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High Precision
a
FEATURES
Laser Trimmed to High Accuracy:
5.000 V 62.0 mV (M Grade)
Trimmed Temperature Coefficient:
2 ppm/8C max, 08C to +708C (M Grade)
5 ppm/8C max, –408C to +858C (B & L Grades)
10 ppm/8C max, –558C to +1258C (T Grade)
Low Noise, 100 nV/√
Noise Reduction Capability
Output Trim Capability
MIL-STD-883 Compliant Versions Available
Industrial Temperature Range SOICs Available
Output Capable of Sourcing or Sinking 10 mA
PRODUCT DESCRIPTION
The AD586 represents a major advance in the state-of-the-art in
monolithic voltage references. Using a proprietary ion-implanted
buried Zener diode and laser wafer trimming of high stability
thin-film resistors, the AD586 provides outstanding performance at low cost.
The AD586 offers much higher performance than most other
5 V references. Because the AD586 uses an industry standard
pinout, many systems can be upgraded instantly with the
AD586. The buried Zener approach to reference design provides lower noise and drift than bandgap voltage references. The
AD586 offers a noise reduction pin which can be used to further
reduce the noise level generated by the buried Zener.
The AD586 is recommended for use as a reference for 8-, 10-,
12-, 14- or 16-bit D/A converters which require an external
precision reference. The device is also ideal for successive
approximation or integrating A/D converters with up to 14 bits
of accuracy and, in general, can offer better performance than
the standard on-chip references.
The AD586J, K, L and M are specified for operation from 0°C
to +70°C, the AD586A and B are specified for –40°C to +85°C
operation, and the AD586S and T are specified for –55°C to
+125°C operation. The AD586J, K, L and M are available in an
8-pin plastic DIP. The AD586J, K, L, A and B are available in
an 8-pin plastic surface mount small outline (SO) package. The
AD586J, K, L, S and T are available in an 8-pin cerdip package.
Hz
5 V Reference
AD586
FUNCTIONAL BLOCK DIAGRAM
PRODUCT HIGHLIGHTS
1. Laser trimming of both initial accuracy and temperature
coefficients results in very low errors over temperature without the use of external components. The AD586M has a
maximum deviation from 5.000 V of ± 2.45 mV between
0°C and +70°C, and the AD586T guarantees ± 7.5 mV
maximum total error between –55°C and +125°C.
2. For applications requiring higher precision, an optional finetrim connection is provided.
3. Any system using an industry standard pinout reference can
be upgraded instantly with the AD586.
4. Output noise of the AD586 is very low, typically 4 µV p-p. A
noise reduction pin is provided for additional noise filtering
using an external capacitor.
5. The AD586 is available in versions compliant with MILSTD-883. Refer to the Analog Devices Military Products
Databook or current AD586/883B data sheet for detailed
specifications.
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 Fax: 617/326-8703
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AD586–SPECIFICA TIONS
(@ TA = + 25°C, VIN = +15 V unless otherwise noted)
Model Min Typ Max Min Typ Max Min Typ Max Min Typ Max Min Typ Max Min Typ Max Units
Output Voltage 4.980 5.020 4.995 5.005 4.9975 5.0025 4.998 5.002 4.990 5.010 4.9975 5.0025 V
1
MAX
MAX
l
OUT
MAX
l
< 10 mA
< 0 mA
OUT
Output Voltage Drift
0°C to +70°C 25 15 5 2 ppm/°C
–55°C to +125°C 20 10
Gain Adjustment +6 +6 +6 +6 +6 +6 %
Line Regulation
10.8 V < +VIN < 36 V
T
to T
MIN
11.4 V < +VIN < 36 V
T
to T
MIN
Load Regulation
Sourcing 0 < I
25°C 100 100 100 100 150 150 µV/mA
T
to T
MIN
Sinking –10 < I
25°C 400 400 400 400 400 400
Quiescent Current 2 3 2 3 2 3 2 3 2 3 2 3 mA
Power Consumption 30 30 30 30 30 30 mW
Output Noise
0.1 Hz to 10 Hz 4 4 4 4 4 4 µV p-p
Spectral Density, 100 Hz 100 100 100 100 100 100 nV/√Hz
AD586J AD586K/A AD586L/B AD586M AD586S AD586T
–2 –2 –2 –2 –2 –2
100 100 100 100 ±µV/V
150 150
100 100 100 100 150 150
Long-Term Stability 15 15 15 15 15 15 ppm/1000 Hr
Short-Circuit Current-to-Ground 45 60 45 60 45 60 45 60 45 60 45 60 mA
Temperature Range
Specified Performance
Operating Performance
NOTES
1
Maximum output voltage drift is guaranteed for all packages and grades. Cerdip packaged parts are also 100°C production tested.
