AD581SH883B [ADI]
High Precision 10 V IC Reference; 高精度10 V IC基准
| 型号： | AD581SH883B |
| 厂家： | 
ADI |
| 描述： | High Precision 10 V IC Reference |
| 文件： | 总12页 (文件大小：329K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
High Precision
10 V IC Reference
AD581
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Laser trimmed to high accuracy
10.000 V ±± mV (L and U models)
Trimmed temperature coefficient
± ppm/°C maximum, 0°C to 70°C (L model)
10 ppm/°C maximum, −±±°C to +12±°C (U model)
Excellent long-term stability
+V
S
V
OUT
AD581
2± ppm/1000 hrs (noncumulative)
−10 V reference capability
Low quiescent current: 1.0 mA maximum
10 mA current output capability
3-pin TO-± package
GND
TO-5
BOTTOM VIEW
Figure 1.
MIL-STD-883 compliant versions available
GENERAL DESCRIPTION
The AD581J, AD581K, and AD581L are specified for operation
from 0°C to 70°C; the AD581S, AD581T, and AD581U are
specified for the −55°C to +125°C range. All grades are
packaged in a hermetically sealed 3-pin TO-5 metal can.
The AD581 is a 3-pin, temperature compensated, monolithic,
band gap voltage reference that provides a precise 10.00 V output
from an unregulated input level ranging from 12 V to 30 V.
Laser wafer trimming (LWT) is used to trim both the initial
error at +25°C as well as the temperature coefficient, resulting
in high precision performance previously available only in expen-
sive hybrids or oven regulated modules. The 5 mV initial error
tolerance and 5 ppm/°C guaranteed temperature coefficient of
the AD581L is available in a monolithic voltage reference.
PRODUCT HIGHLIGHTS
1. Laser trimming of both initial accuracy and temperature
coefficient results in very low errors over temperature
without the use of external components. The AD581L has
a maximum deviation from 10.000 V of 7.25 mV from
0°C to 70°C, whereas the AD581U guarantees 15 mV
maximum total error without external trims from −55°C
to +125°C.
2. Because the laser trimming is done on the wafer prior to
separation into individual chips, the AD581 is extremely
valuable to hybrid designers for its ease of use, lack of
required external trims, and inherent high performance.
3. The AD581 can also be operated in a 2-pin Zener mode to
provide a precision −10 V reference with just one external
resistor to the unregulated supply. The performance in this
mode is nearly equal to that of the standard 3-pin confi-
guration.
4. Advanced circuit design using the band gap concept allows
the AD581 to give full performance with an unregulated
input voltage down to 13 V. With an external resistor, the
device operates with a supply as low as 11.4 V.
5. The AD581 is available in versions compliant with
MILSTD-883. Refer to the military datasheet for detailed
specifications.
The band gap circuit design used in the AD581 offers several
advantages over classical Zener breakdown diode techniques.
Most important, no external components are required to
achieve full accuracy and significant stability to low power
systems. In addition, total supply current to the device,
including the output buffer amplifier (which can supply up
to 10 mA) is typically 750 μA. The long-term stability of the
band gap design is equivalent to selected Zener reference
diodes.
The AD581 is recommended for use as a reference for 8-, 10-
or 12-bit digital-to-analog converters (DACs) that require an
external precision reference. The device is also ideal for all types
of analog-to-digital converters (ADCs) up to 14-bit accuracy,
either successive approximation or integrating designs, and can
generally offer better performance than that provided by standard
self-contained references.
Rev. C
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 registeredtrademarks are theproperty of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
©2009 Analog Devices, Inc. All rights reserved.
