Datasheet ADR430 Datasheet (Analog Devices)

Ultralow Noise XFET® Voltage References

with Current Sink and Source Capability

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

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

B Grade: 3 ppm/°C max
Load regulation: 15 ppm/mA
Line regulation: 20 ppm/V
Wide operating range

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

ADR439: 6.5 V to 18 V
High output current: +30 mA/−20 mA
Wide temperature range: −40°C to +125°C

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.

The XFET references operate at lower current (800 µA) and
supply headroom (2 V) than buried-Zener references. Buried­Zener 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.

PIN CONFIGURATIONS

1

TP

ADR43x

V

2

IN

TOP VIEW

NC

3

(Not to Scale)

GND

4

NC = NO CONNECT

Figure 1. 8-Lead MSOP

(RM Suffix)

TP

1

ADR43x

V

2

IN

TOP VIEW

3

NC

(Not to Scale)

GND

4

NC = NO CONNECT

Figure 2. 8-Lead SOIC

All versions are specified over the extended industrial tempera­ture range (−40°C to +125°C).

Table 1. Selection Guide

Accuracy

Model V

OUT

(V)

(mV)

ADR430B 2.048 ±1 3
ADR430A 2.048 ±3 10
ADR431B 2.500 ±1 3
ADR431A 2.500 ±3 10
ADR433B 3.000 ±1.4 3
ADR433A 3.000 ±4 10
ADR434B 4.096 ±1.5 3
ADR434A 4.096 ±5 10
ADR435B 5.000 ±2 3
ADR435A 5.000 ±6 10
ADR439B 4.500 ±2 3
ADR439A 4.500 ±5.4 10

(R Suffix)

8

TP
NC

7

V

6

OUT

TRIM

5

04500-0-001

TP

8
7

NC

6

V

OUT

5

TRIM

04500-0-041

Temperature Coefficient
(ppm/°C)

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: [phone]
Fax: [phone] © 2004 Analog Devices, Inc. All rights reserved.

www.analog.com

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

TABLE OF CONTENTS

Specifications..................................................................................... 3

Applications..................................................................................... 16

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

Tur n -O n Tim e ............................................................................ 15

Output Adjustment .................................................................... 16

Reference for Converters in Optical Network Control
Circuits

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

......................................................................................... 16

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, I

Table 2.

Parameter Symbol Conditions Min Typ Max Unit

Output Voltage

B Grade V
A Grade V

Initial Accuracy

B Grade V
B Grade V
A Grade V
A Grade V

Temperature Coefficient

SOIC-8 (B Grade) TCV
SOIC-8 (A Grade) TCV
MSOP-8 TCV

Line Regulation ∆VO/∆V

−40°C < TA < +125°C 5 20 ppm/V
Load Regulation ∆VO/∆I

−40°C < TA < +125°C 15 ppm/mA
I

−40°C < TA < +125°C 15 ppm/mA
Quiescent Current I
Voltage Noise eN p-p 0.1 Hz to 10.0 Hz 3.5 µV p-p
Voltage Noise Density e
Turn-On Settling Time t
Long-Term Stability
Output Voltage Hysteresis V
Ripple Rejection Ratio RRR fIN = 10 kHz –70 dB
Short Circuit to GND I
Supply Voltage Operating Range V
Supply Voltage Headroom VIN − V

1

The long-term stability specification is noncumulative. The drift in subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.

= 0 mA, TA = 25°C, unless otherwise noted.

LOAD

O

O

OERR

OERR

OERR

OERR

O

O

O

IN

LOAD

IN

N

1

∆V

SC

R

O

O_HYS

IN

O

2.047 2.048 2.049 V

2.045 2.048 2.051 V

1 mV

0.05 %
3 mV

0.15 %

−40°C < TA < +125°C 1 3 ppm/°C

−40°C < TA < +125°C 2 10

−40°C < TA < +125°C 2 10 ppm/°C
VIN = 4.1 V to 18 V

I

LOAD

LOAD

No load, −40°C < TA < +125°C 560 800 µA

1 kHz 60
CIN = 0 10 µs
1,000 h 40 ppm
20 ppm

40 mA

4.1 18 V
2 V

= 0 mA to 10 mA, VIN = 5.0 V

= −10 mA to 0 mA, VIN = 5.0 V

nV√

Hz

Rev. B | Page 3 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

ADR431 ELECTRICAL CHARACTERISTICS

VIN = 4.5 V to 18 V, I

Table 3.