2
Lower row shows specified performance for A and B grades.
3
The operating temperature range is defined as the temperatures extremes at which the device will still function. Parts may deviate from their specified performance outside their
specified temperature range.
Specifications subject to change without notice.
Specifications in boldface are rested on all production units at final electrical test. Results from those tests are used to calculate outgoing quality levels. All min and max specifications are guaranteed, although only those shown in boldface are tested on all production units unless otherwise specified.
ABSOLUTE MAXIMUM RATINGS
VIN to Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 V
Power Dissipation
2
3
(25°C) . . . . . . . . . . . . . . . . . . . . . 500 mW
0 +70 0 +70 0 +70 0 +70 –55 +125 –55 +125 °C
–40 +85 –40 +85
–40 +85 –40 +85 – 40 +85 –40 +85 –55 +125 –55 +125
*
CONNECTION DIAGRAM
(Top View)
Storage Temperature . . . . . . . . . . . . . . . . . . –65°C to +150°C
Lead Temp (Soldering, 10 sec) . . . . . . . . . . . . . . . . . . +300°C
Package Thermal Resistance
θ
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22°C/W
JC
θ
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110°C/W
JA
Output Protection: Output safe for indefinite short to ground or
V
.
IN
*Stresses above those listed under “Absolute Maximum Ratings” may cause
permanent damage to the device. This is a stress rating only and 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.
–2–
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The following specifications are tested at the die level for AD586JCHIPS. These die are probed at 258C
WARNING!
ESD SENSITIVE DEVICE
DlE SPECIFlCATIONS
only. (TA = +258C, VIN = +15 V unless otherwise noted)
AD586JCHIPS
Parameter Min Typ Max Units
Output Voltage 4.980 5.020 V
Gain Adjustment +6 %
–2 %
Line Regulation
10.8 V < + V
< 36 V 100 ±µ V/V
IN
Load Regulation
Sourcing 0 < I
Sinking –10 < I
< 10 mA 100 µV/mA
OUT
< 0 mA 400 µV/mA
OUT
Quiescent Current 3 mA
Short-Circuit Current-to-Ground 60 mA
NOTES
1
Both V
Die Thickness: The standard thickness of Analog Devices Bipolar dice is 24 mils ± 2 mils.
Die Dimensions: The dimensions given have a tolerance of ±2 mils.
Backing: The standard backside surface is silicon (not plated). Analog Devices does not
recommend gold-backed dice for most applications.
Edges: A diamond saw is used to separate wafers into dice thus providing perpendicular
edges half-way through the die.
In contrast to scribed dice, this technique provides a more uniform die shape and size. The
perpendicular edges facilitate handling (such as tweezer pick-up) while the uniform shape
and size simplifies substrate design and die attach.
Top Surface: The standard top surface of the die is covered by a layer of glassivation. All
areas are covered except bonding pads and scribe lines.
Surface Metalization: The metalization to Analog Devices bipolar dice is aluminum.
Minimum thickness is 10,000Å.
Bonding Pads: All bonding pads have a minimum size of 4 mils by 4 mils. The passivation
windows have 3.5 mils by 3.5 mils minimum.
pads should be connected to the output.