AD581
TABLE OF CONTENTS
Features .............................................................................................. 1
Output Current Characteristics...................................................7
Dynamic Performance..................................................................7
Precision High Current Supply ...................................................8
Connection for Reduced Primary Supply..................................8
The AD581 as a Current Limiter.....................................................9
Negative 10 V Reference...............................................................9
10 V Reference with Multiplying CMOS DACs or ADCs .......9
Precision 12-Bit DAC Reference .................................................9
Outline Dimensions........................................................................11
Ordering Guide ...........................................................................11
Functional Block Diagram .............................................................. 1
General Description......................................................................... 1
Product Highlights ........................................................................... 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 5
ESD Caution.................................................................................. 5
Applying the AD581......................................................................... 6
Voltage Variation vs. Temperature ............................................. 6
REVISION HISTORY
4/09—Rev. B to Rev. C
Updated Format..................................................................Universal
Changes to Table 1............................................................................ 3
Changes to Figure 2.......................................................................... 6
Changes to Figure 11........................................................................ 8
Changes to 10 V Reference with Multiplying CMOS DACs
or ADCs Section ............................................................................... 9
Changes to Precision 12-Bit DAC Reference Section.................. 9
Changes to Figure 13........................................................................ 9
Changes to Figure 15 and Figure 16............................................. 10
Updated Outline Dimensions....................................................... 11
Changes to Ordering Guide .......................................................... 11
Rev. C | Page 2 of 12
AD581
SPECIFICATIONS
@ VIN = +15 V and TA = +25°C.
Specifications shown in boldface are tested on all production units at final electrical test. Results from those tests are used to calculate
outgoing quality levels. All minimum and maximum specifications are guaranteed, although only those shown in boldface are tested on
all production units.
Table 1.
AD±81J
Min Typ
AD±81K
Min Typ
AD±81L
Min Typ
Model
Max
±30
±13.±
30
Max
±10
±6.7±
15
Max
±±
Units
mV
OUTPUT VOLTAGE TOLERANCE
(Error from Nominal 10,000 V Output)
OUTPUT VOLTAGE CHANGE
Maximum Deviation from +25°C
Value, TMIN to TMAX
mV
±2.2±
5
Temperature Coefficient
LINE REGULATION
ppm/°C
15 V ≤ VIN ≤ 30 V
mV
3.0
3.0
3.0
(0.002)
1.0
(0.005)
(0.002)
1.0
(0.005)
(0.002) %/V
mV
(0.005) %/V
13 V ≤ VIN ≤ 15 V
1.0
LOAD REGULATION
0 ≤ IOUT ≤ 5 mA
200
0.75
200
40
200
0.75
200
40
200
0.75
200
40
μV/mA
±00
1.0
±00
1.0
±00
1.0
QUIESCENT CURRENT
TURN-ON SETTLING TIME TO 0.1%1
NOISE (0.1 Hz TO 10 Hz)
LONG-TERM STABILITY
SHORT-CIRCUIT CURRENT
OUTPUT CURRENT
Source @ +25°C
mA
μs
μV (p-p)
ppm/1000 hr
mA
25
25
25
30
30
30
10
5
5
10
5
5
10
5
5
mA
mA
μA
Source TMIN to TMAX
Sink TMIN to TMAX
TEMPERATURE RANGE
Specified
0
70
0
70
0
70
°C
°C
Operating
−65
+150
−65
+150
−65
+150
PACKAGE OPTION2
TO-5 (H-03B)
AD581JH
AD581KH
AD581LH
1 See Figure 7.
2 H indicates the hermetic metal can.
Rev. C | Page 3 of 12
AD581
Table 2.
