ADR430BRZ-REEL7 [ADI]
Ultralow Noise XFET Voltage References with Current Sink and Source Capability; 超低噪声XFET基准电压与电流库和源能力型号: | ADR430BRZ-REEL7 |
厂家: | ADI |
描述: | Ultralow Noise XFET Voltage References with Current Sink and Source Capability |
文件: | 总24页 (文件大小:1182K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
Ultralow Noise XFET® Voltage References
with Current Sink and Source Capability
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
PIN CONFIGURATIONS
FEATURES
Low noise (0.1 Hz to 10 Hz): 3.5 µV p-p @ 2.5 V output
No external capacitor required
Low temperature coefficient
A Grade: 10 ppm/°C max
TP
1
2
3
4
8
7
6
5
TP
ADR43x
TOP VIEW
(Not to Scale)
V
IN
NC
NC
V
OUT
GND
TRIM
B Grade: 3 ppm/°C max
NC = NO CONNECT
Load regulation: 15 ppm/mA
Line regulation: 20 ppm/V
Wide operating range
Figure 1. 8-Lead MSOP
(RM Suffix)
ADR430: 4.1 V to 18 V
ADR431: 4.5 V to 18 V
ADR433: 5.0 V to 18 V
ADR434: 6.1 V to 18 V
ADR435: 7.0 V to 18 V
TP
1
2
3
4
8
7
6
5
TP
NC
V
ADR43x
TOP VIEW
(Not to Scale)
V
IN
NC
OUT
GND
TRIM
ADR439: 6.5 V to 18 V
NC = NO CONNECT
High output current: +30 mA/−20 mA
Wide temperature range: −40°C to +125°C
Figure 2. 8-Lead SOIC
(R Suffix)
APPLICATIONS
Precision data acquisition systems
High resolution data converters
Medical instruments
Industrial process control systems
Optical control circuits
Precision instruments
GENERAL DESCRIPTION
The ADR43x series is a family of XFET voltage references
featuring low noise, high accuracy, and low temperature drift
performance. Using ADI’s patented temperature drift curvature
correction and XFET (eXtra implanted junction FET) technology,
the ADR43x’s voltage change versus temperature nonlinearity is
minimized.
All versions are specified over the extended industrial tempera-
ture range (−40°C to +125°C).
Table 1. Selection Guide
Accuracy
VOUT (V) (mV)
Temperature Coefficient
(ppm/°C)
Model
ADR430B
ADR430A
ADR43±B
ADR43±A
ADR433B
ADR433A
ADR434B
ADR434A
ADR435B
ADR435A
ADR439B
ADR439A
2.048
2.048
2.500
2.500
3.000
3.000
4.096
4.096
5.000
5.000
4.500
4.500
±±
±3
±±
±3
±±.4
±4
±±.5
±5
±2
±6
3
±0
3
±0
3
±0
3
±0
3
±0
3
The XFET references operate at lower current (800 µA) and
supply headroom (2 V) than buried-Zener references. Buried-
Zener references require more than 5 V headroom for operations.
The ADR43x XFET references are the only low noise solutions
for 5 V systems.
The ADR43x series has the capability to source up to 30 mA
and sink up to 20 mA of output current. It also comes with a
TRIM terminal to adjust the output voltage over a 0.5% range
without compromising performance. The ADR43x is available
in the 8-lead mini SOIC and 8-lead SOIC packages.
±2
±5.4
±0
Rev. B
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703
www.analog.com
© 2004 Analog Devices, Inc. All rights reserved.
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
TABLE OF CONTENTS
Specifications..................................................................................... 3
ADR430 Electrical Characteristics............................................. 3
ADR431 Electrical Characteristics............................................. 4
ADR433 Electrical Characteristics............................................. 5
ADR434 Electrical Characteristics............................................. 6
ADR435 Electrical Characteristics............................................. 7
ADR439 Electrical Characteristics............................................. 8
Absolute Maximum Ratings............................................................ 9
Package Type................................................................................. 9
ESD Caution.................................................................................. 9
Typical Performance Characteristics ........................................... 10
Theory of Operation ...................................................................... 15
Basic Voltage Reference Connections...................................... 15
Noise Performance ..................................................................... 15
Turn-On Time ............................................................................ 15
Applications..................................................................................... 16
Output Adjustment .................................................................... 16
Reference for Converters in Optical Network Control
Circuits......................................................................................... 16
Negative Precision Reference without Precision Resistors... 16
High Voltage Floating Current Source.................................... 17
Kelvin Connections.................................................................... 17
Dual Polarity References ........................................................... 17
Programmable Current Source ................................................ 18
Programmable DAC Reference Voltage.................................. 18
Precision Voltage Reference for Data Converters.................. 19
Precision Boosted Output Regulator....................................... 19
Outline Dimensions....................................................................... 20
Ordering Guide .......................................................................... 21
REVISION HISTORY
9/04—Data Sheet Changed from Rev. A to Rev. B
Added New Grade ..............................................................Universal
Changes to Specifications................................................................ 3
Replaced Figure 3, Figure 4, Figure 5........................................... 10
Updated Ordering Guide............................................................... 21
6/04—Data Sheet Changed from Rev. 0 to Rev. A
Changes to Format .............................................................Universal
Changes to the Ordering Guide.................................................... 20
12/03—Revision 0: Initial Version
Rev. B | Page 2 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
SPECIFICATIONS
ADR430 ELECTRICAL CHARACTERISTICS
VIN = 4.1 V to 18 V, ILOAD = 0 mA, TA = 25°C, unless otherwise noted.
Table 2.