Parameter Symbol Conditions Min Typ Max Unit

Output Voltage

B Grade V
A Grade V

Initial Accuracy

B Grade V
B Grade V
A Grade V
A Grade V

Temperature Coefficient

SOIC-8 (B Grade) TCV
SOIC-8 (A Grade) TCV
MSOP-8 TCV

Line Regulation ∆VO/∆VIN VIN = 4.5 V to 18 V

−40°C < TA < +125°C 5 20 ppm/V
Load Regulation ∆VO/∆I

−40°C < TA < +125°C 15 ppm/mA
I

−40°C < TA < +125°C 15 ppm/mA
Quiescent Current IIN No load, −40°C < TA < +125°C 580 800 µA
Voltage Noise eN p-p 0.1 Hz to 10.0 Hz 3.5 µV p-p
Voltage Noise Density e
Turn-On Settling Time t
Long-Term Stability1 ∆VO 1,000 h 40 ppm
Output Voltage Hysteresis V
Ripple Rejection Ratio RRR fIN = 10 kHz −70 dB
Short Circuit to GND ISC 40 mA
Supply Voltage Operating Range VIN 4.5 18 V
Supply Voltage Headroom VIN – VO 2 V

1

The long-term stability specification is noncumulative. The drift in subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.

= 0 mA, TA = 25°C, unless otherwise noted.

LOAD

O

O

OERR

OERR

OERR

0.13 %

OERR

O

O

O

LOAD

N

R

20 ppm

O_HYS

2.499 2.500 2.501 V

2.497 2.500 2.503 V

1 mV

0.04 %
3 mV

−40°C < TA < +125°C 1 3 ppm/°C

−40°C < TA < +125°C 2 10 ppm/°C

−40°C < TA < +125°C 2 10 ppm/°C

I

LOAD

LOAD

1 kHz 80
CIN = 0 10 µs

= 0 mA to 10 mA, VIN = 5.0 V

= −10 mA to 0 mA, VIN = 5.0 V

nV√

Hz

Rev. B | Page 4 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

ADR433 ELECTRICAL CHARACTERISTICS

VIN = 5 V to 18 V, I

Table 4.

Parameter Symbol Conditions Min Typ Max Unit

Output Voltage

B Grade V
A Grade V

Initial Accuracy

B Grade V
B Grade V
A Grade V
A Grade V

Temperature Coefficient TCVO

SOIC-8 (B Grade) −40°C < TA < +125°C 1 3 ppm/°C
SOIC-8 (A Grade) −40°C < TA < +125°C 2 10 ppm/°C
MSOP-8 −40°C < TA < +125°C 2 10 ppm/°C

Line Regulation ∆VO/∆VIN VIN = 5 V to 18 V

−40°C < TA < +125°C 5 20 ppm/V
Load Regulation ∆VO/∆I

−40°C < TA < +125°C 15 ppm/mA
I

−40°C < TA < +125°C 15 ppm/mA
Quiescent Current IIN No load, −40°C < TA < +125°C 590 800 µA
Voltage Noise eN p-p 0.1 Hz to 10.0 Hz 3.75 µV p-p
Voltage Noise Density eN 1 kHz 90
Turn-On Settling Time tR CIN = 0 10 µs
Long-Term Stability
Output Voltage Hysteresis V
Ripple Rejection Ratio RRR fIN = 10 kHz −70 dB
Short Circuit to GND ISC 40 mA
Supply Voltage Operating Range VIN 5 18 V
Supply Voltage Headroom VIN − VO 2 V

1

The long-term stability specification is noncumulative. The drift in subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.

= 0 mA , TA = 25°C, unless otherwise noted.

LOAD

O

O

OERR

OERR

OERR

0.13 %

OERR

LOAD

1

∆VO 1,000 h 40 ppm

20 ppm

O_HYS

2.9985 3.000 3.0015 V

2.996 3.000 3.004 V

1.5 mV

0.05 %
4 mV

I

LOAD

LOAD

= 0 mA to 10 mA, VIN = 6 V

= −10 mA to 0 mA, VIN = 6 V

nV√

Hz

Rev. B | Page 5 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

ADR434 ELECTRICAL CHARACTERISTICS

VIN = 6.1 V to 18 V, I

Table 5.

