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. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
a
AD1582/AD1583/AD1584/AD1585
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700 www.analog.com
Fax: 781/326-8703 © Analog Devices, Inc., 2003
2.5 V to 5.0 V Micropower, Precision
Series Mode Voltage References
FUNCTIONAL BLOCK DIAGRAM
3-Lead SOT-23
(RT Suffix)
1
2
V
OUT
V
IN
GND
3
AD1582/
AD1583/
AD1584/
AD1585
TOP VIEW
FEATURES
Series Reference (2.5 V, 3 V, 4.096 V, 5 V)
Low Quiescent Current: 70 A max
Current Output Capability: 5 mA
Wide Supply Range: VIN = VOUT + 200 mV to 12 V
Wideband Noise (10 Hz–10 kHz): 50 V rms
Specified Temperature Range: –40C to +125C
Compact, Surface-Mount, SOT-23 Package
TARGET APPLICATIONS
1. Portable, battery-powered equipment. Notebook computers,
cellular phones, pagers, PDAs, GPSs, and DMMs.
2. Computer workstations. Suitable for use with a wide range of
video RAMDACs.
3. Smart industrial transmitters
4. PCMCIA cards
5. Automotive
6. Hard disk drives
7. 3 V/5 V 8-bit/12-bit data converters
I
SUPPLY
– A
V
SUPPLY
– V
800
700
0
2.7 5
400
300
200
100
600
500
*
3.076k SOURCE RESISTOR
SHUNT REFERENCE
*
AD1582 SERIES REFERENCE
900
Figure 1. Supply Current (
µ
A) vs. Supply Voltage (V)
AD158x Products, Three Electrical Grades
Electrical Tempco
Grade Initial Accuracy (ppmC)
AD1582 AD1583/AD1585 AD1584
B0.08% 0.10% 0.10% 50
C0.16% 0.20% 0.20% 50
A0.80% 1.00% 0.98% 100
GENERAL DESCRIPTION
The AD1582, AD1583, AD1584, and AD1585 are a family of low
cost, low power, low dropout, precision band gap references.
These designs are available as three-terminal (series) devices
and are packaged in the compact SOT-23, 3-lead, surface-mount
package. The versatility of these references makes them ideal for
use in battery-powered 3 V or 5 V systems where there may be
wide variations in supply voltage and a need to minimize power
dissipation.
The superior accuracy and temperature stability of the AD1582/
AD1583/AD1584/AD1585 is made possible by the precise
matching and thermal tracking of on-chip components. Patented
temperature drift curvature correction design techniques minimize
the nonlinearities in the voltage output temperature characteristic.
These series mode devices (AD1582/AD1583/AD1584/AD1585)
source or sink up to 5 mA of load current and operate efficiently
with only 200 mV of required headroom supply. This family
draws a maximum 70 µA of quiescent current with only a 1.0 µA/V
variation with supply voltage. The advantage of these designs
over conventional shunt devices is extraordinary. Valuable supply
current is no longer wasted through an input series resistor and
maximum power efficiency is achieved at all input voltage levels.
The AD1582, AD1583, AD1584, and AD1585 are available in
three grades, A, B, and C, which are provided in a tiny foot-
print, the SOT-23. All grades are specified over the industrial
temperature range of –40°C to +125°C.
AD1582/AD1583/AD1584/AD1585
–2– REV. C
AD1582–SPECIFICATIONS
AD1582A AD1582B AD1582C
Parameter Min Typ Max Min Typ Max Min Typ Max Unit
OUTPUT VOLTAGE (@ 25°C)
V
O
2.480 2.500 2.520 2.498 2.500 2.502 2.496 2.500 2.504 V
INITIAL ACCURACY ERROR (@ 25°C)
V
OERR
–20 +20 –2 +2 –4 +4 mV
–0.80 +0.80 –0.08 +0.08 –0.16 +0.16 %
OUTPUT VOLTAGE TEMPERATURE DRIFT 100 50 50 ppm/°C
TEMPERATURE COEFFICIENT (TCV
O
)
–40°C < T
A
< +125°C40100 18 50 18 50 ppm/°C
0°C < T
A
< 70°C351515ppm/°C
MINIMUM SUPPLY HEADROOM (V
IN
–V
OUT
)200 200 200 mV
LOAD REGULATION
0 mA < I
OUT
< 5 mA (–40°C to +85°C) 0.2 0.2 0.2 mV/mA
0 mA < I
OUT
< 5 mA (–40°C to +125°C) 0.4 0.4 0.4 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +85°C) 0.25 0.25 0.25 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +125°C) 0.45 0.45 0.45 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +85°C) 2.7 2.7 2.7 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +125°C) 3.5 3.5 3.5 mV/mA
LINE REGULATION
V
OUT
200 mV < V
IN
< 12 V
I
OUT
= 0 mA 25 25 25 µV/V
RIPPLE REJECTION (∆V
OUT
/∆V
IN
)
V
IN
= 5 V ± 100 mV (f = 120 Hz) 80 80 80 dB
QUIESCENT CURRENT 70 70 70 µA
SHORT CIRCUIT CURRENT TO GROUND 15 15 15 mA
NOISE VOLTAGE (@ 25°C)