Parameter
Output Voltage
B Grade
Symbol
Conditions
Min
Typ
Max
Unit
VO
VO
2.047
2.045
2.048
2.048
2.049
2.05±
V
V
A Grade
Initial Accuracy
B Grade
B Grade
A Grade
A Grade
VOERR
VOERR
VOERR
VOERR
±
0.05
3
mV
%
mV
%
0.±5
Temperature Coefficient
SOIC-8 (B Grade)
SOIC-8 (A Grade)
MSOP-8
TCVO
TCVO
TCVO
∆VO/∆VIN
−40°C < TA < +±25°C
−40°C < TA < +±25°C
−40°C < TA < +±25°C
VIN = 4.± V to ±8 V
−40°C < TA < +±25°C
ILOAD = 0 mA to ±0 mA, VIN = 5.0 V
−40°C < TA < +±25°C
ILOAD = −±0 mA to 0 mA, VIN = 5.0 V
−40°C < TA < +±25°C
No load, −40°C < TA < +±25°C
0.± Hz to ±0.0 Hz
±
2
2
3
±0
±0
ppm/°C
ppm/°C
ppm/V
Line Regulation
5
20
±5
Load Regulation
∆VO/∆ILOAD
ppm/mA
±5
800
ppm/mA
µA
µV p-p
Quiescent Current
Voltage Noise
IIN
eN p-p
eN
560
3.5
60
Hz
nV√
Voltage Noise Density
Turn-On Settling Time
Long-Term Stability±
Output Voltage Hysteresis
Ripple Rejection Ratio
Short Circuit to GND
± kHz
tR
CIN = 0
±,000 h
±0
40
20
–70
40
µs
∆VO
VO_HYS
RRR
ISC
VIN
VIN − VO
ppm
ppm
dB
mA
V
fIN = ±0 kHz
Supply Voltage Operating Range
Supply Voltage Headroom
4.±
2
±8
V
± The long-term stability specification is noncumulative. The drift in subsequent ±,000 hour periods is significantly lower than in the first ±,000 hour period.
Rev. B | Page 3 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ADR431 ELECTRICAL CHARACTERISTICS
VIN = 4.5 V to 18 V, ILOAD = 0 mA, TA = 25°C, unless otherwise noted.
Table 3.
Parameter
Output Voltage
B Grade
Symbol
Conditions
Min
Typ
Max
Unit
VO
VO
2.499
2.497
2.500
2.500
2.50±
2.503
V
V
A Grade
Initial Accuracy
B Grade
B Grade
A Grade
A Grade
VOERR
VOERR
VOERR
VOERR
±
0.04
3
mV
%
mV
%
0.±3
Temperature Coefficient
SOIC-8 (B Grade)
SOIC-8 (A Grade)
MSOP-8
TCVO
TCVO
TCVO
∆VO/∆VIN
−40°C < TA < +±25°C
−40°C < TA < +±25°C
−40°C < TA < +±25°C
VIN = 4.5 V to ±8 V
±
2
2
3
±0
±0
ppm/°C
ppm/°C
ppm/°C
Line Regulation
−40°C < TA < +±25°C
5
20
±5
ppm/V
Load Regulation
∆VO/∆ILOAD
ILOAD = 0 mA to ±0 mA, VIN = 5.0 V
−40°C < TA < +±25°C
ILOAD = −±0 mA to 0 mA, VIN = 5.0 V
−40°C < TA < +±25°C
No load, −40°C < TA < +±25°C
0.± Hz to ±0.0 Hz
± kHz
ppm/mA
±5
800
ppm/mA
µA
µV p-p
Quiescent Current
IIN
580
3.5
80
Voltage Noise
eN p-p
eN
Hz
nV√
Voltage Noise Density
Turn-On Settling Time
Long-Term Stability±
Output Voltage Hysteresis
Ripple Rejection Ratio
Short Circuit to GND
tR
CIN = 0
±0
µs
∆VO
VO_HYS
RRR
ISC
±,000 h
40
20
−70
40
ppm
ppm
dB
mA
V
fIN = ±0 kHz
Supply Voltage Operating Range
Supply Voltage Headroom
VIN
VIN – VO
4.5
2
±8
V
± The long-term stability specification is noncumulative. The drift in subsequent ±,000 hour periods is significantly lower than in the first ±,000 hour period.
Rev. B | Page 4 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ADR433 ELECTRICAL CHARACTERISTICS
VIN = 5 V to 18 V, ILOAD = 0 mA , TA = 25°C, unless otherwise noted.
Table 4.
Parameter
Output Voltage
B Grade
Symbol
Conditions
Min
Typ
Max
Unit
VO
VO
2.9985
2.996
3.000
3.000
3.00±5
3.004
V
V
A Grade
Initial Accuracy
B Grade
B Grade
A Grade
A Grade
Temperature Coefficient
SOIC-8 (B Grade)
SOIC-8 (A Grade)
MSOP-8
VOERR
VOERR
VOERR
VOERR
TCVO
±.5
0.05
4
mV
%
mV
%
0.±3
−40°C < TA < +±25°C
−40°C < TA < +±25°C
−40°C < TA < +±25°C
VIN = 5 V to ±8 V
±
2
2
3
±0
±0
ppm/°C
ppm/°C
ppm/°C
Line Regulation
∆VO/∆VIN
−40°C < TA < +±25°C
ILOAD = 0 mA to ±0 mA, VIN = 6 V
−40°C < TA < +±25°C
ILOAD = −±0 mA to 0 mA, VIN = 6 V
−40°C < TA < +±25°C
No load, −40°C < TA < +±25°C
0.± Hz to ±0.0 Hz
5
20
±5
ppm/V
Load Regulation
∆VO/∆ILOAD
ppm/mA
±5
800
ppm/mA
µA
µV p-p
Quiescent Current
Voltage Noise
IIN
eN p-p
eN
590
3.75
90
Hz
nV√
Voltage Noise Density
Turn-On Settling Time
Long-Term Stability±
Output Voltage Hysteresis
Ripple Rejection Ratio
Short Circuit to GND
± kHz
tR
CIN = 0
±,000 h
±0
40
20
−70
40
µs
∆VO
VO_HYS
RRR
ISC
VIN
VIN − VO
ppm
ppm
dB
mA
V
fIN = ±0 kHz
Supply Voltage Operating Range
Supply Voltage Headroom
5
2
±8
V
±The long-term stability specification is noncumulative. The drift in subsequent ±,000 hour periods is significantly lower than in the first ±,000 hour period.
