EL2245CS [INTERSIL]
Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp; 双/四通道,低功耗的100MHz增益- 2稳定运算放大器型号: | EL2245CS |
厂家: | Intersil |
描述: | Dual/Quad Low-Power 100MHz Gain-of-2 Stable Op Amp |
文件: | 总12页 (文件大小:246K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
EL2245, EL2445
®
Data Sheet
March 27, 2002
FN7060
Dual/Quad Low-Power 100MHz Gain-of-2
Stable Op Amp
Features
• 100MHz gain-bandwidth
• Gain-of-2 stable
The EL2245 and EL2445 are dual and
quad versions of the popular EL2045.
• Low supply current (per amplifier) - 5.2mA at V = ±15V
S
They are high speed, low power, low
cost monolithic operational amplifiers built on Elantec's
proprietary complementary bipolar process. The EL2245
and EL2445 are gain-of-2 stable and feature a 275V/µs slew
rate and 100MHz bandwidth at gain-of-2 while requiring only
5.2mA of supply current per amplifier.
• Wide supply range - 2.5V to 36V
• High slew rate - 275V/µs
• Fast-settling - 80ns to 0.1% for a 10V step
• Low differential gain - 0.02% at A = +2, R = 150Ω
V
L
The power supply operating range of the EL2245 and
EL2445 is from ±18V down to as little as ±2V. For single-
supply operation, the EL2245 and EL2445 operate from 36V
down to as little as 2.5V. The excellent power supply
operating range of the EL2245 and EL2445 makes them an
obvious choice for applications on a single +5V or +3V
supply.
• Low differential phase - 0.07° at A = +2, R = 150Ω
V
L
• Wide output voltage swing - ±13.6V with V = ±15V,
S
R = 1kΩ
L
Applications
• Video amplifiers
The EL2245 and EL2445 also feature an extremely wide
• Single-supply amplifiers
• Active filters/integrators
• High speed signal processing
• ADC/DAC buffers
output voltage swing of ±13.6V with V = ±15V and
S
R = 1kΩ. At ±5V, output voltage swing is a wide ±3.8V with
L
R = 500Ω and ±3.2V with R = 150Ω. Furthermore, for
L
L
single-supply operation at +5V, output voltage swing is an
excellent 0.3V to 3.8V with R = 500Ω.
L
• Pulse/RF amplifiers
• Pin diode receivers
• Log amplifiers
At a gain of +2, the EL2245 and EL2445 have a -3dB
bandwidth of 100MHz with a phase margin of 50°. Because
of their conventional voltage-feedback topology, the EL2245
and EL2445 allow the use of reactive or non-linear elements
in their feedback network. This versatility combined with low
cost and 75mA of output-current drive make the EL2245 and
EL2445 an ideal choice for price-sensitive applications
requiring low power and high speed.
Ordering Information
TAPE &
REEL
PART NUMBER
EL2245CN
PACKAGE
8-Pin PDIP
PKG. NO.
MDP0031
MDP0027
MDP0027
MDP0027
MDP0031
MDP0027
MDP0027
MDP0027
-
-
EL2245CS
8-Pin SO
EL2245CS-T7
EL2245CS-T13
EL2445CN
8-Pin SO
7”
13”
-
8-Pin SO
14-Pin PDIP
EL2445CS
14-Pin SO (0.150")
14-Pin SO (0.150")
14-Pin SO (0.150")
-
EL2445CS-T7
EL2445CS-T13
7”
13”
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1
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Copyright © Intersil Americas Inc. 2003. All Rights Reserved. Elantec is a registered trademark of Elantec Semiconductor, Inc.
All other trademarks mentioned are the property of their respective owners.
