –VO is connected to
–Sense, and the outputs are taken from these junctions as
shown in Figure 1. For applications with large dc cable
offset errors, a 10µF electrolytic nonpolarized blocking
capacitor at each sense pin is recommended as shown in
Figure 2.
APPLICATIONS INFORMATION
The DRV134 (and DRV135 in SO-8 package) converts a
single-ended, ground-referenced input to a floating differ-
ential output with +6dB gain (G = 2). Figure 1 shows the
basic connections required for operation. Decoupling ca-
pacitors placed close to the device pins are strongly recom-
mended in applications with noisy or high impedance power
supplies.
The DRV134 consists of an input inverter driving a cross-
coupled differential output stage with 50Ω series output
V–
V+
1µF
1µF
5
(11)
6 (12)
DRV134
DRV135
50Ω
8
+VO
A2
(14)
7
(13)
+Sense
G = +6dB
–Sense
10kΩ
4
VIN
(6)
2
(4)
1
A1
50Ω
3
Gnd
–VO
A3
(5)
(3)
10kΩ
All resistors 30kΩ unless otherwise indicated.
SOL-16 pin numbers in parentheses.
FIGURE 1. Basic Connections.
DRIVER
DRV134
DRV135
RECEIVER
50Ω
8
7
A2
–VO
5
6
1
10µF(1)
BALANCED
CABLE PAIR
+VO
2
10kΩ
4
3
VO
VIN
10µF(1)
2
1
3
–VO
A1
50Ω
+VO
Gnd
A3
INA134, INA137
INA134 (G = 1): VO = 2VIN
INA137 (G = 1/2): VO = VIN
10kΩ
All resistors 30kΩ unless otherwise indicated.
Pin numbers shown for DIP and SO-8 versions.
NOTE: (1) Optional 10µF electrolytic (nonpolarized) capacitors reduce common-mode offset errors.
FIGURE 2. Complete Audio Driver/Receiver Circuit.
®
8
DRV134, 135
Excellent internal design and layout techniques provide low
signal distortion, high output level (+27dBu), and a low
noise floor (–98dBu). Laser trimming of thin film resistors
assures excellent output common-mode rejection (OCMR)
and signal balance ratio (SBR). In addition, low dc voltage
offset reduces errors and minimizes load currents.
Up to approximately 10kHz, distortion is below the mea-
surement limit of commonly used test equipment. Further-
more, distortion remains relatively constant over the wide
output voltage swing range (approximately 2.5V from the
positive supply and 1.5V from the negative supply). A
special output stage topology yields a design with minimum
distortion variation from lot-to-lot and unit-to-unit. Further-
more, the small and large signal transient response curves
demonstrate the DRV134’s stability under load.
For best system performance, it is recommended that a high
input-impedance difference amplifier be used as the re-
ceiver. Used with the INA134 (G = 0dB) or the INA137 (G
= ±6dB) differential line receivers, the DRV134 forms a
complete solution for driving and receiving audio signals,
replacing input and output coupling transformers commonly
used in professional audio systems (Figure 2). When used
with the INA137 (G = –6dB) overall system gain is unity.
OUTPUT COMMON-MODE REJECTION
Output common-mode rejection (OCMR) is defined as the
change in differential output voltage due to a change in
output common-mode voltage. When measuring OCMR,
VIN is grounded and a common-mode voltage, VCM, is
applied to the output as shown in Figure 4. Ideally no
differential mode signal (VOD) should appear. However, a
small mode-conversion effect causes an error signal whose
magnitude is quantified by OCMR.
AUDIO PERFORMANCE
The DRV134 was designed for enhanced ac performance.
Very low distortion, low noise, and wide bandwidth provide
superior performance in high quality audio applications.
Laser-trimmed matched resistors provide optimum output
common-mode rejection (typically 68dB), especially when
compared to circuits implemented with op amps and discrete
precision resistors. In addition, high slew rate (15V/µs) and
fast settling time (2.5µs to 0.01%) ensure excellent dynamic
response.
+18V
1µF
300Ω(1)
VIN
+VO
6
The DRV134 has excellent distortion characteristics. As
shown in the distortion data provided in the typical perfor-
mance curves, THD+Noise is below 0.003% throughout the
audio frequency range under various output conditions. Both
differential and single-ended modes of operation are shown.