0.1 Hz to 10 Hz 70 70 70 µV p-p
10 Hz to 10 kHz 50 50 50 µV rms
TURN-ON SETTLING TIME TO 0.1%,
C
L
= 0.2 µF100 100 100 µs
LONG-TERM STABILITY
1000 Hours @ 25°C100 100 100 ppm/1000 hrs.
OUTPUT VOLTAGE HYSTERESIS 115 115 115 ppm
TEMPERATURE RANGE
Specified Performance (A, B, C) –40 +125 –40 +125 –40 +125 °C
Operating Performance (A, B, C) –55 +125 –55 +125 –55 +125 °C
Specifications subject to change without notice.
(@ TA = TMIN to TMAX, VIN = 5 V, unless otherwise noted.)
–3–
REV. C
AD1582/AD1583/AD1584/AD1585
AD1583–SPECIFICATIONS
AD1583A AD1583B AD1583C
Parameter Min Typ Max Min Typ Max Min Typ Max Unit
OUTPUT VOLTAGE (@ 25°C)
V
O
2.970 3.000 3.030 2.997 3.000 3.003 2.994 3.000 3.006 V
INITIAL ACCURACY ERROR (@ 25°C)
V
OERR
–30 +30 –3 +3 –6 +6 mV
–1.0 +1.0 –0.1 +0.1 –0.20 +0.20 %
OUTPUT VOLTAGE TEMPERATURE DRIFT 100 50 50 ppm/°C
TEMPERATURE COEFFICIENT (TCV
O
)
–40°C < T
A
< +125°C40100 18 50 18 50 ppm/°C
0°C < T
A
< 70°C351515ppm/°C
MINIMUM SUPPLY HEADROOM (V
IN
–V
OUT
)200 200 200 mV
LOAD REGULATION
0 mA < I
OUT
< 5 mA (–40°C to +85°C) 0.25 0.25 0.25 mV/mA
0 mA < I
OUT
< 5 mA (–40°C to +125°C) 0.45 0.45 0.45 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +85°C) 0.40 0.40 0.40 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +125°C) 0.6 0.6 0.6 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +85°C) 2.9 2.9 2.9 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +125°C) 3.7 3.7 3.7 mV/mA
LINE REGULATION
V
OUT
200 mV < V
IN
< 12 V
I
OUT
= 0 mA 25 25 25 µV/V
RIPPLE REJECTION (∆V
OUT
/∆V
IN
)
V
IN
= 5 V ± 100 mV (f = 120 Hz) 80 80 80 dB
QUIESCENT CURRENT 70 70 70 µA
SHORT CIRCUIT CURRENT TO GROUND 15 15 15 mA
NOISE VOLTAGE (@ 25°C)
0.1 Hz to 10 Hz 85 85 85 µV p-p
10 Hz to 10 kHz 60 60 60 µV rms
TURN-ON SETTLING TIME TO 0.1%
C
L
= 0.2 µF120 120 120 µs
LONG-TERM STABILITY
1000 Hours @ 25°C100 100 100 ppm/1000 hrs.
OUTPUT VOLTAGE HYSTERESIS 115 115 115 ppm
TEMPERATURE RANGE
Specified Performance (A, B, C) –40 +125 –40 +125 –40 +125 °C
Operating Performance (A, B, C) –55 +125 –55 +125 –55 +125 °C
Specifications subject to change without notice.
(@ TA = TMIN to TMAX, VIN = 5 V, unless otherwise noted.)