Rev. B | Page 5 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ADR434 ELECTRICAL CHARACTERISTICS
VIN = 6.1 V to 18 V, ILOAD = 0 mA, TA = 25°C, unless otherwise noted.
Table 5.
Parameter
Output Voltage
B Grade
Symbol
Conditions
Min
Typ
Max
Unit
VO
VO
4.0945
4.09±
4.096
4.096
4.0975
4.±0±
V
V
A Grade
Initial Accuracy
B Grade
B Grade
A Grade
A Grade
Temperature Coefficient
SOIC-8 (B Grade)
SOIC-8 (A Grade)
MSOP-8
VOERR
VOERR
VOERR
VOERR
TCVO
±.5
0.04
5
mV
%
mV
%
0.±3
−40°C < TA < +±25°C
−40°C < TA < +±25°C
−40°C < TA < +±25°C
VIN = 6.± V to ±8 V
−40°C < TA < +±25°C
ILOAD = 0 mA to ±0 mA, VIN = 7 V
−40°C < TA < +±25°C
ILOAD = −±0 mA to 0 mA, VIN = 7 V
−40°C < TA < +±25°C
No load, −40°C < TA < +±25°C
0.± Hz to ±0.0 Hz
±
2
2
3
±0
±0
ppm/°C
ppm/°C
ppm/°C
Line Regulation
∆VO/∆VIN
5
20
±5
ppm/V
Load Regulation
∆VO/∆ILOAD
ppm/mA
±5
800
ppm/mA
µA
µV p-p
Quiescent Current
Voltage Noise
IIN
eN p-p
eN
595
6.25
±00
±0
40
20
Hz
Voltage Noise Density
Turn-On Settling Time
Long-Term Stability±
Output Voltage Hysteresis
Ripple Rejection Ratio
Short Circuit to GND
± kHz
nV√
µs
tR
CIN = 0
±,000 h
∆VO
VO_HYS
RRR
ISC
VIN
VIN − VO
ppm
ppm
dB
mA
V
fIN = ±0 kHz
−70
40
Supply Voltage Operating Range
Supply Voltage Headroom
6.±
2
±8
V
± The long-term stability specification is noncumulative. The drift in subsequent ±,000 hour periods is significantly lower than in the first ±,000 hour period.
Rev. B | Page 6 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ADR435 ELECTRICAL CHARACTERISTICS
VIN = 7 V to 18 V, ILOAD = 0 mA, TA = 25°C, unless otherwise noted.
Table 6.
Parameter
Output Voltage
B Grade
Symbol
Conditions
Min
Typ
Max
Unit
VO
VO
4.998
4.994
5.000
5.000
5.002
5.006
V
V
A Grade
Initial Accuracy
B Grade
B Grade
A Grade
A Grade
Temperature Coefficient
SOIC-8 (B Grade)
SOIC-8 (A Grade)
MSOP-8
VOERR
VOERR
VOERR
VOERR
TCVO
2
0.04
6
mV
%
mV
%
0.±2
−40°C < TA < +±25°C
−40°C < TA < +±25°C
−40°C < TA < +±25°C
VIN = 7 V to ±8 V
−40°C < TA < +±25°C
ILOAD = 0 mA to ±0 mA, VIN = 8 V
−40°C < TA < +±25°C
ILOAD = −±0 mA to 0 mA, VIN = 8 V
−40°C < TA < +±25°C
No load, −40°C < TA < +±25°C
0.± Hz to ±0 Hz
±
2
2
3
±0
±0
ppm/°C
ppm/°C
ppm/°C
Line Regulation
∆VO/∆VIN
∆VO/∆ILOAD
5
20
±5
ppm/V
Load Regulation
ppm/mA
±5
800
ppm/mA
µA
µV p-p
Quiescent Current
Voltage Noise
IIN
eN p-p
eN
620
8
Hz
Voltage Noise Density
Turn-On Settling Time
Long-Term Stability±
Output Voltage Hysteresis
Ripple Rejection Ratio
Short Circuit to GND
± kHz
±±5
±0
40
20
−70
40
nV/√
µs
tR
CIN = 0
±,000 h
∆VO
VO_HYS
RRR
ISC
VIN
VIN − VO
ppm
ppm
dB
mA
V
fIN = ±0 kHz
Supply Voltage Operating Range
Supply Voltage Headroom
7
2
±8
V
± The long-term stability specification is noncumulative. The drift in subsequent ±,000 hour periods is significantly lower than in the first ±,000 hour period.
Rev. B | Page 7 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ADR439 ELECTRICAL CHARACTERISTICS
VIN = 6.5 V to 18 V, ILOAD = 0 mV, TA = 25°C, unless otherwise noted.
Table 7.