Parameter Symbol Conditions Min Typ Max Unit

Output Voltage

B Grade VO 4.0945 4.096 4.0975 V
A Grade VO 4.091 4.096 4.101 V

Initial Accuracy

B Grade V
B Grade V
A Grade V
A Grade V

Temperature Coefficient TCVO

SOIC-8 (B Grade) −40°C < TA < +125°C 1 3 ppm/°C
SOIC-8 (A Grade) −40°C < TA < +125°C 2 10 ppm/°C
MSOP-8 −40°C < TA < +125°C 2 10 ppm/°C

Line Regulation ∆VO/∆VIN VIN = 6.1 V to 18 V

−40°C < TA < +125°C 5 20 ppm/V
Load Regulation ∆VO/∆I

−40°C < TA < +125°C 15 ppm/mA
I

−40°C < TA < +125°C 15 ppm/mA
Quiescent Current IIN No load, −40°C < TA < +125°C 595 800 µA
Voltage Noise eN p-p 0.1 Hz to 10.0 Hz 6.25 µV p-p
Voltage Noise Density eN 1 kHz 100
Turn-On Settling Time tR CIN = 0 10 µs
Long-Term Stability1 ∆VO 1,000 h 40 ppm
Output Voltage Hysteresis V
Ripple Rejection Ratio RRR fIN = 10 kHz −70 dB
Short Circuit to GND ISC 40 mA
Supply Voltage Operating Range VIN 6.1 18 V
Supply Voltage Headroom VIN − VO 2 V

1

The long-term stability specification is noncumulative. The drift in subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.

= 0 mA, TA = 25°C, unless otherwise noted.

LOAD

1.5 mV

OERR

0.04 %

OERR

5 mV

OERR

0.13 %

OERR

I

LOAD

20 ppm

O_HYS

= 0 mA to 10 mA, VIN = 7 V

LOAD

= −10 mA to 0 mA, VIN = 7 V

LOAD

nV√

Hz

Rev. B | Page 6 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

ADR435 ELECTRICAL CHARACTERISTICS

VIN = 7 V to 18 V, I

Table 6.

Parameter Symbol Conditions Min Typ Max Unit

Output Voltage

B Grade VO 4.998 5.000 5.002 V
A Grade VO 4.994 5.000 5.006 V

Initial Accuracy

B Grade V
B Grade V
A Grade V
A Grade V

Temperature Coefficient TCV

SOIC-8 (B Grade) −40°C < TA < +125°C 1 3 ppm/°C
SOIC-8 (A Grade) −40°C < TA < +125°C 2 10 ppm/°C
MSOP-8 −40°C < TA < +125°C 2 10 ppm/°C

Line Regulation ∆VO/∆VIN VIN = 7 V to 18 V

−40°C < TA < +125°C 5 20 ppm/V
Load Regulation ∆VO/∆I

−40°C < TA < +125°C 15 ppm/mA
I

−40°C < TA < +125°C 15 ppm/mA
Quiescent Current IIN No load, −40°C < TA < +125°C 620 800 µA
Voltage Noise eN p-p 0.1 Hz to 10 Hz 8 µV p-p
Voltage Noise Density eN 1 kHz 115
Turn-On Settling Time tR CIN = 0 10 µs
Long-Term Stability1 ∆VO 1,000 h 40 ppm
Output Voltage Hysteresis V
Ripple Rejection Ratio RRR fIN = 10 kHz −70 dB
Short Circuit to GND ISC 40 mA
Supply Voltage Operating Range VIN 7 18 V
Supply Voltage Headroom VIN − VO 2 V

1

The long-term stability specification is noncumulative. The drift in subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.

= 0 mA, TA = 25°C, unless otherwise noted.

LOAD

2 mV

OERR

0.04 %

OERR

6 mV

OERR

0.12 %

OERR

O

LOAD

20 ppm

O_HYS

I

= 0 mA to 10 mA, VIN = 8 V

LOAD

= −10 mA to 0 mA, VIN = 8 V

LOAD

nV/√

Hz

Rev. B | Page 7 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

ADR439 ELECTRICAL CHARACTERISTICS

VIN = 6.5 V to 18 V, I

Table 7.

Parameter Symbol Conditions Min Typ Max Unit

Output Voltage

B Grade VO 4.498 4.500 4.502 V
A Grade VO 4.4946 4.500 4.5054 V

Initial Accuracy

B Grade V
B Grade V
A Grade V
A Grade V

Temperature Coefficient TCVO

SOIC-8 (B Grade) −40°C < TA < +125°C 1 3 ppm/°C
SOIC-8 (A Grade) −40°C < TA < +125°C 2 10 ppm/°C
MSOP-8 −40°C < TA < +125°C 2 10 ppm/°C