AD1582/AD1583/AD1584/AD1585
–4– REV. C
AD1584–SPECIFICATIONS
AD1584A AD1584B AD1584C
Parameter Min Typ Max Min Typ Max Min Typ Max Unit
OUTPUT VOLTAGE (@ 25°C)
V
O
4.056 4.096 4.136 4.092 4.096 4.100 4.088 4.096 4.104 V
INITIAL ACCURACY ERROR (@ 25°C)
V
OERR
–40 +40 –4 +4 –8 +8 mV
–0.98 +0.98 –0.1 +0.1 –0.2 +0.2 %
OUTPUT VOLTAGE TEMPERATURE DRIFT 100 50 50 ppm/°C
TEMPERATURE COEFFICIENT (TCV
O
)
–40°C < T
A
< +125°C40100 18 50 18 50 ppm/°C
0°C < T
A
< 70°C351515ppm/°C
MINIMUM SUPPLY HEADROOM (V
IN
–V
OUT
)200 200 200 mV
LOAD REGULATION
0 mA < I
OUT
< 5 mA (–40°C to +85°C) 0.32 0.32 0.32 mV/mA
0 mA < I
OUT
< 5 mA (–40°C to +125°C) 0.52 0.52 0.52 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +85°C) 0.40 0.40 0.40 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +125°C) 0.6 0.6 0.6 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +85°C) 3.2 3.2 3.2 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +125°C) 4.1 4.1 4.1 mV/mA
LINE REGULATION
V
OUT
200 mV < V
IN
< 12 V
I
OUT
= 0 mA 25 25 25 µV/V
RIPPLE REJECTION (∆V
OUT
/∆V
IN
)
V
IN
= 5 V ± 100 mV (f = 120 Hz)
2
80 80 80 dB
QUIESCENT CURRENT 70 70 70 µA
SHORT CIRCUIT CURRENT TO GROUND 15 15 15 mA
NOISE VOLTAGE (@ 25°C)
0.1 Hz to 10 Hz 110 110 110 µV p-p
10 Hz to 10 kHz 90 90 90 µV rms
TURN-ON SETTLING TIME TO 0.1%
C
L
= 0.2 µF140 140 140 µs
LONG-TERM STABILITY
1000 Hours @ 25°C100 100 100 ppm/1000 hrs.
OUTPUT VOLTAGE HYSTERESIS 115 115 115 ppm
TEMPERATURE RANGE
Specified Performance (A, B, C) –40 +125 –40 +125 –40 +125 °C
Operating Performance (A, B, C) –55 +125 –55 +125 –55 +125 °C
Specifications subject to change without notice.
(@ TA = TMIN to TMAX, VIN = 5 V, unless otherwise noted.)
–5–
REV. C
AD1582/AD1583/AD1584/AD1585
AD1585–SPECIFICATIONS
AD1585A AD1585B AD1585C
Parameter Min Typ Max Min Typ Max Min Typ Max Unit
OUTPUT VOLTAGE (@ 25°C)
V
O
4.950 5.000 5.050 4.995 5.000 5.005 4.990 5.000 5.010 V
INITIAL ACCURACY ERROR (@ 25°C)
V
OERR
–50 +50 –5 +5 –10 +10 mV
–1.0 +1.0 –0.10 +0.10 –0.20 +0.20 %
OUTPUT VOLTAGE TEMPERATURE DRIFT 100 50 50 ppm/°C
TEMPERATURE COEFFICIENT (TCV
O
)
–40°C < T
A
< +125°C40100 18 50 18 50 ppm/°C
0°C < T
A
< 70°C351515ppm/°C
MINIMUM SUPPLY HEADROOM (V
IN
–V
OUT
)200 200 200 mV
LOAD REGULATION
0 mA < I
OUT
< 5 mA (–40°C to +85°C) 0.40 0.40 0.40 mV/mA
0 mA < I
OUT
< 5 mA (–40°C to +125°C) 0.6 0.6 0.6 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +85°C) 0.40 0.40 0.40 mV/mA
–5 mA < I
OUT
< 0 mA (–40°C to +125°C) 0.6 0.6 0.6 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +85°C) 4 4 4 mV/mA
–0.1 mA < I
OUT
< +0.1 mA (–40°C to +125°C) 4.8 4.8 4.8 mV/mA
LINE REGULATION
V
OUT
200 mV < V
IN
< 12 V
I
OUT
= 0 mA 25 25 25 µV/V
RIPPLE REJECTION (∆V
OUT
/∆V
IN
)
V
IN
= 6 V ± 100 mV (f = 120 Hz) 80 80 80 dB
QUIESCENT CURRENT 70 70 70 µA
SHORT CIRCUIT CURRENT TO GROUND 15 15 15 mA
NOISE VOLTAGE (@ 25°C)
0.1 Hz to 10 Hz 140 140 140 µV p-p
10 Hz to 10 kHz 100 100 100 µV rms
TURN-ON SETTLING TIME TO 0.1%
C
L
= 0.2 µF175 175 175 µs
LONG-TERM STABILITY
1000 Hours @ 25°C100 100 100 ppm/1000 hrs.
OUTPUT VOLTAGE HYSTERESIS 115 115 115 ppm
TEMPERATURE RANGE
Specified Performance (A, B, C) –40 +125 –40 +125 –40 +125 °C
Operating Performance (A, B, C) –55 +125 –55 +125 –55 +125 °C
Specifications subject to change without notice.