AD±81S
Min Typ
AD±81T
Min Typ
AD±81U
Min Typ
Model
Max
±30
±30
30
Max
±10
±1±
15
Max
±±
Units
mV
OUTPUT VOLTAGE TOLERANCE
(Error from Nominal 10,000 V Output)
OUTPUT VOLTAGE CHANGE
Maximum Deviation from +25°C
Value, TMIN to TMAX
mV
±10
10
Temperature Coefficient
LINE REGULATION
ppm/°C
15 V ≤ VIN ≤ 30 V
mV
3.0
3.0
3.0
(0.002)
1.0
(0.005)
(0.002)
1.0
(0.005)
(0.002) %/V
mV
(0.005) %/V
13 V ≤ VIN ≤ 15 V
1.0
LOAD REGULATION
0 ≤ IOUT ≤ 5 mA
200
0.75
200
40
200
0.75
200
40
200
0.75
200
40
μV/mA
±00
1.0
±00
1.0
±00
1.0
QUIESCENT CURRENT
TURN-ON SETTLING TIME TO 0.1%1
NOISE (0.1 Hz TO 10 Hz)
LONG-TERM STABILITY
SHORT-CIRCUIT CURRENT
OUTPUT CURRENT
Source @ +25°C
Source TMIN to TMAX
Sink TMIN to TMAX
Sink −55°C to +85°C
TEMPERATURE RANGE
Specified
mA
μs
μV (p-p)
ppm/1000 hr
mA
25
25
25
30
30
30
10
5
200
5
10
5
200
5
10
5
200
5
mA
mA
μA
mA
−55
−65
+125
+150
−55
−65
+125
+150
−55
−65
+125
+150
°C
°C
Operating
PACKAGE OPTION2
TO-5 (H-03B)
AD581SH
AD581TH
AD581UH
1 See Figure 7.
2 H indicates hermetic metal can.
Rev. C | Page 4 of 12
AD581
ABSOLUTE MAXIMUM RATINGS
Table 3.
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 above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Parameter
Rating
Input Voltage
40 V
Power Dissipation @ +25°C
Operating Junction Temperature Range
Lead Temperature (Soldering 10 sec)
Thermal Resistance
600 mW
−55°C to +150°C
+300°C
Junction-to-Ambient
150°C/W
ESD CAUTION
Rev. C | Page 5 of 12
AD581
APPLYING THE AD581
V+
The AD581 is easy to use in virtually all precision reference
applications. The three pins are simply: primary supply, ground,
and output, with the case grounded. No external components
are required even for high precision applications; the degree of
desired absolute accuracy is achieved simply by selecting the
required device grade. The AD581 requires less than 1 mA quies-
cent current from an operating supply range of 13 V to 30 V.
13V TO 30V
R40
R41
Q7
Q20
Q8
Q15
Q10
Q11
C52
Q6
R42
Q12
C51
10V
Q14
R34
R37
Q16
Q13
Q5
C50
+V
S
R33
R32
R35
R36
V
OUT
10V
AD581
Q3
Q4
GND
Q2
Q1
R30
R39
R31
Figure 2. Pin Configuration (Bottom View)
V–
An external fine trim may be desired to set the output level to
exactly 10.000 V within less than a millivolt (calibrated to a
main system reference). System calibration may also require a
reference slightly different from 10.00 V. In either case, the
optional trim circuit shown in Figure 3 can offset the output by
up to 30 mV (with the 22 Ω resistor), if needed, with minimal
effect on other device characteristics.
Figure 4. Simplified Schematic
VOLTAGE VARIATION vs. TEMPERATURE
Some confusion exists in the area of defining and specifying
reference voltage error over temperature. Historically, references
have been characterized using a maximum deviation per degree
Celsius; that is, 10 ppm/°C. However, because of nonlinearities
in temperature characteristics, which originated in standard
Zener references (such as S-type characteristics) manufacturers
opt for the maximum limit error band approach to specify devices.
This technique involves measurement of the output at three,
five, or more different temperatures to guarantee that the output
voltage falls within the given error band. The temperature charac-
teristic of the AD581 consistently follows the S-curve shown in
Figure 5. Three-point measurement of each device guarantees
the error band over the specified temperature range.
10.005
+15V
TRIM
RANGE
MAX
Δ TCR
R
22Ω
12Ω
3.9Ω
±30mV
±10mV
±5mV
3.5ppm/°C
2.0ppm/°C
0.6ppm/°C
+V
S
V
OUT
+10V
AD581
6.8kΩ
GND
R
10kΩ
–15V
4.3kΩ
Figure 3. Optional Fine Trim Configuration
10.000
9.995
–55 –50 –40 –30 –20 –10
0
10 20 30 40 50 60 70 80 90 100 110 120 125
TEMPERATURE (°C)
Figure 5. Typical Temperature Characteristic
Rev. C | Page 6 of 12
AD581
12V
11V
The error band which is guaranteed with the AD581 is the
maximum deviation from the initial value at +25°C; this error
band is of more use to a designer than one which simply guarantees
the maximum total change over the entire range (that is, in the
latter definition, all of the changes could occur in the positive
direction). Thus, with a given grade of the AD581, the designer
can easily determine the maximum total error from initial toler-
ance plus temperature variation (for example, for the AD581T, the
initial tolerance is 10 mV, the temperature error band is 15 mV,
thus the unit is guaranteed to be 10.000 V 25 mV from −55°C
to +125°C).