Line Regulation ∆VO/∆VIN VIN = 6.5 V to 18 V

−40°C < TA < +125°C 5 20 ppm/V
Load Regulation ∆VO/∆I

−40°C < TA < +125°C 15 ppm/mA
I

−40°C < TA < +125°C 15 ppm/mA
Quiescent Current IIN No load, −40°C < TA < +125°C 600 800 µA
Voltage Noise eN p-p 0.1 Hz to 10.0 Hz 7.5 µV p-p
Voltage Noise Density eN 1 kHz 110
Turn-On Settling Time tR CIN = 0 10 µs
Long-Term Stability1 ∆VO 1,000 h 40 ppm
Output Voltage Hysteresis V
Ripple Rejection Ratio RRR fIN = 10 kHz −70 dB
Short Circuit to GND ISC 40 mA
Supply Voltage Operating Range VIN 6.5 18 V
Supply Voltage Headroom VIN − VO 2 V

1

The long-term stability specification is noncumulative. The drift in subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.

= 0 mV, TA = 25°C, unless otherwise noted.

LOAD

2 mV

OERR

0.04 %

OERR

5.4 mV

OERR

0.12 %

OERR

I

LOAD

20 ppm

O_HYS

= 0 mA to 10 mA, VIN = 6.5 V

LOAD

= −10 mA to 0 mA, VIN = 6.5 V

LOAD

nV/√

Hz

Rev. B | Page 8 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

ABSOLUTE MAXIMUM RATINGS

@ 25°C, unless otherwise noted.

Table 8.

Parameter Rating

Supply Voltage 20 V
Output Short-Circuit Duration to GND Indefinite
Storage Temperature Range (R, RM Packages) −65°C to +125°C
Operating Temperature Range −40°C to +125°C
Junction Temperature Range −65°C to +150°C
Lead Temperature Range (Soldering, 60 s) 300°C

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.

PACK AGE TYPE

Table 9.

Package Type

8-Lead SOIC (R) 130 43 °C/W
8-Lead MSOP (RM) 190 °C/W

1

θJA is specified for worst-case conditions (device soldered in circuit board for

surface-mount packages).

1

θ

JA

θJC Unit

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

2.5007

2.5005

2.5003

2.5001

OUTPUT VOLTAGE (V)

2.4999

2.4997

2.4995
–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

Figure 3. ADR431 V

vs. Temperature

OUT

4.0980

4.0975

4.0970

4.0965

4.0960

OUTPUT VOLTAGE (V)

4.0955

04500-0-015

0.7

0.6

0.5

SUPPLY CURRENT (mA)

0.4

0.3

700

650

600

550

500

SUPPLY CURRENT (µA)

450

+125°C

+25°C

–40°C

8104 6 12 14 16

INPUT VOLTAGE (V)

Figure 6. ADR435 Supply Current vs. Input Voltage

04500-0-018

4.0950
–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

Figure 4. ADR434 V

vs. Temperature

OUT

5.0025

5.0020

5.0015

5.0010

5.0005

5.0000

OUTPUT VOLTAGE (V)

4.9995

4.9990
–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

Figure 5. ADR435 V

vs. Temperature

OUT

04500-0-016

04500-0-017

Rev. B | Page 10 of 24

400

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

Figure 7. ADR435 Supply Current vs. Temperature

0.60

0.58

0.56

0.54

0.52

0.50

0.48

0.46

SUPPLY CURRENT (mA)

0.44

0.42

0.40
10 126 8 14 16 18

INPUT VOLTAGE (V)

+125°C

+25°C

–40°C

Figure 8. ADR431 Supply Current vs. Input Voltage

04500-0-019

04500-0-020

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

610

2.5

580

550

520

490

460

SUPPLY CURRENT (µA)

430

400

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

Figure 9. ADR431 Supply Current vs. Temperature

15

12

9

6

LOAD REGULATION (ppm/mA)

3

0

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

IL= 0mA to 10mA

Figure 10. ADR431 Load Regulation vs. Temperature

15

IL= 0mA to 10mA

04500-0-021

04500-0-022

2.0

–40°C

1.5
+25°C

1.0

+125°C

DIFFERENTIAL VOLTAGE (V)

0.5

0

–5–10 0 5 10

LOAD CURRENT (mA)

Figure 12. ADR431 Minimum Input/Output

Differential Voltage vs. Load Current

1.9

1.8

1.7

1.6

1.5

1.4

1.3

MINIMUM HEADROOM (V)

1.2

1.1

1.0

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

NO LOAD

Figure 13. ADR431 Minimum Headroom vs. Temperature

2.5

04500-0-024

04500-0-025

12

9

6

LOAD REGULATION (ppm/mA)