(@ TA = TMIN to TMAX, VIN = 6 V, unless otherwise noted.)
AD1582/AD1583/AD1584/AD1585
–6– REV. C
ABSOLUTE MAXIMUM RATINGS
1
V
IN
to Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 V
Internal Power Dissipation
2
SOT-23 (RT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 mW
Storage Temperature Range . . . . . . . . . . . . –65°C to +125°C
Specified Temperature Range
AD1582RT/AD1583RT/,
AD1584RT/AD1585RT . . . . . . . . . . . . . –40°C to +125°C
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
NOTES
1
Stresses above those listed under Absolute Maximum Ratings may cause perma-
nent 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.
2
Specification is for device in free air at 25°C: SOT-23 package: θ
JA
= 300°C/W.
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 AD1582/AD1583/AD1584/AD1585 feature 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.
PACKAGE BRANDING INFORMATION
Four fields identify the device:
•First field, product identifier, for example, a “2/3/4/5” identifies
the generic as AD1582/AD1583/AD1584/AD1585
•Second field, device grade, which can be “A,” “B,” or “C”
•Third field, calendar year of processing, “7” for 1997...,
“A” for 2001...
•Fourth field, two week window within the calendar year, for
example, letters A–Z to represent a two-week window starting
with “A” for the first two weeks of January.
ORDERING GUIDE
Initial Initial
Output Accuracy Accuracy Temperature Package Package Top Number of
Model Voltage (mV) % Coefficient Description Option Mark Parts per Reel
AD1582ART-Reel 2.50 20 0.80% 100 SOT-23 RT-3 2A0A 10,000
AD1582ART-Reel7 2.50 20 0.80% 100 SOT-23 RT-3 2A0A 3,000
AD1582BRT-Reel 2.50 2 0.08% 50 SOT-23 RT-3 2B0A 10,000
AD1582BRT-Reel7 2.50 2 0.08% 50 SOT-23 RT-3 2B0A 3,000
AD1582CRT-Reel 2.50 4 0.16% 50 SOT-23 RT-3 2C0A 10,000
AD1582CRT-Reel7 2.50 4 0.16% 50 SOT-23 RT-3 2C0A 3,000
AD1583ART-Reel 3.00 30 1.00% 100 SOT-23 RT-3 3A0A 10,000
AD1583ART-Reel7 3.00 30 1.00% 100 SOT-23 RT-3 3A0A 3,000
AD1583BRT-Reel 3.00 3 0.10% 50 SOT-23 RT-3 3B0A 10,000
AD1583BRT-Reel7 3.00 3 0.10% 50 SOT-23 RT-3 3B0A 3,000
AD1583CRT-Reel 3.00 6 0.20% 50 SOT-23 RT-3 3C0A 10,000
AD1583CRT-Reel7 3.00 6 0.20% 50 SOT-23 RT-3 3C0A 3,000
AD1584ART-Reel 4.096 40 0.98% 100 SOT-23 RT-3 4A0A 10,000
AD1584ART-Reel7 4.096 40 0.98% 100 SOT-23 RT-3 4A0A 3,000
AD1584BRT-Reel 4.096 4 0.10% 50 SOT-23 RT-3 4B0A 10,000
AD1584BRT-Reel7 4.096 4 0.10% 50 SOT-23 RT-3 4B0A 3,000
AD1584CRT-Reel 4.096 8 0.20% 50 SOT-23 RT-3 4C0A 10,000
AD1584CRT-Reel7 4.096 8 0.20% 50 SOT-23 RT-3 4C0A 3,000
AD1585ART-Reel 5.00 50 1.00% 100 SOT-23 RT-3 5A0A 10,000
AD1585ART-Reel7 5.00 50 1.00% 100 SOT-23 RT-3 5A0A 3,000
AD1585BRT-Reel 5.00 5 0.10% 50 SOT-23 RT-3 5B0A 10,000
AD1585BRT-Reel7 5.00 5 0.10% 50 SOT-23 RT-3 5B0A 3,000
AD1585CRT-Reel 5.00 10 0.20% 50 SOT-23 RT-3 5C0A 10,000
AD1585CRT-Reel7 5.00 10 0.20% 50 SOT-23 RT-3 5C0A 3,000
WARNING!