10.03V
10.02V
10.01V
10.00V
10V
20V
10V
0V
0
50 100 150 200 250
SETTLING TIME (µs)
Figure 7. Output Settling Characteristic
OUTPUT CURRENT CHARACTERISTICS
The AD581 has the capability to either source or sink current
and provide good load regulation in either direction, although
it has better characteristics in the source mode (positive current
into the load). The circuit is protected for shorts to either positive
supply or ground. The output voltage vs. output current charac-
teristics of the device are shown in Figure 6. Source current
is displayed as negative current in the figure; sink current is
positive. Note that the short-circuit current (that is, 0 V output)
is about 28 mA; when shorted to +15 V, the sink current goes to
about 20 mA.
1000
NOISE SPECTRAL DENSITY (nV/ Hz)
100
10
1
TOTAL NOISE (µV rms) UP
TO SPECIFIED FREQUENCY
+V = 15V
S
14
12
10
8
T
= 25°C
A
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 8. Spectral Noise Density and Total rms Noise vs. Frequency
1000
900
6
4
2
1.5µA/°C
0
800
–20 –15 –10
SOURCE
–5
0
5
10
SINK
15
20
OUTPUT CURRENT (mA)
700
Figure 6. Output Voltage vs. Sink and Source Current
DYNAMIC PERFORMANCE
600
500
Many low power instrument manufacturers have been in-
creasingly concerned with the turn-on characteristics of the
components used in their systems. Fast turn-on components often
enable the end user to keep power off when not needed, and yet
respond quickly when the power is turned on for operation.
Figure 7 displays the turn-on characteristic of the AD581. This
characteristic is generated from a cold start operation and repre-
sents the true turn-on waveform after an extended period with
the supplies off. The figure shows both the coarse and fine transient
characteristics of the device; the total settling time to within
10 mV is about 180 μs, and there is no long thermal tail
appearing after the point.
–55 –50 –40 –30 –20 –10
0
10 20 30 40 50 60 70 80 90 100 110 120 125
TEMPERATURE (°C)
Figure 9. Quiescent Current vs. Temperature
Rev. C | Page 7 of 12
AD581
PRECISION HIGH CURRENT SUPPLY
CONNECTION FOR REDUCED PRIMARY SUPPLY
The AD581 can be easily connected with power pnp or power
Darlington pnp devices to provide much greater output current
capability. The circuit shown in Figure 10 delivers a precision
10 V output with up to 4 A supplied to the load. The 0.1 μF
capacitor is required only if the load has a significant capacitive
component. If the load is purely resistive, improved high frequency
supply rejection results from removing the capacitor.
Whereas line regulation is specified down to 13 V, the typical
AD581 works as specified ≤12 V. The current sink capability
allows even lower supply voltage capability such as operation
from 12 V 5% as shown in Figure 11. The 560 Ω resistor reduces
the current supplied by the AD581 to a manageable level at a
full 5 mA load. Note that the other band gap references, without
current sink capability, may be damaged by use in this circuit
configuration.
V
≥ 15V
IN
12V ±5%
470Ω
+V
S
560Ω 5%
10V @ 0mA TO 5mA
AD581
V
OUT
GND
2N6040
Figure 11. 12 V Supply Connection
0.1µF
OUT
+V
S
V
V
OUT
10V @ 4A
AD581
GND
Figure 10. High Current Precision Supply
Rev. C | Page 8 of 12
AD581
THE AD581 AS A CURRENT LIMITER
The AD581 represents an alternative to current limiter diodes
that require factory selection to achieve a desired current. This
approach often results in temperature coefficients of 1%/°C.