3

0

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

Figure 11. ADR435 Load Regulation vs. Temperature

04500-0-023

Rev. B | Page 11 of 24

2.0

1.5

1.0

DIFFERENTIAL VOLTAGE (V)

0.5

0

+125°C

–5–10 0 5 10

Figure 14. ADR435 Minimum Input/Output

Differential Voltage vs. Load Current

–40°C

+25°C

LOAD CURRENT (mA)

04500-0-026

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

1.9

1.7

1.5

1.3

MINIMUM HEADROOM (V)

1.1

0.9
–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

NO LOAD

04500-0-027

C

= 0.01µF

LOAD

NOINPUT CAPACITOR

V

= 1V/DIV

OUT

VIN = 2V/DIV

TIME = 4µs/DIV

04500-0-031

Figure 15. ADR435 Minimum Headroom vs. Temperature

20

16

12

8

4

LINE REGULATION (ppm/V)

0

–4

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (°C)

VIN= 7V TO 18V

Figure 16. ADR435 Line Regulation vs. Temperature

CIN = 0.01µF
NO LOAD

V

OUT

= 1V/DIV

04500-0-028

Figure 18. ADR431 Turn-On Response, 0.01 µF Load Capacitor

CIN = 0.01µF

V

= 1V/DIV

OUT

VIN = 2V/DIV

NO LOAD

TIME = 4µs/DIV

Figure 19. ADR431 Turn-Off Response

BYPASS CAPACITOR = 0µF

V

IN

LINE
INTERRUPTION

500mV/DIV

04500-0-032

VIN = 2V/DIV

TIME = 4µs/DIV

Figure 17. ADR431 Turn-On Response

04500-0-030

Rev. B | Page 12 of 24

V

= 50mV/DIV

OUT

TIME = 100µs/DIV

Figure 20. ADR431 Line Transient Response—No Capacitors

04500-0-033

BYPASS CAPACITOR = 0.1µF

V

IN

V

= 50mV/DIV

OUT

LINE
INTERRUPTION

500mV/DIV

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

2µV/DIV

TIME = 100µs/DIV

04500-0-034

Figure 21. ADR431 Line Transient Response—0.1 µF Bypass Capacitor

1µV/DIV

TIME = 1s/DIV

04500-0-035

Figure 22. ADR431 0.1 Hz to 10.0 Hz Voltage Noise

Figure 24. ADR435 0.1 Hz to 10.0 Hz Voltage Noise

50µV/DIV

Figure 25. ADR435 10 Hz to 10 kHz Voltage Noise

14

12

TIME = 1s/DIV

TIME = 1s/DIV

04500-0-037

04500-0-038

50µV/DIV

TIME = 1s/DIV

Figure 23. ADR431 10 Hz to 10 kHz Voltage Noise

04500-0-036

Rev. B | Page 13 of 24

10

8

6

NUMBER OF PARTS

4

2

0
–120 –90 –70 –50 –30 –10 10 30 50 70 90 120

DEVIATION (PPM)

Figure 26. ADR431 Typical Hysteresis

04500-0-029

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

50

45

40

35

30

25

20

15

OUTPUT IMPEDANCE (Ω)

10

5

0

100 10k1k 100k

FREQUENCY (Hz)

ADR435

3

4

3

R

D

A

ADR430

04500-0-039

10

–10

–30

–50

–70

–90

RIPPLE REJECTION (dB)

–110

–130

–150

10 100 1k 10k 100k 1M

FREQUENCY (Hz)

04500-0-040

Figure 27. Output Impedance vs. Frequency

Figure 28. Ripple Rejection Ratio

Rev. B | Page 14 of 24

(

)

+θ×

=

V

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 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.

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.

TPT

DJ

(2)

AJA

where:

T

and TA are the junction and ambient temperatures,

J

respectively.

P

is the device power dissipation.

D

is the device package thermal resistance.

θ

JA

BASIC VOLTAGE REFERENCE CONNECTIONS

Voltage references, in general, require a bypass capacitor
connected from V
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.

to GND. The circuit in Figure 30

OUT

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

OUT

P

IR1VΔGV ×−×= (1)

PTAT

where:
G is the gain of the reciprocal of the divider ratio.
∆V

is the difference in pinch-off voltage between the two JFETs.

P

I

is the positive temperature coefficient correction current.