EL2245, EL2445
Pinouts
EL2245
(8-PIN SO, PDIP)
TOP VIEW
EL2445
[14-PIN SO (0.150”), PDIP]
TOP VIEW
OUT1
IN1-
OUT4
IN4-
IN4+
V-
1
2
3
4
5
6
7
14
13
12
11
10
9
OUT
IN1-
IN1+
V-
V+
1
8
7
6
5
-
+
+ -
OUT2
IN2-
IN2+
2
3
4
-
+
IN1+
V+
-
+
IN2+
IN2-
IN3+
IN3-
OUT3
-
+
+ -
OUT2
8
2
EL2245, EL2445
Absolute Maximum Ratings (T = 25°C)
A
Supply Voltage (V ). . . . . . . . . . . . . . . . . . . . . . . . . . . .±18V or 36V
Power Dissipation (P ) . . . . . . . . . . . . . . . . . . . . . . . . . See Curves
D
S
Input Voltage (V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±V
Operating Temperature Range (T ). . . . . . . . . . . . . .-40°C to +85°C
IN)
S
A
Differential Input Voltage (dV ). . . . . . . . . . . . . . . . . . . . . . . . .±10V
Operating Junction Temperature (T ) . . . . . . . . . . . . . . . . . . +150°C
J
IN
Continuous Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . 40mA
Storage Temperature (T ) . . . . . . . . . . . . . . . . . . .-65°C to +150°C
ST
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests
are at the specified temperature and are pulsed tests, therefore: T = T = T
A
J
C
DC Electrical Specifications
V = ±15V, R = 1kΩ, unless otherwise specified.
S L
PARAMETER
DESCRIPTION
Input Offset Voltage
CONDITION
TEMP
MIN
TYP
MAX
4.0
UNIT
mV
mV
µV/°C
µA
µA
µA
nA
nA
nA
nA/°C
V/V
V/V
V/V
V/V
dB
dB
dB
dB
V
V
V
= ±15V
25°C
0.5
OS
S
T
T
T
, T
6.0
MIN MAX
TCV
Average Offset Voltage Drift
Input Bias Current
(Note 1)
All
10.0
2.8
OS
I
V
= ±15V
25°C
8.2
9.2
B
S
, T
MIN MAX
V
V
= ±5V
25°C
25°C
2.8
50
S
I
Input Offset Current
= ±15V
300
400
OS
S
, T
MIN MAX
V
= ±5V
25°C
All
50
0.3
S
TCI
Average Offset Current Drift
Open-loop Gain
(Note 1)
OS
A
V
= ±15V,V
= ±10V, R = 1kΩ
25°C
1500
1500
3000
VOL
S
OUT
L
T
, T
MIN MAX
V
V
V
= ±5V, V
= ±5V, V
= ±2.5V, R = 500Ω
25°C
25°C
25°C
2500
1750
80
S
S
S
OUT
OUT
L
= ±2.5V, R = 150Ω
L
PSRR
CMRR
CMIR
Power Supply Rejection Ratio
Common-mode Rejection Ratio
Common-mode Input Range
= ±5V to ±15V
65
60
70
70
T
T
, T
MIN MAX
V
= ±12V, V
= 0V
OUT
25°C
90
CM
, T
MIN MAX
V
V
V
V
= ±15V
= ±5V
= +5V
25°C
25°C
25°C
25°C
±14.0
±4.2
S
S
S
S
V
4.2/0.1
±13.6
V
V
Output Voltage Swing
= ±15V, R = 1kΩ
±13.4
±13.1
±12.0
±3.4
V
OUT
L
T
, T
V
MIN MAX
V
V
V
V
= ±15V, R = 500Ω
25°C
25°C
25°C
25°C
±13.4
±3.8
±3.2
V
S
S
S
S
L
= ±5V, R = 500Ω
V
L
= ±5V, R = 150Ω
V
L
= +5V, R = 500Ω
3.6/0.4 3.8/0.3
3.5/0.5
V
L
T
T
, T
V
MIN MAX
I
Output Short Circuit Current
25°C
40
35
75
mA
mA
SC
, T
MIN MAX
3
EL2245, EL2445
DC Electrical Specifications
V
= ±15V, R = 1kΩ, unless otherwise specified. (Continued)
S
L
PARAMETER
DESCRIPTION
CONDITION
= ±15V, no load
TEMP
MIN
TYP
MAX
7
UNIT
mA
mA
mA
mA
kΩ
MΩ
pF
I
Supply Current (per amplifier)
V
25°C
5.2
S
S
S
T
7.6
7.6
MIN
T
MAX
V
= ±5V, no load
25°C
25°C
25°C
25°C
25°C
25°C
25°C
5.0
150
15
R
Input Resistance
Differential
IN
Common-mode
C
R
Input Capacitance
Output Resistance
A
A
= +1 @10MHz
= +1
1.0
50
IN
V
mΩ
V
OUT
V
PSOR
Power-supply Operating Range Dual-supply
Single-supply
±2.0
2.5
±18.0
36.0
V
NOTE:
1. Measured from T
to T .