Parameter
Output Voltage
B Grade
Symbol
Conditions
Min
Typ
Max
Unit
VO
VO
4.498
4.4946
4.500
4.500
4.502
4.5054
V
V
A Grade
Initial Accuracy
B Grade
B Grade
A Grade
A Grade
Temperature Coefficient
SOIC-8 (B Grade)
SOIC-8 (A Grade)
MSOP-8
VOERR
VOERR
VOERR
VOERR
TCVO
2
mV
%
mV
%
0.04
5.4
0.±2
−40°C < TA < +±25°C
−40°C < TA < +±25°C
−40°C < TA < +±25°C
VIN = 6.5 V to ±8 V
±
2
2
3
±0
±0
ppm/°C
ppm/°C
ppm/°C
Line Regulation
∆VO/∆VIN
−40°C < TA < +±25°C
ILOAD = 0 mA to ±0 mA, VIN = 6.5 V
−40°C < TA < +±25°C
ILOAD = −±0 mA to 0 mA, VIN = 6.5 V
−40°C < TA < +±25°C
No load, −40°C < TA < +±25°C
0.± Hz to ±0.0 Hz
5
20
±5
ppm/V
Load Regulation
∆VO/∆ILOAD
ppm/mA
±5
800
ppm/mA
µA
µV p-p
Quiescent Current
Voltage Noise
IIN
eN p-p
eN
600
7.5
±±0
±0
40
20
Hz
Voltage Noise Density
Turn-On Settling Time
Long-Term Stability±
Output Voltage Hysteresis
Ripple Rejection Ratio
Short Circuit to GND
± kHz
nV/√
tR
CIN = 0
±,000 h
µs
∆VO
VO_HYS
RRR
ISC
VIN
VIN − VO
ppm
ppm
dB
mA
V
fIN = ±0 kHz
−70
40
Supply Voltage Operating Range
Supply Voltage Headroom
6.5
2
±8
V
± The long-term stability specification is noncumulative. The drift in subsequent ±,000 hour periods is significantly lower than in the first ±,000 hour period.
Rev. B | Page 8 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ABSOLUTE MAXIMUM RATINGS
@ 25°C, unless otherwise noted.
Table 8.
Parameter
Supply Voltage
Output Short-Circuit Duration to GND
Storage Temperature Range (R, RM Packages)
Operating Temperature Range
Junction Temperature Range
Lead Temperature Range (Soldering, 60 s)
PACKAGE TYPE
Rating
Table 9.
20 V
Indefinite
−65°C to +±25°C
−40°C to +±25°C
−65°C to +±50°C
300°C
1
Package Type
8-Lead SOIC (R)
8-Lead MSOP (RM)
θJC
Unit
°C/W
°C/W
θJA
±30
±90
43
± θJA is specified for worst-case conditions (device soldered in circuit board for
surface-mount packages).
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions beyond those indicated in the operational
sections of this specification is not implied. Absolute maximum
ratings apply individually only, not in combination.
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on
the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.
Rev. B | Page 9 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
TYPICAL PERFORMANCE CHARACTERISTICS
Default conditions: 5 V, CL = 5 pF, G = 2, Rg = Rf = 1 kΩ, RL = 2 kΩ, VO = 2 V p-p, Frequency = 1 MHz, TA = 25°C.
0.8
2.5009
0.7
0.6
2.5007
2.5005
2.5003
2.5001
2.4999
2.4997
2.4995
+125°C
+25°C
–40°C
0.5
0.4
0.3
–40 –25 –10
5
20
35
50
65
80
95 110 125
4
6
8
10
12
14
16
TEMPERATURE (°C)
INPUT VOLTAGE (V)
Figure 6. ADR435 Supply Current vs. Input Voltage
Figure 3. ADR431 VOUT vs. Temperature
700
650
600
550
500
450
400
4.0980
4.0975
4.0970
4.0965
4.0960
4.0955
4.0950
–40 –25 –10
5
20
35
50
65
80
95 110 125
–40 –25 –10
5
20
35
50
65
80
95 110 125
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 7. ADR435 Supply Current vs. Temperature
Figure 4. ADR434 VOUT vs. Temperature
0.60
0.58
0.56
0.54
0.52
0.50
0.48
0.46
0.44
0.42
0.40
5.0025
5.0020
5.0015
5.0010
5.0005
5.0000
4.9995
4.9990
+125°C
+25°C
–40°C
–40 –25 –10
5
20
35
50
65
80
95 110 125
6
8
10
12
14
16
18
TEMPERATURE (°C)
INPUT VOLTAGE (V)
Figure 8. ADR431 Supply Current vs. Input Voltage
Figure 5. ADR435 VOUT vs. Temperature
Rev. B | Page ±0 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
610
580
550
520
490
460
430
400
2.5
2.0
–40°C
1.5
+25°C
1.0
+125°C
0.5
0
–10
–5
0
5
10
–40 –25 –10
5
20
35
50
65
80
95 110 125
TEMPERATURE (°C)
LOAD CURRENT (mA)
Figure 9. ADR431 Supply Current vs. Temperature
Figure 12. ADR431 Minimum Input/Output
Differential Voltage vs. Load Current
1.9
15
12
9
I
= 0mA to 10mA
L
NO LOAD
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
6
3
0
–40 –25 –10
5
20
35
50
65
80
95 110 125
–40 –25 –10
5
20
35
50
65
80
95 110 125
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 10. ADR431 Load Regulation vs. Temperature
Figure 13. ADR431 Minimum Headroom vs. Temperature
15
12
9
2.5
2.0
1.5
1.0
0.5
0
I
= 0mA to 10mA
L
–40°C
+25°C
6
+125°C
3
0
–10
–5
0
5
10
–40 –25 –10
5
20
35
50
65
80
95 110 125
TEMPERATURE (°C)
LOAD CURRENT (mA)
Figure 14. ADR435 Minimum Input/Output
Differential Voltage vs. Load Current
Figure 11. ADR435 Load Regulation vs. Temperature
Rev. B | Page ±± of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
1.9
C
= 0.01µF
LOAD
NO LOAD
NO INPUT CAPACITOR
V
= 1V/DIV
OUT
1.7
1.5
1.3
1.1
0.9
V
= 2V/DIV
IN
TIME = 4µs/DIV
–40 –25 –10
5
20
35
50
65
80
95 110 125
TEMPERATURE (°C)
Figure 15. ADR435 Minimum Headroom vs. Temperature
Figure 18. ADR431 Turn-On Response, 0.01 µF Load Capacitor
20
16
12
8
C
= 0.01µF
IN
V
= 7V TO 18V
IN
NO LOAD