The AD581 approach is not limited to a defined set current
limit; it can be programmed from 0.75 mA to 5 mA with the
insertion of a single external resistor. Of course, the minimum
voltage required to drive the connection is 13 V. The AD580,
which is a 2.5 V reference, can be used in this type of circuit
with compliance voltage down to 4.5 V.
ANALOG
GND
+V
S
0.1µF
AD581
V
OUT
GND
V
REF
–10V
1.2kΩ 5%
–15V
Figure 13. 2-Pin −10 V Reference
10 V REFERENCE WITH MULTIPLYING CMOS DACs
OR ADCs
+V
S
10V
R
~
___ + 0.75mA
10V =
i =
AD581
The AD581 is ideal for application with the entire AD7533
series of 10- and 12-bit multiplying CMOS DACs, especially for
low power applications. It is equally suitable for the AD7574
8-bit ADC. In the standard hook-up, as shown in Figure 15, the
+10 V reference is inverted by the amplifier/DAC configuration
to produce a 0 V to −10 V range. If an OP1177 amplifier is used,
total quiescent supply current is typically 2 mA. If a 0 V to +10 V
full-scale range is desired, the AD581 can be connected to the
CMOS DAC in its −10 V Zener mode, as shown in Figure 13
(the −10 VREF output is connected directly to the VREF IN of the
CMOS DAC). The AD581 is normally used in the −10 V mode
with the AD7574 to give a 0 V to +10 V ADC range. This is
shown in Figure 15. Bipolar output applications and other
operating details can be found in the data sheets for the CMOS
products.
V
OUT
R
LOAD
GND
BOTTOM VIEW OF
10V PRECISION
REFERENCE CIRCUIT
IN TO-5 CASE
Figure 12. A Two-Component Precision Current Limiter
NEGATIVE 10 V REFERENCE
The AD581 can also be used in a 2-pin Zener mode to provide a
precision −10.00 V reference. As shown in Figure 13, the +VS and
V
OUT pins are connected together to the high supply (in this
case, ground). The ground pin is connected through a resistor
to the negative supply. Thus, the output is taken from the
ground pin instead of VOUT. With 1 mA flowing through the
AD581 in this mode, a typical unit shows a 2 mV increase in
output level over that produced in the 3-pin mode. Note also
that the effective output impedance in this connection increases
from 0.2 Ω typical to 2 Ω. It is essential to arrange the output
load and the supply resistor, RS, so that the net current through
the AD581 is always between 1 mA and 5 mA. For operation to
+125°C, the net current should be between 2 mA and 5 mA. The
temperature characteristics and long-term stability of the device
are essentially the same as that of a unit used in the standard
3-pin mode.
+15V
+10V
AD581
V
REF IN
BIT 1 (MSB)
R
I
15
14
FEEDBACK
4
5
16
1
+15V
–15V
DIGITAL
INPUT
OUT1
V
OUT
0V TO –10V
I
OUT2
13
2
BIT 10 (LSB)
3
GND
The AD581 can also be used in a 2-pin mode to develop a
positive reference. +VS and VOUT are tied together and to the
positive supply through an appropriate supply resistor. The
performance characteristics are similar to those of the negative
2-pin connection. The only advantage of this connection over
the standard 3-pin connection is that a lower primary supply
can be used, as low as 10.5 V. This type of operation requires con-
siderable attention to load and primary supply regulation to
maintain the AD581 within its regulating range of 1 mA to 5 mA
(2 mA to 5 mA for operation beyond +85°C).