MAX
MIN
Closed-Loop AC Electrical Specifications
V
= ±15V, A = +2, R = 1kΩ unless otherwise specified.
S
V
L
PARAMETER
BW
DESCRIPTION
-3dB Bandwidth
(V = 0.4V
CONDITION
TEMP
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
25°C
MIN
TYP
MAX
UNIT
MHz
MHz
MHz
MHz
MHz
MHz
MHz
MHz
°
V
V
V
V
V
V
V
V
= ±15V, A = +2
100
75
S
S
S
S
S
S
S
S
V
)
PP
OUT
= ±15V, A = -1
V
= ±15V, A = +5
20
V
= ±15V, A = +10
10
V
= ±15V, A = +20
5
V
= ±5V, A = +2
V
75
GBWP
Gain-bandwidth Product
= ±15V
= ±5V
200
150
50
PM
CS
SR
Phase Margin
R = 1 kΩ, C = 10pF
L L
Channel Separation
Slew Rate (Note 1)
f = 5MHz
85
dB
V
V
V
V
= ±15V, R = 1kΩ
200
3.2
275
200
4.4
12.7
3.0
20
V/µs
V/µs
MHz
MHz
ns
S
S
S
S
L
= ±5V, R = 500Ω
L
FPBW
Full-power Bandwidth (Note 2)
= ±15V
= ±5V
t , t
R
Rise Time, Fall Time
Overshoot
0.1V step
0.1V step
F
OS
%
t
t
Propagation Delay
2.5
80
ns
PD
S
Settling to +0.1% (A = +1)
V
V
V
= ±15V, 10V step
= ±5V, 5V step
ns
S
S
60
ns
dG
dP
eN
iN
Differential Gain (Note 3)
Differential Phase (Note 3)
Input Noise Voltage
NTSC/PAL
NTSC/PAL
10kHz
0.02
0.07
15.0
1.50
%
°
nV/√Hz
pA/√Hz
Input Noise Current
10kHz
NOTES:
1. Slew rate is measured on rising edge.
2. For V = ±15V, V
S
= 20V . For V = ±5V, V = 5V . Full-power bandwidth is based on slew rate measurement using: FPBW = SR/(2π
PP OUT PP
OUT
S
* Vpeak).
3. Video performance measured at V = ±15V, A = +2 with 2 times normal video level across R = 150Ω. This corresponds to standard video
S
V
L
levels across a back-terminated 75Ω load. For other values of R , see curves.