V
= 1V/DIV
OUT
V
= 2V/DIV
4
IN
TIME = 4µs/DIV
0
–4
–40 –25 –10
5
20
35
50
65
80
95 110 125
TEMPERATURE (°C)
Figure 16. ADR435 Line Regulation vs. Temperature
Figure 19. ADR431 Turn-Off Response
C
= 0.01µF
LINE
INTERRUPTION
IN
BYPASS CAPACITOR = 0µF
NO LOAD
V
= 1V/DIV
OUT
500mV/DIV
V
IN
V
= 50mV/DIV
OUT
V
= 2V/DIV
IN
TIME = 100µs/DIV
TIME = 4µs/DIV
Figure 17. ADR431 Turn-On Response
Figure 20. ADR431 Line Transient Response—No Capacitors
Rev. B | Page ±2 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
LINE
INTERRUPTION
BYPASS CAPACITOR = 0.1µF
500mV/DIV
V
IN
V
= 50mV/DIV
OUT
2µV/DIV
TIME = 1s/DIV
TIME = 100µs/DIV
Figure 21. ADR431 Line Transient Response—0.1 µF Bypass Capacitor
Figure 24. ADR435 0.1 Hz to 10.0 Hz Voltage Noise
1µV/DIV
50µV/DIV
TIME = 1s/DIV
TIME = 1s/DIV
Figure 22. ADR431 0.1 Hz to 10.0 Hz Voltage Noise
Figure 25. ADR435 10 Hz to 10 kHz Voltage Noise
14
12
10
8
6
50µV/DIV
4
TIME = 1s/DIV
2
0
–120 –90 –70 –50 –30 –10 10
30
50
70
90 120
DEVIATION (PPM)
Figure 23. ADR431 10 Hz to 10 kHz Voltage Noise
Figure 26. ADR431 Typical Hysteresis
Rev. B | Page ±3 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
50
45
40
35
30
25
20
15
10
5
10
–10
–30
–50
–70
ADR435
–90
ADR433
–110
–130
–150
ADR430
0
100
1k
10k
FREQUENCY (Hz)
100k
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 27. Output Impedance vs. Frequency
Figure 28. Ripple Rejection Ratio
Rev. B | Page ±4 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
THEORY OF OPERATION
The ADR43x series of references uses a new reference generation
technique known as XFET (eXtra implanted junction FET).
This technique yields a reference with low supply current, good
thermal hysteresis, and exceptionally low noise. The core of the
XFET reference consists of two junction field-effect transistors
(JFETs), one of which has an extra channel implant to raise its
pinch-off voltage. By running the two JFETs at the same drain
current, the difference in pinch-off voltage can be amplified and
used to form a highly stable voltage reference.
The ADR43x family of references is guaranteed to deliver load
currents to 10 mA with an input voltage that ranges from 4.5 V
to 18 V. When these devices are used in applications at higher
currents, users should use the following equation to account for
the temperature effects due to the power dissipation increases.
TJ =PD × θJA + TA
(2)
where:
TJ and TA are the junction and ambient temperatures,
respectively.
PD is the device power dissipation.
The intrinsic reference voltage is around 0.5 V with a negative
temperature coefficient of about –120 ppm/°C. This slope is
essentially constant to the dielectric constant of silicon and can
be closely compensated by adding a correction term generated
in the same fashion as the proportional-to-temperature (PTAT)
term used to compensate band gap references. The big advantage
of an XFET reference is that the correction term is some 30 times
lower (therefore, requiring less correction) than for a band gap
reference, resulting in much lower noise, because most of the
noise of a band gap reference comes from the temperature
compensation circuitry.
θJA is the device package thermal resistance.
BASIC VOLTAGE REFERENCE CONNECTIONS
Voltage references, in general, require a bypass capacitor
connected from VOUT to GND. The circuit in Figure 30
illustrates the basic configuration for the ADR43x family of
references. Other than a 0.1 µF capacitor at the output to help
improve noise suppression, a large output capacitor at the
output is not required for circuit stability.
Figure 29 shows the basic topology of the ADR43x series. The
temperature correction term is provided by a current source
with a value designed to be proportional to absolute temperature.
The general equation is
1
TP
TP
8
7
6
V
IN
NIC
2
3
4
ADR43x
TOP VIEW
(Not to Scale)
+
OUTPUT
10µF
NIC
0.1µF
0.1µF
5
TRIM
VOUT = G ×
ΔVP − R1 × IPTAT
(1)
NIC = NO INTERNAL CONNECTION
TP = TEST PIN (DO NOT CONNECT)
where:
G is the gain of the reciprocal of the divider ratio.
∆VP is the difference in pinch-off voltage between the two JFETs.
PTAT is the positive temperature coefficient correction current.
Figure 30. Basic Voltage Reference Configuration
NOISE PERFORMANCE
I
The noise generated by the ADR43x family of references is
typically less than 3.75 µV p-p over the 0.1 Hz to 10.0 Hz band
for ADR430, ADR431, and ADR433. Figure 22 shows the 0.1
Hz to 10 Hz noise of the ADR431, which is only 3.5 µV p-p. The
noise measurement is made with a band-pass filter made of a
2-pole high-pass filter with a corner frequency at 0.1 Hz and a
2-pole low-pass filter with a corner frequency at 10.0 Hz.