In addition, the optional 10µF blocking capacitors used to
minimize VOCM errors have virtually no effect on perfor-
mance. Measurements were taken with an Audio Precision
System One (with the internal 80kHz noise filter) using the
THD test circuit shown in Figure 3.
4
3
7
8
VOD
DRV134
300Ω(1)
1
Gnd
2
5
–VO
600Ω
1µF
V
CM = 10Vp-p
–18V
VOD
OCMR = –20 Log
at f = 1kHz, VOD = (+VO) – (–VO)
( V )
CM
NOTE: (1) Matched to 0.1%.
FIGURE 4. Output Common-Mode Rejection Test Circuit.
+18V
+18V
1µF
1µF
Test Point
or
+VO
–In
6
7
VIN
4
3
7
2
8
5
DRV134
INA137
VOUT
RL
6
1
1
2
+In
5
4
–VO
3
R1
R2
1µF
1µF
–18V
–18V
NOTE: Cable loads, where indicated, are Belden 9452 cable.
FIGURE 3. Distortion Test Circuit.
®
9
DRV134, 135
SIGNAL BALANCE RATIO
For best rejection of line noise and hum differential mode
operation is recommended. However, single-ended perfor-
mance is adequate for many applications. In general single-
ended performance is comparable to differential mode (see
THD+N typical performance curves), but the common-
mode and noise rejection inherent in balanced-pair systems
is lost.
Signal balance ratio (SBR) measures the symmetry of the
output signals under loaded conditions. To measure SBR an
input signal is applied and the outputs are summed as shown
in Figure 5. VOUT should be zero since each output ideally
is exactly equal and opposite. However, an error signal
results from any imbalance in the outputs. This error is
quantified by SBR. The impedances of the DRV134’s out
put stages are closely matched by laser trimming to mini-
mize SBR errors. In an application, SBR also depends on the
balance of the load network.
CABLE
The DRV134 is capable of driving large signals into 600Ω
loads over long cables. Low impedance shielded audio
cables such as the standard Belden 8451 or 9452 (or similar)
are recommended, especially in applications where long
cable lengths are required.
+18V
1µF
THERMAL PERFORMANCE
300Ω(1)
V
IN = 10Vp-p
+VO
The DRV134 and DRV135 have robust output drive capa-
bility and excellent performance over temperature. In most
applications there is no significant difference between the
DIP, SOL-16, and SO-8 packages. However, for applica-
tions with extreme temperature and load conditions, the
SOL-16 (DRV134UA) or DIP (DRV134PA) packages are
recommended. Under these conditions, such as loads greater
than 600Ω or very long cables, performance may be de-
graded in the SO-8 (DRV135UA) package.
6
4
3
7
8
DRV134
300Ω(1)
1
Gnd
2
VOUT
600Ω
5
–VO
1µF
–18V
VOUT
SBR = –20 Log
at f = 1kHz
( V )
IN
LAYOUT CONSIDERATIONS
NOTE: (1) Matched to 0.1%.
A driver/receiver balanced-pair (such as the DRV134 and
INA137) rejects the voltage differences between the grounds
at each end of the cable, which can be caused by ground
currents, supply variations, etc. In addition to proper bypass-
ing, the suggestions below should be followed to achieve
optimal OCMR and noise rejection.
FIGURE 5. Signal Balance Ratio Test Circuit.
SINGLE-ENDED OPERATION
The DRV134 can be operated in single-ended mode without
degrading output drive capability. Single-ended operation
requires that the unused side of the output pair be grounded
(both the VO and Sense pins) to a low impedance return path.
Gain remains +6dB. Grounding the negative outputs as
shown in Figure 6 results in a noninverted output signal
(G = +2) while grounding the positive outputs gives an
inverted output signal (G = –2).
• The DRV134 input should be driven by a low impedance
source such as an op amp or buffer.
• As is the case for any single-ended system, the source’s
common should be connected as close as possible to the
DRV134’s ground. Any ground offset errors in the source
will degrade system performance.
• Symmetry on the outputs should be maintained.
V+
• Shielded twisted-pair cable is recommended for all appli-
cations. Physical balance in signal wiring should be main-
tained. Capacitive differences due to varying wire lengths
may result in unequal noise pickup between the pair and
degrade OCMR. Follow industry practices for proper sys-
tem grounding of the cables.
VOUT = 2VIN
6
VIN
7
4
3
8
1
600Ω
DRV134
2
5
G = +6dB
V–
FIGURE 6. Typical Single-Ended Application.
®
10
DRV134, 135
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