L
4
EL2245, EL2445
Test Circuit
Typical Performance Curves
Non-Inverting
Frequency Response
Inverting Frequency
Response
Frequency Response for
Various Load Resistances
Open-Loop Gain and
Phase vs Frequency
Output Voltage Swing
vs Frequency
Equivalent Input Noise
CMRR, PSRR and Closed-
Loop Output Resistance
vs Frequency
2nd and 3rd Harmonic
Distortion vs Frequency
Settling Time vs
Output Voltage Change
Common-Mode Input
Range vs Supply Voltage
Supply Current vs
Supply Voltage
Output Voltage Range
vs Supply Voltage
5
EL2245, EL2445
Typical Performance Curves (Continued)
Gain-Bandwidth Product
vs Supply Voltage
Open-Loop Gain
vs Supply Voltage
Slew-Rate vs
Supply Voltage
Bias and Offset Current
Open-Loop Gain
Voltage Swing
vs Input Common-Mode Voltage
vs Load Resistance
vs Load Resistance
Offset Voltage
vs Temperature
Bias and Output
Current vs Temperature
Supply Current
vs Temperature
Gain-Bandwidth Product
vs Temperature
Open-Loop Gain PSRR
and CMRR vs Temperature
Slew Rate vs
Temperature
6
EL2245, EL2445
Typical Performance Curves (Continued)
Short-Circuit Current
vs Temperature
Small-Signal
Step Response
Large-Signal
Step Response
Differential Gain and
Phase vs DC Input
Offset at 3.58MHz
Differential Gain and
Phase vs DC Input
Offset at 4.43MHz
Differential Gain and
Phase vs Number of
150Ω Loads at 3.58MHz
Differential Gain and
Phase vs Number of
150Ω Loads at 4.43MHz
Channel Separation
vs Frequency
7
EL2245, EL2445
Typical Performance Curves (Continued)
Gain-Bandwidth Product vs Load Capacitance
100
Overshoot vs Load Capacitance
40
35
30
25
20
15
10
5
80
60
40
20
V
=±15V
V =±15V
S
S
A =-2
R =1kΩ
V
G
0
0
1
10
100
1k
10k
50
250
450
650
850
1050
Load Capacitance (pF)
Load Capacitance (pF)
Package Power Dissipation vs Ambient Temperature
JEDEC JESD51-3 Low Effective Thermal Conductivity
(Single Layer) Test Board
Package Power Dissipation vs Ambient Temperature
JEDEC JESD51-3 Low Effective Thermal Conductivity
(Single Layer) Test Board
1.8
1.6
1.4
1.2
1
1.2
1
1.54W
1.042W
PDIP14
SO14
=120°C/W
0.8
0.6
0.4
0.2
0
1.25W
θ
=81°C/W
θ
JA
JA
781mW
PDIP8
=100°C/W
0.8
0.6
0.4
0.2
0
θ
JA
SO8
=160°C/W
θ
JA
0
25
50
75 85 100
125
150
0
25
50
75 85 100
125
150
Ambient Temperature (°C)
Ambient Temperature (°C)
Simplified Schematic (Per Amplifier)
8
EL2245, EL2445
where:
Burn-In Circuit (Per Amplifier)
T
= Maximum ambient temperature
MAX
θ
= Thermal resistance of the package
JA
PD
= Maximum power dissipation of each amplifier
MAX
V = Supply voltage
S
I
= Maximum supply current of each amplifier
SMAX
V
= Maximum output voltage swing of the
OUTMAX
application
ALL PACKAGES USE THE SAME SCHEMATIC
R = Load resistance
L
Applications Information
To serve as a guide for the user, we can calculate maximum
allowable supply voltages for the example of the video cable-
Product Description
The EL2245 and EL2445 are dual and quad low-power
wideband monolithic operational amplifiers built on Elantec's
proprietary high-speed complementary bipolar process. The
EL2245 and EL2445 use a classical voltage-feedback
topology which allows them to be used in a variety of
applications where current-feedback amplifiers are not
appropriate because of restrictions placed upon the
feedback element used with the amplifier. The conventional
topology of the EL2245 and EL2445 allows, for example, a
capacitor to be placed in the feedback path, making it an
excellent choice for applications such as active filters,
sample-and-holds, or integrators. Similarly, because of the
ability to use diodes in the feedback network, the EL2245
and EL2445 are an excellent choice for applications such as
fast log amplifiers.
driver below since we know that T
JMAX
= 150°C, T
=
MAX
= 7.6mA per amplifier, and the package θ
85°C, I
s
SMAX
JA
are shown in Table 1. If we assume (for this example) that we
are driving a back-terminated video cable, then the
maximum average value (over duty-cycle) of V
OUTMAX
is
1.4V, and R = 150Ω, giving the results seen in Table 1.