ADR43x devices are created by on-chip adjustment of R2 and
R3 to achieve 2.048 V or 2.500 V, respectively, at the reference
output.
V
IN
I
I
1
1
ADR43x
I
PTAT
TURN-ON TIME
V
OUT
R2
Upon application of power (cold start), the time required for
the output voltage to reach its final value within a specified
error band is defined as the turn-on settling time. Two compo-
nents normally associated with this are the time for the active
circuits to settle and the time for the thermal gradients on the
chip to stabilize. Figure 17 and Figure 18 show the turn-on
settling time for the ADR431.
*
∆V
P
R3
R1
*EXTRA CHANNEL IMPLANT
= G(∆V – R1
V
OUT
×
I
)
PTAT
P
GND
Figure 29. Simplified Schematic Device
Power Dissipation Considerations
Rev. B | Page ±5 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
APPLICATIONS
OUTPUT ADJUSTMENT
SOURCE FIBER
GIMBAL + SENSOR
DESTINATION
FIBER
The ADR43x trim terminal can be used to adjust the output
LASER BEAM
voltage over a 0.5% range. This feature allows the system
designer to trim system errors out by setting the reference to a
voltage other than the nominal. This is also helpful if the part is
used in a system at temperature to trim out any error. Adjustment
of the output has negligible effect on the temperature perform-
ance of the device. To avoid degrading temperature coefficients,
both the trimming potentiometer and the two resistors need to
be low temperature coefficient types, preferably <100 ppm/°C.
ACTIVATOR
LEFT
ACTIVATOR
RIGHT
MEMS MIRROR
PREAMP
AMPL
AMPL
DAC
ADR431
ADR431
ADR431
CONTROL
ELECTRONICS
DAC
ADC
INPUT
DSP
V
IN
GND
OUTPUT
= ±0.5%
V
O
V
O
Figure 32. All-Optical Router Network
ADR43x
R1
470kΩ
R
10kΩ
P
NEGATIVE PRECISION REFERENCE WITHOUT
PRECISION RESISTORS
TRIM
GND
10kΩ (ADR420)
15kΩ (ADR421)
R2
In many current-output CMOS DAC applications where the
output signal voltage must be of the same polarity as the
reference voltage, it is often required to reconfigure a current-
switching DAC into a voltage-switching DAC through the use
of a 1.25 V reference, an op amp, and a pair of resistors. Using a
current-switching DAC directly requires an additional opera-
tional amplifier at the output to re-invert the signal. A negative
voltage reference is then desirable from the standpoint that an
additional operational amplifier is not required for either
re-inversion (current-switching mode) or amplification
(voltage-switching mode) of the DAC output voltage. In
general, any positive voltage reference can be converted into a
negative voltage reference through the use of an operational
amplifier and a pair of matched resistors in an inverting
configuration. The disadvantage to this approach is that the
largest single source of error in the circuit is the relative
matching of the resistors used.
Figure 31. Output Trim Adjustment
REFERENCE FOR CONVERTERS IN OPTICAL
NETWORK CONTROL CIRCUITS
In the upcoming high capacity, all-optical router network,
Figure 32 employs arrays of micromirrors to direct and route
optical signals from fiber to fiber without first converting them
to electrical form, which reduces the communication speed.
The tiny micromechanical mirrors are positioned so that each is
illuminated by a single wavelength that carries unique informa-
tion and can be passed to any desired input and output fiber.
The mirrors are tilted by the dual-axis actuators controlled by
precision ADCs and DACs within the system. Due to the
microscopic movement of the mirrors, not only is the precision
of the converters important, but the noise associated with these
controlling converters is also extremely critical, because total
noise within the system can be multiplied by the number of
converters employed. As a result, to maintain the stability of the
control loop for this application, the ADR43x is necessary due
to its exceptionally low noise.
A negative reference can easily be generated by adding a
precision op amp and configuring it as shown in Figure 33.
VOUT is at virtual ground and, therefore, the negative reference
can be taken directly from the output of the op amp. The op
amp must be dual supply, have low offset and rail-to-rail
capability, if negative supply voltage is close to the reference
output.
Rev. B | Page ±6 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
+V
DD
V
IN
R
LW
V
OUT
2
V
IN
SENSE
2
ADR43x
R
LW
V
IN
A1
V
OUT
+
V
OUT
6
FORCE
V
OUT
6
R
L
GND
4
ADR43x
A1 = OP191
GND
4
Figure 35. Advantage of Kelvin Connection
A1
–V
REF
DUAL POLARITY REFERENCES
–V
A1 = OP777, OP193
DD
Dual polarity references can easily be made with an op amp and
a pair of resistors. In order not to defeat the accuracy obtained
by ADR43x, it is imperative to match the resistance tolerance as
well as the temperature coefficient of all the components.
Figure 33. Negative Reference
HIGH VOLTAGE FLOATING CURRENT SOURCE
The circuit in Figure 34 can be used to generate a floating
current source with minimal self-heating. This particular
configuration can operate on high supply voltages determined
by the breakdown voltage of the N-channel JFET.
V
IN
2
1
µF
0.1µF
V
V
OUT
6
5
+5V
IN
R1
10k
R2
10k
Ω
ADR435
Ω
U1
+10V
V+
+V
S
GND
TRIM
SST111
VISHAY
4
OP1177
U2
V–
–5V
V
IN
R3
5k
ADR43x
Ω
V
–10V
OUT
2N3904
OP90
Figure 36. +5 V and −5 V References Using ADR435
GND
+2.5V
R
L
2.1kΩ
+10V
2
–V
S
V
V
IN
6
5
OUT
Figure 34. High Voltage Floating Current Source
R1
5.6kΩ
ADR435
U1
KELVIN CONNECTIONS
TRIM
GND
4
In many portable instrumentation applications where PC board
cost and area go hand-in-hand, circuit interconnects are very
often of dimensionally minimum width. These narrow lines can
cause large voltage drops if the voltage reference is required to
provide load currents to various functions. In fact, a circuit’s
interconnects can exhibit a typical line resistance of 0.45 mΩ/
square (1 oz. Cu, for example). Force and sense connections,
also referred to as Kelvin connections, offer a convenient
method of eliminating the effects of voltage drops in circuit
wires. Load currents flowing through wiring resistance produce
an error (VERROR = R × IL) at the load. However, the Kelvin
connection of Figure 35 overcomes the problem by including
the wiring resistance within the forcing loop of the op amp.