OUT
AD586
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 the AD586 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. C
ORDERING GUIDE
Initial Temperature Temperature Package
Error Coefficient Range Option
Model
1
AD586JN 20 mV 25 ppm/°C0°C to +70°C N-8
AD586JQ 20 mV 25 ppm/°C0°C to +70°C Q-8
AD586JR 20 mV 25 ppm/°C0°C to +70°C SO-8
AD586KN 5 mV 15 ppm/°C0°C to +70°C N-8
AD586KQ 5 mV 15 ppm/°C0°C to +70°C Q-8
AD586KR 5 mV 15 ppm/°C0°C to +70°C SO-8
AD586LN 2.5 mV 5 ppm/°C0°C to +70°C N-8
AD586LR 2.5 mV 5 ppm/°C0°C to +70°C SO-8
AD586MN 2 mV 2 ppm/°C0°C to +70°C N-8
AD586AR 5 mV 15 ppm/°C–40°C to +85°C SO-8
AD586BR 2.5 mV 5 ppm/°C–40°C to +85°C SO-8
AD586LQ 2.5 mV 5 ppm/°C0°C to +70°C Q-8
AD586SQ 10 mV 20 ppm/°C –55°C to +125°C Q-8
AD586TQ 2.5 mV 10 ppm/°C –55°C to +125°C Q-8
AD586JCHIPS 20 mV 25 ppm/°C0°C to +70°C
NOTES
1
For details on grade and package offerings screened in accordance with MIL-STD-883, refer to the Analog Devices Military
Products Databook or current AD586/883B data sheet.
2
N = Plastic DIP; Q = Cerdip; SO = Small Outline IC (SOIC).
–3–
2
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AD586
THEORY OF OPERATION
The AD586 consists of a proprietary buried Zener diode reference, an amplifier to buffer the output and several high stability
thin-film resistors as shown in the block diagram in Figure 1.
This design results in a high precision monolithic 5 V output
reference with initial offset of 2.0 mV or less. The temperature
compensation circuitry provides the device with a temperature
coefficient of under 2 ppm/°C.
Using the bias compensation resistor between the Zener output
and the noninverting input to the amplifier, a capacitor can be
added at the NOISE REDUCTION pin (Pin 8) to form a lowpass filter and reduce the noise contribution of the Zener to the
circuit.
NOISE PERFORMANCE AND REDUCTION
The noise generated by the AD586 is typically less than 4 µV
p-p over the 0.1 Hz to 10 Hz band. Noise in a 1 MHz bandwidth is approximately 200 µV p-p. The dominant source of this
noise is the buried Zener which contributes approximately
100 nV/√
gible. Figure 3 shows the 0.1 Hz to 10 Hz noise of a typical
AD586. The noise measurement is made with a bandpass filter
made of a 1-pole high-pass filter with a corner frequency at
0.1 Hz and a 2-pole low-pass filter with a corner frequency at
12.6 Hz to create a filter with a 9.922Hz bandwidth.
If further noise reduction is desired, an external capacitor may
be added between the NOISE REDUCTION pin and ground as
shown in Figure 2. This capacitor, combined with the 4kΩ R
and the Zener resistances form a low-pass filter on the output of
the Zener cell. A 1 µF capacitor will have a 3 dB point at 12 Hz,
and it will reduce the high frequency (to 1MHz) noise to about
160 µV p-p. Figure 4 shows the 1 MHz noise of a typical AD586
both with and without a 1 µF capacitor.
Hz. In comparison, the op amp’s contribution is negli-
S
Figure 1. AD586 Functional Block Diagram
APPLYING THE AD586
The AD586 is simple to use in virtually all precision reference
applications. When power is applied to Pin 2 and Pin 4 is
grounded, Pin 6 provides a 5 V output. No external components
are required; the degree of desired absolute accuracy is achieved
simply by selecting the required device grade. The AD586 requires less than 3 mA quiescent current from an operating supply of +12 V or +15 V.