L
TABLE 1.
MAX PDISS
PART
DUALS
PACKAGE
Θ
@T
MAX V
S
JA
MAX
EL2245CN
EL2245CS
QUADS
PDIP8
SO8
100°C/W 0.650W @85°C ±16.6V
160°C/W 0.406W @85°C ±10.5V
EL2445CN
EL2445CS
PDIP14
SO14
81°C/W 0.802W @85°C ±11.5V
120°C/W 0.542W @85°C ±7.5V
Power Dissipation
With the wide power supply range and large output drive
capability of the EL2245 and EL2445, it is possible to exceed
the 150°C maximum junction temperatures under certain
load and power-supply conditions. It is therefore important to
Single-Supply Operation
The EL2245 and EL2445 have been designed to have a
wide input and output voltage range. This design also makes
the EL2245 and EL2445 an excellent choice for single-
supply operation. Using a single positive supply, the lower
calculate the maximum junction temperature (T
) for all
JMAX
applications to determine if power supply voltages, load
conditions, or package type need to be modified for the
EL2245 and EL2445 to remain in the safe operating area.
These parameters are related as follows:
input voltage range is within 100mV of ground (R = 500Ω),
L
and the lower output voltage range is within 300mV of
ground. Upper input voltage range reaches 4.2V, and output
voltage range reaches 3.8V with a 5V supply and
T
= T
+ (Θ × PD
)
MAXTOTAL
JMAX
MAX
JA
R = 500Ω. This results in a 3.5V output swing on a single
L
where:
5V supply. This wide output voltage range also allows single-
supply operation with a supply voltage as high as 36V or as
low as 2.5V. On a single 2.5V supply, the EL2245 and
EL2445 still have 1V of output swing.
PD
is the sum of the maximum power dissipation
MAXTOTAL
of each amplifier in the package (PD
). PDmax for each
MAX
amplifier can be calculated as follows:
V
OUTMAX
Gain-Bandwidth Product and the -3dB Bandwidth
----------------------------
PD
= 2 × V × I
+ (V – V
) ×
MAX
S
SMAX
S
OUTMAX
R
L
The EL2245 and EL2445 have a bandwidth at gain-of-2 of
100MHz while using only 5.2mA of supply current per
amplifier. For gains greater than 4, their closed-loop -3dB
bandwidth is approximately equal to the gain-bandwidth
product divided by the noise gain of the circuit. For gains
less than 4, higher-order poles in the amplifiers' transfer
9
EL2245, EL2445
function contribute to even higher closed loop bandwidths.
techniques will help assure rapid, high quality results. As
with any high-frequency device, good PCB layout is
necessary for optimum performance. Ground-plane
construction is highly recommended, as is good power
supply bypassing. A 0.1µF ceramic capacitor is
recommended for bypassing both supplies. Lead lengths
should be as short as possible, and bypass capacitors
should be as close to the device pins as possible. For good
AC performance, parasitic capacitances should be kept to a
minimum at both inputs and at the output. Resistor values
should be kept under 5kΩ because of the RC time constants
associated with the parasitic capacitance. Metal-film and
carbon resistors are both acceptable, use of wire-wound
resistors is not recommended because of their parasitic
inductance. Similarly, capacitors should be low-inductance
for best performance.
For example, the EL2245 and EL2445 have a -3dB
bandwidth of 100MHz at a gain of +2, dropping to 20MHz at
a gain of +5. It is important to note that the EL2245 and
EL2445 have been designed so that this “extra” bandwidth in
low-gain applications does not come at the expense of
stability. As seen in the typical performance curves, the
EL2245 and EL2445 in a gain of +2 only exhibit 1.0dB of
peaking with a 1kΩ load.