Because the op amp senses the load voltage, the op amp loop
control forces the output to compensate for the wiring error and
to produce the correct voltage at the load.
R2
5.6kΩ
V+
OP1177
U2
V–
–2.5V
–10V
Figure 37. +2.5 V and −2.5 V References Using ADR435
Rev. B | Page ±7 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
PROGRAMMABLE CURRENT SOURCE
PROGRAMMABLE DAC REFERENCE VOLTAGE
Together with a digital potentiometer and a Howland current
pump, ADR435 forms the reference source for a programmable
current as
With a multichannel DAC such as a quad 12-bit voltage output
DAC AD7398, one of its internal DACs and an ADR43x voltage
reference can be used as a common programmable VREFX for the
rest of the DACs. The circuit configuration is shown in Figure 39.
R2 +R2
⎛
⎜
⎞
⎟
A
B
R1
R2B
⎜
⎟
IL =
×VW
(3)
R2
⎜
⎜
⎝
⎟
⎟
⎠
± 0.1%
V
REFA
R1 ± 0.1%
V
OUTA
V
REF
DAC A
and
V
IN
ADR436
D
V
REFB
V
V
OUTB
OUTC
VW
=
×VREF
(4)
V
= V
(D )
2N
OB
REFX B
DAC B
where:
D is the decimal equivalent of the input code.
N is the number of bits.
V
REFC
V
V
= V
(D
(D
)
OC
REFX
REFX
C
DAC C
′
′
In addition, R1 and R2 must be equal to R1 and R2A + R2B,
respectively. R2B in theory can be made as small as needed to
achieve the necessary current within the A2 output current
driving capability. In this example, OP2177 can deliver a maxi-
mum of 10 mA. Because the current pump employs both positive
and negative feedback, capacitors C1 and C2 are needed to
ensure that the negative feedback prevails and, therefore, avoids
oscillation. This circuit also allows bidirectional current flow if
the inputs VA and VB of the digital potentiometer are supplied
with the dual polarity references, as shown previously.
V
REFD
V
OUTD
= V
)
D
OD
DAC D
AD7398
Figure 39. Programmable DAC Reference
The relationship of VREFX to VREF depends on the digital code
and the ratio of R1 and R2, and is given by
C1
10pF
R2
R1
⎛
⎝
⎞
⎟
⎠
VREF × 1+
⎜
VREFX
=
(5)
R1'
50kΩ
R2'
1kΩ
V
DD
2
D
R2
R1
⎛
⎜
⎝
⎞
⎠
1+
×
⎟
2N
V
DD
V
IN
TRIM
5
6
AD5232
U2
DIGITAL
where:
V+
ADR435
D is the decimal equivalent of input code.
N is the number of bits.
U1
C2
10pF
POTENTIOMETER
OP2177
A2
V–
V
DD
V
OUT
GND
4
A
R2
10Ω
B
V
V
REF is the applied external reference.
REFX is the reference voltage for DAC A to DAC D.
U2
V+
R1
50kΩ
V
SS
W
B
OP2177
A1
R2
A
V–
1kΩ
+
VL
–
Table 10. VREFX vs. R1 and R2
LOAD
GND
V
SS
R1, R2
Digital Code
VREF
IL
R± = R2
R± = R2
R± = R2
R± = 3R2
R± = 3R2
R± = 3R2
0000 0000 0000
±000 0000 0000
±±±± ±±±± ±±±±
0000 0000 0000
±000 0000 0000
±±±± ±±±± ±±±±
2 VREF
±.3 VREF
VREF
4 VREF
±.6 VREF
VREF
Figure 38. Programmable Current Source
Rev. B | Page ±8 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
PRECISION VOLTAGE REFERENCE FOR
DATA CONVERTERS
PRECISION BOOSTED OUTPUT REGULATOR
A precision voltage output with boosted current capability can
be realized with the circuit shown in Figure 41. In this circuit,
U2 forces VO to be equal to VREF by regulating the turn on of
N1. Therefore, the load current is furnished by VIN. In this
configuration, a 50 mA load is achievable at VIN of 5 V.
Moderate heat is generated on the MOSFET, and higher current
can be achieved with a replacement of the larger device. In
addition, for a heavy capacitive load with step input, a buffer
may be added at the output to enhance the transient response.
The ADR43x family has a number of features that make it ideal
for use with ADCs and DACs. The exceptional low noise, tight
temperature coefficient, and high accuracy characteristics make
the ADR43x ideal for low noise applications such as cellular
base station applications.
Another example of ADC for which the ADR431 is well suited
is the AD7701. Figure 40 shows the ADR431 used as the
precision reference for this converter. The AD7701 is a 16-bit
ADC with on-chip digital filtering intended for the
measurement of wide dynamic range and low frequency signals
such as those representing chemical, physical, or biological
processes. It contains a charge-balancing (Σ-∆) ADC, a
calibration microcontroller with on-chip static RAM, a clock
oscillator, and a serial communications port.