An external fine trim may be desired to set the output level to
exactly 5.000 V (calibrated to a main system reference). System
calibration may also require a reference voltage that is slightly
different from 5.000 V, for example, 5.12 V for binary applications. In either case, the optional trim circuit shown in Figure 2
can offset the output by as much as 300mV, if desired, with
minimal effect on other device characteristics.
Figure 2. Optional Fine Trim Configuration
Figure 3. 0.1 Hz to 10 Hz Noise
Figure 4. Effect of 1µF Noise Reduction Capacitor on
Broadband Noise
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 5 shows the turn-on characteristics of the
AD586. It shows the settling to be about 60µsec to 0.01%.
Note the absence of any thermal tails when the horizontal scale
is expanded to l ms/cm in Figure 5b.
–4–
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AD586
Output turn-on time is modified when an external noise reduction capacitor is used. When present, this capacitor acts as an
additional load to the internal Zener diode’s current source, resulting in a somewhat longer turn-on time. In the case of a 1 µF
capacitor, the initial turn-on time is approximately 400 ms to
0.01% (see Figure 5c).
DYNAMIC PERFORMANCE
The output buffer amplifier is designed to provide the AD586
with static and dynamic load regulation superior to less complete references.
Many A/D and D/A converters present transient current loads
to the reference, and poor reference response can degrade the
converter’s performance.
Figure 6 displays the characteristics of the AD586 output amplifier driving a 0 mA to 10 mA load.
REV. C
Figure 5. Turn-On Characteristics
–5–
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AD586
In some applications, a varying load may be both resistive and
capacitive in nature, or the load may be connected to the
AD586 by a long capacitive cable.
Figure 7 displays the output amplifier characteristics driving a
1000 pF, 0 to 10 mA load.
Figure 7a. Capacitive Load Transient Response Test Circuit
Centigrade; i.e., ppm/°C. However, because of nonlinearities in
temperature characteristics which originated in standard Zener
references (such as “S” type characteristics), most manufacturers have begun to use a maximum limit error band approach to
specify devices. This technique involves the measurement of the
output at three or more different temperatures to specify an output voltage error band.
Figure 9 shows the typical output voltage drift for the AD586L
and illustrates the test methodology. The box in Figure 9 is
bounded on the sides by the operating temperature extremes,
and on the top and the bottom by the maximum and minimum
output voltages measured over the operating temperature range.
The slope of the diagonal drawn from the lower left to the upper
right corner of the box determines the performance grade of the
device.
Figure 7b. Output Response with Capacitive Load
LOAD REGULATION
The AD586 has excellent load regulation characteristics. Figure
8 shows that varying the load several mA changes the output by
a few µV. The AD586 has somewhat better load regulation per-
formance sourcing current than sinking current.
Figure 8. Typical Load Regulation Characteristics
TEMPERATURE PERFORMANCE
The AD586 is designed for precision reference applications
where temperature performance is critical. Extensive temperature testing ensures that the device’s high level of performance is
maintained over the operating temperature range.
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
–6–
Figure 9. Typical AD586L Temperature Drift
Each AD586J, K and L grade unit is tested at 0°C, +25°C and
+70°C. Each AD586SQ and TQ grade unit is tested at –55°C,
+25°C and +125°C. This approach ensures that the variations
of output voltage that occur as the temperature changes within
the specified range will be contained within a box whose diagonal has a slope equal to the maximum specified drift. The position of the box on the vertical scale will change from device to
device as initial error and the shape of the curve vary. The maximum height of the box for the appropriate temperature range
and device grade is shown in Figure 10. Duplication of these
results requires a combination of high accuracy and stable temperature control in a test system. Evaluation of the AD586 will
produce a curve similar to that in Figure 9, but output readings
may vary depending on the test methods and equipment utilized.