Video Performance
An industry-standard method of measuring the video
distortion of components such as the EL2245/ EL2445 is to
measure the amount of differential gain (dG) and differential
phase (dP) that they introduce. To make these
measurements, a 0.286V (40 IRE) signal is applied to the
PP
device with 0V DC offset (0 IRE) at either 3.58MHz for NTSC
or 4.43MHz for PAL. A second measurement is then made at
0.714V DC offset (100 IRE). Differential gain is a measure of
the change in amplitude of the sine wave, and is measured
in percent. Differential phase is a measure of the change in
phase, and is measured in degrees.
The EL2245 and EL2445 Macromodel
This macromodel has been developed to assist the user in
simulating the EL2245 and EL2445 with surrounding
circuitry. It has been developed for the PSPICE simulator
(copywritten by the Microsim Corporation), and may need to
be rearranged for other simulators. It approximates DC, AC,
and transient response for resistive loads, but does not
accurately model capacitive loading. This model is slightly
more complicated than the models used for low-frequency
op-amps, but it is much more accurate for AC analysis.
For signal transmission and distribution, a back-terminated
cable (75Ω in series at the drive end, and 75Ω to ground at
the receiving end) is preferred since the impedance match at
both ends will absorb any reflections. However, when double
termination is used, the received signal is halved; therefore a
gain of 2 configuration is typically used to compensate for
the attenuation.
The model does not simulate these characteristics
accurately:
The EL2245 and EL2445 have been designed as an
economical solution for applications requiring low video
distortion. They have been thoroughly characterized for
video performance in the topology described above, and the
results have been included as typical dG and dP
specifications and as typical performance curves. In a gain
of +2, driving 150Ω, with standard video test levels at the
input, the EL2245 and EL2445 exhibit dG and dP of only
0.02% and 0.07° at NTSC and PAL. Because dG and dP can
vary with different DC offsets, the video performance of the
EL2245 and EL2445 has been characterized over the entire
DC offset range from -0.714V to +0.714V. For more
information, refer to the curves of dG and dP vs DC Input
Offset.
• Noise
• Settling time
• Non-linearities
• Temperature effects
• Manufacturing variations
• CMRR
• PSRR
Output Drive Capability
The EL2245 and EL2445 have been designed to drive low
impedance loads. They can easily drive 6V into a 150Ω
PP
load. This high output drive capability makes the EL2245
and EL2445 an ideal choice for RF, IF and video
applications. Furthermore, the current drive of the EL2245
and EL2445 remains a minimum of 35mA at low
temperatures.
Printed-Circuit Layout
The EL2245 and EL2445 are well behaved, and easy to
apply in most applications. However, a few simple
10
EL2245, EL2445
EL2245 and EL2445 Macromodel
* Connections: +input
*
*
*
*
*
|
|
|
|
|
-input
|
|
|
+Vsupply
|
|
-Vsupply
|
|
output
|
|
|
.subckt M2245 3
*
2
7
4
6
* Input stage
*
ie 7 37 1mA
r6 36 37 400
r7 38 37 400
rc1 4 30 850
rc2 4 39 850
q1 30 3 36 qp
q2 39 2 38 qpa
ediff 33 0 39 30 1.0
rdiff 33 0 1Meg
*
* Compensation Section
*
ga 0 34 33 0 1m
rh 34 0 2Meg
ch 34 0 1.3pF
rc 34 40 1K
cc 40 0 1pF
*
* Poles
*
ep 41 0 40 0 1
rpa 41 42 200
cpa 42 0 1pF
rpb 42 43 200
cpb 43 0 1pF
*
* Output Stage
*
ios1 7 50 1.0mA
ios2 51 4 1.0mA
q3 4 43 50 qp
q4 7 43 51 qn
q5 7 50 52 qn
q6 4 51 53 qp
ros1 52 6 25
ros2 6 53 25
*
* Power Supply Current
*
ips 7 4 2.7mA
*
* Models
*
.model qn npn(is=800E-18 bf=200 tf=0.2nS)
.model qpa pnp(is=864E-18 bf=100 tf=0.2nS)
.model qp pnp(is=800E-18 bf=125 tf=0.2nS)
.ends
11
EL2245, EL2445
EL2245 and EL2445 Macromodel (Continued)
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Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
12
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