N1
V
IN
V
O
R
25Ω
L
5V
2
U1
2N7002
U2
V
IN
6
5
V
+
OUT
V+
TRIM
AD8601
+5V
ANALOG
GND
4
V–
–
SUPPLY
0.1µF
10µF
AD7701
ADR431
AV
V
DV
DD
DD
0.1µF
SLEEP
MODE
V
IN
Figure 41. Precision Boosted Output Regulator
V
OUT
REF
DATA READY
DRDV
CS
0.1µF
ADR431
READ (TRANSMIT)
SERIAL CLOCK
SERIAL CLOCK
GND
SCLK
SDATA
CLKIN
RANGES
SELECT
BP/UP
CAL
CLKOUT
SC1
CALIBRATE
ANALOG
INPUT
A
IN
SC2
ANALOG
GROUND
AGND
DGND
0.1µF
0.1µF
DV
SS
AV
SS
–5V
ANALOG
SUPPLY
10µF
0.1µF
Figure 40. Voltage Reference for 16-Bit ADC AD7701
Rev. B | Page ±9 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
OUTLINE DIMENSIONS
3.00
BSC
8
5
4
4.90
BSC
3.00
BSC
PIN 1
0.65 BSC
1.10 MAX
0.15
0.00
0.80
0.60
0.40
8°
0°
0.38
0.22
0.23
0.08
COPLANARITY
0.10
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MO-187AA
Figure 42. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
5.00 (0.1968)
4.80 (0.1890)
8
1
5
4
6.20 (0.2440)
5.80 (0.2284)
4.00 (0.1574)
3.80 (0.1497)
1.27 (0.0500)
BSC
0.50 (0.0196)
0.25 (0.0099)
× 45°
1.75 (0.0688)
1.35 (0.0532)
0.25 (0.0098)
0.10 (0.0040)
8°
0.51 (0.0201)
0.31 (0.0122)
0° 1.27 (0.0500)
COPLANARITY
0.10
0.25 (0.0098)
0.17 (0.0067)
SEATING
PLANE
0.40 (0.0157)
COMPLIANT TO JEDEC STANDARDS MS-012AA
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
Figure 43. 8-Lead Standard Small Outline Package [SOIC]
Narrow Body (R-8)
Dimensions shown in millimeters and (inches)
Rev. B | Page 20 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
ORDERING GUIDE
Initial
Accuracy
Temperature
Coefficient
Package
Output
Package
Description
Parts
per Reel
Temperature
Branding Range
Model
Voltage (VO)
mV (%)
(ppm/°C)
ADR430AR
ADR430AR-REEL7
ADR430ARM
ADR430ARM-REEL7 2.048
ADR430BR
ADR430BR-REEL7
ADR43±AR
ADR43±AR-REEL7
ADR43±ARM
ADR43±ARM-REEL7 2.500
ADR43±BR
ADR43±BR-REEL7
ADR433AR
ADR433AR-REEL7
ADR433ARM
ADR433ARM-REEL7 3.000
ADR433BR
ADR433BR-REEL7
ADR434AR
ADR434AR-REEL7
ADR434ARM
ADR434ARM-REEL7 4.096
ADR434BR
ADR434BR-REEL7
ADR435AR
ADR435AR-REEL7
ADR435ARM
ADR435ARM-REEL7 5.000
ADR435BR
ADR435BR-REEL7
ADR439AR
ADR439AR-REEL7
ADR439ARM
ADR439ARM-REEL7 4.500
ADR439BR
2.048
2.048
2.048
3
3
3
3
±
±
0.±5
0.±5
0.±5
0.±5
0.05
0.05
0.±2
0.±2
0.±2
0.±2
0.04
0.04
0.±2
0.±2
0.±2
0.±2
0.05
0.05
0.±3
0.±3
0.±3
0.±3
0.04
0.04
0.±2
0.±2
0.±2
0.±2
0.04
0.04
0.±2
0.±2
0.±2
0.±2
0.04
0.04
±0
±0
±0
±0
3
8-lead SOIC
8-Lead SOIC
8-Lead MSOP
8-Lead MSOP
8-lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead MSOP
8-Lead MSOP
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead MSOP
8-Lead MSOP
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead MSOP
8-Lead MSOP
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead MSOP
8-Lead MSOP
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead SOIC
8-Lead MSOP
8-Lead MSOP
8-Lead SOIC
8-Lead SOIC
N/A
3,000
N/A
±,000
N/A
3,000
N/A
3,000
N/A
±,000
N/A
3,000
N/A
3,000
N/A
±,000
N/A
3,000
N/A
3,000
N/A
±,000
N/A
3,000
N/A
3,000
N/A
±,000
N/A
3,000
N/A
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
–40°C to +±25°C
RHA
RHA
2.048
2.048
2.500
2.500
2.500
3
3
3
3
3
±
±
±0
±0
±0
±0
3
RJA
RJA
2.500
2.500
3.000
3.000
3.000
3
4
4
4
4
±.5
±.5
5
5
5
±0
±0
±0
±0
3
RKA
RKA
3.000
3.000
4.096
4.096
4.096
3
±0
±0
±0
±0
3
RLA
RLA
5
4.096
4.096
5.000
5.000
5.000
±.5
±.5
6
6
6
6
2
2
3
±0
±0
±0
±0
3
RMA
RMA
5.000
5.000
4.500
4.500
4.500
3
5.4
5.4
5.4
5.4
2
±0
±0
±0
±0
3
3,000
N/A
±,000
N/A
RNA
RNA
4.500
4.500
ADR439BR-REEL7
2
3
3,000
Rev. B | Page 2± of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
NOTES
Rev. B | Page 22 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
NOTES
Rev. B | Page 23 of 24
ADR430/ADR431/ADR433/ADR434/ADR435/ADR439
NOTES
©
2004 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D04500–0–9/04(B)
Rev. B | Page 24 of 24
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