Figure 14. Low Power 10-Bit CMOS DAC Application
PRECISION 12-BIT DAC REFERENCE
AD565A, like most DACs, is designed to operate with a +10 V
reference element. In the AD565A, this 10 V reference voltage is
converted into a reference current of approximately 0.5 mA via
the internal 19.95 kΩ resistor (in series with the external 100 Ω
trimmer). The gain temperature coefficient of the AD565A is
primarily governed by the temperature tracking of the 19.95 kΩ
resistor and the 5 kꢀ to10 kꢀ span resistors; gain TC is guaran-
teed to 3 ppm/°C. Thus, using the AD581L (at 5 ppm/°C) as the
Rev. C | Page 9 of 12
AD581
+5V
–15V
R3
10 V reference guarantees a maximum full-scale temperature
coefficient of 8 ppm/°C over the commercial range. The 10 V
reference also supplies the normal 1 mA bipolar offset current
through the 9.95 kꢀ bipolar offset resistor. Consequently, the
bipolar offset TC depends only on TC matching of the bipolar
offset resistor to the input reference resistor and is guaranteed
to 3 ppm/°C.
1
GAIN TRIM
AD581
1.2kΩ
1
2
3
4
5
18
AD7574
(TOP VIEW)
5%
R2 2kΩ
GND
+V
S
–10V REF
DIGITAL
SUPPLY
RETURN
V
OUT
1
R1 1kΩ 10%
SIGNAL
INPUT
0.1µF
0V TO +10V
GROUND
INTERTIE
ANALOG
SUPPLY
RETURN
ANALOG
GROUND
1
R1 AND R2 CAN BE OMITTED IF GAIN TRIM
IS NOT REQUIRED.
Figure 15. AD581 as −10 V Reference for CMOS ADC
–15V +5V/+15V
24 23 22 21 20 19 18 17 16 15 14 13
0.1µF
6
1
2
0.1µF
11
10
5kΩ
(8kΩ)
+15V
PNP LOGIC SWITCHES AND LEVEL SHIFTERS
5kΩ
(8kΩ)
2
3
CONTROL AMP
SUMMING
0.5mA
4
9
+V
JUNCTION
OP1177
+15V
S
12
OP AMP
OUTPUT
CONTROL
AMP
GAIN ADJ.
10V
19.95kΩ
5
AD581
V
OUT
100Ω, 15T
A
R2
AD565A
R3
3.0MΩ
GND
8
7
R4
20kΩ, 15T
9.950kΩ
(15.95k)
3
–15V
UNIPOLAR
OFFSET ADJ.
A
–15V
R1
100Ω, 15T
BIPOLAR OFFSET ADJ.
A = ANALOG GROUND
Figure 16. Precision 12-Bit DAC
Rev. C | Page 10 of 12
AD581
OUTLINE DIMENSIONS
0.185 (4.70)
0.165 (4.19)
0.500 (12.70)
MIN
0.100 (2.54) TYP
3
0.045 (1.14)
0.029 (0.74)
0.200
(5.08)
TYP
2
0.034 (0.86)
0.028 (0.71)
1
0.019 (0.48)
0.016 (0.41)
0.030 (0.76) MAX
45°
BASE & SEATING PLANE
CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 17. 3-Pin Metal Header Package [TO-5]
(H-03B)
Dimensions shown in inches and (millimeters)
ORDERING GUIDE
Model
Temperature Range
0°C to +70°C
0°C to +70°C
Package Description
Package Option
H-03B
H-03B
H-03B
H-03B
AD581JH1
AD581KH1
AD581LH1
AD581SH1
AD581TH1
AD581UH1
3-Pin Metal Header Package (TO-5)
3-Pin Metal Header Package (TO-5)
3-Pin Metal Header Package (TO-5)
3-Pin Metal Header Package (TO-5)
3-Pin Metal Header Package (TO-5)
3-Pin Metal Header Package (TO-5)
0°C to +70°C
−55°C to +125°C
−55°C to +125°C
−55°C to +125°C
H-03B
H-03B
1 RoHS compliant model as of Date Code 0713.
Rev. C | Page 11 of 12
AD581
NOTES
©2009 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D08014-0-4/09(C)
Rev. C | Page 12 of 12
相关型号：
AD581U/883B
IC 1-OUTPUT THREE TERM VOLTAGE REFERENCE, 10 V, MBCY3, HERMETIC, TO-5, METAL, CAN-3, Voltage Reference
ADI
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