PTAT

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

R2

R3

GND

V

IN

OUT

04500-0-002

I

I

PTAT

1

**

*EXTRA CHANNEL IMPLANT
V

= G(∆V

OUT

Figure 29. Simplified Schematic Device

Power Dissipation Considerations

I

1

–R1×I

P

ADR43x

∆

V

P

R1

)

PTAT

1

TP

IN

+

10µF

0.1µF

Figure 30. Basic Voltage Reference Configuration

2

ADR43x

TOP VIEW

3

NIC

(Not to Scale)

4

NIC = NO INTERNAL CONNECTION
TP = TEST PIN (DO NOT CONNECT)

8
7

6

5

TP
NIC

OUTPUT

TRIM

0.1µF

04500-0-003

NOISE PERFORMANCE

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.

TURN-ON TIME

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 compo­nents 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.

Rev. B | Page 15 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

APPLICATIONS

OUTPUT ADJUSTMENT

The ADR43x trim terminal can be used to adjust the output
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 perform­ance 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.

INPUT

LASER BEAM

ACTIVATOR

CONTROL

ELECTRONICS

SOURCE FIBER

GIMBAL + SENSOR

LEFT

AMPL

DAC

MEMS MIRROR

PREAMP

ADC

AMPL

DAC

DESTINATION
FIBER

ACTIVATOR
RIGHT

ADR431

ADR431

ADR431

V

IN

V

O

ADR43x

TRIM

GND

Figure 31. Output Trim Adjustment

470kΩ

R1

OUTPUT

R

P

10kΩ
10kΩ (ADR420)

R2

15kΩ (ADR421)

VO = ±0.5%

04500-0-004

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 informa­tion 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.

DSP

GND

Figure 32. All-Optical Router Network

NEGATIVE PRECISION REFERENCE WITHOUT PRECISION RESISTORS

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 current­switching 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 opera­tional 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.

A negative reference can easily be generated by adding a
precision op amp and configuring it as shown in Figure 33.

is at virtual ground and, therefore, the negative reference

V

OUT

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.

04500-0-005

Rev. B | Page 16 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

+V

DD

2

V

IN

V

6

OUT

ADR43x

GND

4

A1

–

V

DD

A1 = OP777, OP193

–

V

REF

04500-0-006

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

S

SST111
VISHAY

V

IN

ADR43x

V

OUT

GND

OP90

Figure 34. High Voltage Floating Current Source

2N3904

R

2.1kΩ

–V

S

L

04500-0-007

KELVIN CONNECTIONS

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 (V
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.

= R × IL) at the load. However, the Kelvin

ERROR

V

IN

2

ADR43x

V

OUT

GND

4

6

R

LW

V

IN

A1

+

A1 = OP191

V

OUT

SENSE

R

LW

V

OUT

FORCE
R

L

04500-0-008

Figure 35. Advantage of Kelvin Connection

DUAL POLARITY REFERENCES

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.

V

IN

1µF 0.1µF

Figure 36. +5 V and −5 V References Using ADR435

+10V

Figure 37. +2.5 V and −2.5 V References Using ADR435

GND

2

V

IN

ADR435

GND

4

2

V

IN

ADR435

U1

4

V

OUT

U1

TRIM

V

OUT

TRIM

6

5

6

5

5.6kΩ

5.6kΩ

10k

5k

+2.5V

R1

R2

–2.5V

R1

Ω

R3

Ω

+10V

V+

OP1177

U2

V–

–

10V

V+

OP1177

U2

V–

–10V

10k

+5V

R2

Ω

–5V

04500-0-009

04500-0-010

Rev. B | Page 17 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

PROGRAMMABLE CURRENT SOURCE

Together with a digital potentiometer and a Howland current
pump, ADR435 forms the reference source for a programmable
current as

RR2

+

2

⎛
⎜

⎜

I ×

=

L

⎜
⎜
⎝

and

A

⎞

B

⎟

R1

⎟

V

(3)

R

2

B

W

⎟
⎟
⎠

PROGRAMMABLE DAC REFERENCE VOLTAGE

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 V
rest of the DACs. The circuit configuration is shown in Figure 39.

V

REFA

DAC A

V

OUTA

R1 ± 0.1%

V

IN

R2
± 0.1%

ADR436

for the

REFX

V

REF

D

V ×=

W

V

(4)

REF

N

2

where:

D is the decimal equivalent of the input code.
N is the number of bits.

In addition,
respectively. R2

′

and must be equal to R1 and R21R
in theory can be made as small as needed to

B

′

2R

+ R2B,

A

achieve the necessary current within the A2 output current
driving capability. In this example, OP2177 can deliver a maxi­mum 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 V

and VB of the digital potentiometer are supplied

A

with the dual polarity references, as shown previously.