DEVICE MAXIMUM OUTPUT CHANGE
GRADE (mV)
08C TO +708C –408C TO +858C –558C TO +1258C
AD586J 8.75
AD586K 5.25
AD586L 1.75
AD586M 0.70
AD586A 3.12
AD586B 9.37
AD586S 18.00
AD586T 9.00
Figure 10. Maximum Output Change in mV
REV. C
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NEGATIVE REFERENCE VOLTAGE FROM AN AD586
The AD586 can be used to provide a precision –5.000V output
as shown in Figure 11. The V
pin is tied to at least a +6 V
IN
supply, the output pin is grounded, and the AD586 ground pin
is connected through a resistor, R
, to a –15 V supply. The –5 V
S
output is now taken from the ground pin (Pin 4) instead of
V
It is essential to arrange the output load and the supply
OUT.
resistor R
so that the net current through the AD586 is be-
S
tween 2.5 mA and 10.0 mA. The temperature characteristics
and long-term stability of the device will be essentially the same
as that of a unit used in the standard +5 V output configuration.
Figure 11. AD586 as a Negative 5 V Reference
USING THE AD586 WITH CONVERTERS
The AD586 is an ideal reference for a wide variety of 8-, 12-,
14- and 16-bit A/D and D/A converters. Several representative
examples follow.
AD586
Figure 13. AD586 as a 5 V Reference for a CMOS
Dual DAC
STACKED PRECISION REFERENCES FOR
MULTIPLE VOLTAGES
Often, a design requires several reference voltages. Three
AD586s can be stacked, as shown in Figure 14, to produce
+5.000 V, +10.000 V, and +15.000 V outputs. This scheme
can be extended to any number of AD586s as long as the
maximum load current is not exceeded. This design provides the additional advantage of improved line regulation
on the +5.0 V output. Changes in V
produces an output change that is below the noise level of
the references.
of +18 V to +50 V
IN
5 V REFERENCE WITH MULTIPLYING CMOS D/A OR
A/D CONVERTERS
The AD586 is ideal for applications with 10- and 12-bit multiplying CMOS D/A converters. In the standard hookup, as
shown in Figure 12, the AD586 is paired with the AD7545
12-bit multiplying DAC and the AD711 high-speed BiFET Op
Amp. The amplifier DAC configuration produces a unipolar
0 V to –5 V output range. Bipolar output applications and other
operating details can be found on the individual product data
sheets.
Figure 12. Low-Power 12-Bit CMOS DAC Application
The AD586 can also be used as a precision reference for multiple DACs. Figure 13 shows the AD586, the AD7628 dual
DAC and the AD712 dual op amp hooked up for single supply
operation to produce 0 V to –5 V outputs. Because both DACs
are on the same die and share a common reference and output
op amps, the DAC outputs will exhibit similar gain TCs.
Figure 14. Multiple AD586s Stacked for Precision 5 V,
10 V and 15 V Outputs
REV. C
–7–
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AD586
PRECISION CURRENT SOURCE
The design of the AD586 allows it to be easily configured as a
current source. By choosing the control resistor R
you can vary the load current from the quiescent current (2mA
typically) to approximately 10 mA. The compliance voltage of
this circuit varies from about +5 V to +21 V depending upon
the value of V
PRECISION HIGH CURRENT SUPPLY
.
IN
For higher currents, the AD586 can easily be connected to a
power PNP or power Darlington PNP device. The circuit in
Figure 16 can deliver up to 4 amps to the load. The 0.1µF
in Figure 15,
C
Figure 15. Precision Current Source
capacitor is required only if the load has a significant capacitive
component. If the load is purely resistive, improved highfrequency supply rejection results can be obtained by removing
the capacitor.
C1069b–2–10/93
Figure 16a. Precision High-Current Current Source
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm.)
Mini-DIP (N-8) Package Cerdip (Q-8) Package Small Outline (R-8) Package
Figure 16b. Precision High-Current Voltage Source
PRINTED IN U.S.A.
–8–
REV. C
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