C1

10pF

V

DD

2

V

IN

ADR435

U1

GND

4

TRIM

V

OUT

R1'

50kΩ

5

AD5232

U2

DIGITAL

POTENTIOMETER

6

A

U2

W

B

V

DD

V+

OP2177

A1

V–

V

SS

C2

10pF

R1

50kΩ

Figure 38. Programmable Current Source

R2'

1kΩ

V

DD

V+

OP2177

A2

V–

V

SS

+

VL

–

R2
1kΩ

R2

B

10Ω

A

LOAD

GND

IL

V

REFB

DAC B

V

REFC

DAC C

V

REFD

DAC D

AD7398

V

V

V

OUTB

OUTC

OUTD

VOB=V

REFX(DB

V

OC=VREFX(DC

V

OD=VREFX(DD

)

)

)

04500-0-012

Figure 39. Programmable DAC Reference

The relationship of V

REFX

to V

depends on the digital code

REF

and the ratio of R1 and R2, and is given by

R2

⎞

⎛

1

V

REFX

V

=

⎛
⎜
⎝

REF

1

+×

⎟

⎜

R1

⎠

⎝

N

2

(5)

R2D

⎞

×+

⎟

R1

⎠

where:

D is the decimal equivalent of input code.
N is the number of bits.

is the applied external reference.

V

REF

V

is the reference voltage for DAC A to DAC D.

REFX

Table 10. V

04500-0-011

R1, R2 Digital Code V

R1 = R2 0000 0000 0000 2 V
R1 = R2 1000 0000 0000 1.3 V
R1 = R2 1111 1111 1111 V
R1 = 3R2 0000 0000 0000 4 V
R1 = 3R2 1000 0000 0000 1.6 V
R1 = 3R2 1111 1111 1111 V

vs. R1 and R2

REFX

REF

REF

REF

REF

REF

REF

REF

Rev. B | Page 18 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

PRECISION VOLTAGE REFERENCE FOR DATA CONVERTERS

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
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.

+5V

ANALOG

SUPPLY

0.1µF

10µF

V

IN

V

OUT

ADR431

GND

0.1µF

10µF

RANGES

SELECT

CALIBRATE

ANALOG

INPUT

ANALOG

GROUND

–5V

ANALOG

SUPPLY

0.1µF

0.1µF

Figure 40. Voltage Reference for 16-Bit ADC AD7701

and low frequency signals

AD7701

AV

DD

V

REF

BP/UP

CAL

A

IN

AGND

AV

SS

DV

SLEEP

MODE
DRDV

CS

SCLK

SDATA

CLKIN

CLKOUT

SC1
SC2

DGND

DV

DD

SS

0.1µF

DATA READY

READ (TRANSMIT)
SERIAL CLOCK
SERIAL CLOCK

0.1µF

04500-0-013

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 V
N1. Therefore, the load current is furnished by VIN. In this
configuration, a 50 mA load is achievable at 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.

V

IN

to be equal to V

O

2

U1

V

IN

6

V

OUT

5

TRIM

GND

4

ADR431

by regulating the turn on of

REF

N1

5V

2N7002

+

V+

AD8601

V–

–

U2

Figure 41. Precision Boosted Output Regulator

of 5 V.

IN

V

R

L

O

25Ω

04500-0-014

Rev. B | Page 19 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

Y

OUTLINE DIMENSIONS

3.00
BSC

85

3.00

BSC

PIN 1

0.65 BSC

0.15

0.00

0.38

0.22

COPLANARITY

0.10
COMPLIANT TO JEDEC STANDARDS MO-187AA

4

SEATING
PLANE

4.90
BSC

1.10 MAX

0.23

0.08

8°
0°

0.80

0.60

0.40

Figure 42. 8-Lead Mini Small Outline Package [MSOP]

(RM-8)

Dimensions shown in millimeters

5.00 (0.1968)

4.80 (0.1890)

4.00 (0.1574)

3.80 (0.1497)

0.25 (0.0098)

0.10 (0.0040)

COPLANARIT

0.10

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

85

1.27 (0.0500)

SEATING

PLANE

COMPLIANT TO JEDEC STANDARDS MS-012AA

BSC

6.20 (0.2440)

5.80 (0.2284)

41

1.75 (0.0688)

1.35 (0.0532)

0.51 (0.0201)

0.31 (0.0122)

0.25 (0.0098)

0.17 (0.0067)

0.50 (0.0196)

0.25 (0.0099)

8°

1.27 (0.0500)

0°

0.40 (0.0157)

× 45°

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

Output

Model

ADR430AR 2.048 3 0.15 10 8-lead SOIC N/A –40°C to +125°C
ADR430AR-REEL7 2.048 3 0.15 10 8-Lead SOIC 3,000 –40°C to +125°C
ADR430ARM 2.048 3 0.15 10 8-Lead MSOP N/A RHA –40°C to +125°C
ADR430ARM-REEL7 2.048 3 0.15 10 8-Lead MSOP 1,000 RHA –40°C to +125°C
ADR430BR 2.048 1 0.05 3 8-lead SOIC N/A –40°C to +125°C
ADR430BR-REEL7 2.048 1 0.05 3 8-Lead SOIC 3,000 –40°C to +125°C
ADR431AR 2.500 3 0.12 10 8-Lead SOIC N/A –40°C to +125°C
ADR431AR-REEL7 2.500 3 0.12 10 8-Lead SOIC 3,000 –40°C to +125°C
ADR431ARM 2.500 3 0.12 10 8-Lead MSOP N/A RJA –40°C to +125°C
ADR431ARM-REEL7 2.500 3 0.12 10 8-Lead MSOP 1,000 RJA –40°C to +125°C
ADR431BR 2.500 1 0.04 3 8-Lead SOIC N/A –40°C to +125°C
ADR431BR-REEL7 2.500 1 0.04 3 8-Lead SOIC 3,000 –40°C to +125°C
ADR433AR 3.000 4 0.12 10 8-Lead SOIC N/A –40°C to +125°C
ADR433AR-REEL7 3.000 4 0.12 10 8-Lead SOIC 3,000 –40°C to +125°C
ADR433ARM 3.000 4 0.12 10 8-Lead MSOP N/A RKA –40°C to +125°C
ADR433ARM-REEL7 3.000 4 0.12 10 8-Lead MSOP 1,000 RKA –40°C to +125°C
ADR433BR 3.000 1.5 0.05 3 8-Lead SOIC N/A –40°C to +125°C
ADR433BR-REEL7 3.000 1.5 0.05 3 8-Lead SOIC 3,000 –40°C to +125°C
ADR434AR 4.096 5 0.13 10 8-Lead SOIC N/A –40°C to +125°C
ADR434AR-REEL7 4.096 5 0.13 10 8-Lead SOIC 3,000 –40°C to +125°C
ADR434ARM 4.096 5 0.13 10 8-Lead MSOP N/A RLA –40°C to +125°C
ADR434ARM-REEL7 4.096 5 0.13 10 8-Lead MSOP 1,000 RLA –40°C to +125°C
ADR434BR 4.096 1.5 0.04 3 8-Lead SOIC N/A –40°C to +125°C
ADR434BR-REEL7 4.096 1.5 0.04 3 8-Lead SOIC 3,000 –40°C to +125°C
ADR435AR 5.000 6 0.12 10 8-Lead SOIC N/A –40°C to +125°C
ADR435AR-REEL7 5.000 6 0.12 10 8-Lead SOIC 3,000 –40°C to +125°C
ADR435ARM 5.000 6 0.12 10 8-Lead MSOP N/A RMA –40°C to +125°C
ADR435ARM-REEL7 5.000 6 0.12 10 8-Lead MSOP 1,000 RMA –40°C to +125°C
ADR435BR 5.000 2 0.04 3 8-Lead SOIC N/A –40°C to +125°C
ADR435BR-REEL7 5.000 2 0.04 3 8-Lead SOIC 3,000 –40°C to +125°C
ADR439AR 4.500 5.4 0.12 10 8-Lead SOIC N/A –40°C to +125°C
ADR439AR-REEL7 4.500 5.4 0.12 10 8-Lead SOIC 3,000 –40°C to +125°C
ADR439ARM 4.500 5.4 0.12 10 8-Lead MSOP N/A RNA –40°C to +125°C
ADR439ARM-REEL7 4.500 5.4 0.12 10 8-Lead MSOP 1,000 RNA –40°C to +125°C
ADR439BR 4.500 2 0.04 3 8-Lead SOIC N/A –40°C to +125°C
ADR439BR-REEL7 4.500 2 0.04 3 8-Lead SOIC 3,000 –40°C to +125°C

Voltage (V

Accuracy

)

O

mV (%)

Temperature
Coefficient
Package
(ppm/°C)

Package
Description

Parts
per Reel

Branding

Temperature
Range

Rev. B | Page 21 of 24

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

NOTES

Rev. B | Page 22 of 24

NOTES

ADR430/ADR431/ADR433/ADR434/ADR435/ADR439

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