ESD SENSITIVE DEVICE
AD1582/AD1583/AD1584/AD1585
–7–
REV. C
PARAMETER DEFINITION
Temperature Coefficient (TCV
O
)
The change of output voltage over the operating temperature
change and normalized by the output voltage at 25⬚C, expressed
in ppm/⬚C. The equation follows:
TCV ppm C VT VT
VCTT
O
OO
O
/]°
[
=
()
−
()
°
()
×−
()
×
21
21
6
25 10
Where:
V
O
(25⬚C) = V
O
at 25⬚C
V
O
(T
1
) = V
O
at temperature1
V
O
(T
2
) = V
O
at temperature2
Line Regulation (∆V
O
/∆V
IN
)
The change in output voltage due to a specified change in input
voltage. It includes the effects of self-heating. Line regulation is
expressed in either percent per volt, parts-per-million per volt,
or microvolts per volt change in input voltage.
Load Regulation (∆V
O
/∆I
LOAD
)
The change in output voltage due to a specified change in load
current. It includes the effects of self-heating. Load Regulation
is expressed in either microvolts per milliampere, parts-per-million
per milliampere, or Ω of dc output resistance.
Long-Term Stability (∆V
O
)
Typical shift of output voltage at 25⬚C on a sample of parts
subjected to an operation life test of 1000 hours at 125⬚C:
∆
∆
VVtVt
V ppm Vt Vt
Vt
OO O
O
OO
O
=
()
−
()
[]
=
()
−
()
()
×
01
01
0
6
10
Where:
V
O
(t
0
) = V
O
at 25⬚C at time 0
V
O
(t
1
) = V
O
at 25⬚C after 1000 hours operation at 125⬚C
Thermal Hysteresis (V
O_HYS
)
The change of output voltage after the device is cycled through
temperatures from +25⬚C to –40⬚C to +85°C and back to +25⬚C.
This is a typical value from a sample of parts put through such
a cycle:
VVCV
V ppm VCV
VC
OHYS OOTC
OHYS
OOTC
O
__
_
_
=°
()
−
[]
=°
()
−
°
()
×
25
25
25 10
6
Where:
V
O
(25⬚C) = V
O
at 25⬚C
V
O_TC
= V
O
at 25⬚C after temperature cycle at +25⬚C to
–40⬚C to +85⬚C and back to +25⬚C
Operating Temperature
The temperature extremes at which the device can still function.
Parts may deviate from their specified performance outside the
specified temperature range.
AD1582/AD1583/AD1584/AD1585
–8– REV. C
–Typical Performance Characteristics
ppm/C
6
0
–60 50–50 –10 10
14
8
4
2
12
10
30
# OF PARTS
22
16
20
18
–40 –30 –20 0 20 40
TPC 1. Typical Output Voltage Temperature Drift
Distribution
VOUT – ERROR
50
15
0
–100% 1.00%–0.60% –0.20% 0.20% 0.60%
45
20
10
5
35
25
40
30
# OF PARTS
TPC 2. Typical Output Voltage Error Distribution
TEMPERATURE – C
–40 –20 0 20 40 60 80 100 120
VOUT
2.504
2.502
2.494
2.492
2.49
2.488
2.5
2.496
2.498
TPC 3. Typical Temperature Drift Characteristic Curves
VIN – V
024681012
0
0.25
0.20
0.15
0.10
0.35
0.30
0.40
0.05
AD1585
AD1582
mV/mA
TPC 4. Load Regulation vs. V
IN
–20
–40
–60
–80
–70
–30
–50
IOUT – mA
V/V
0
–90
–5 1–4 –3 –2 –1 0 2 3 4 5
–10
AD1585
AD1582
TPC 5. Line Regulation vs. I
LOAD
1E+04
1E+031E+021E+01
1E+02
1E+03
1E+04 1E+05
IOUT = 0
IOUT = 1mA
FREQUENCY – Hz
nV/ Hz
TPC 6. Noise Spectral Density
AD1582/AD1583/AD1584/AD1585
–9–
REV. C
THEORY OF OPERATION
The AD1582/AD1583/AD1584/AD1585 family uses the band gap
concept to produce stable, low temperature coefficient voltage
references suitable for high accuracy data acquisition components
and systems. This family of precision references uses the underlying
temperature characteristics of a silicon transistor’s base-emitter
voltage in the forward-biased operating region. Under this
condition, all such transistors have a –2 mV/°C temperature
coefficient (TC) and a V
BE
that, when extrapolated to absolute
zero, 0°K, (with collector current proportional to absolute
temperature) approximates the silicon band gap voltage. By
summing a voltage that has an equal and opposite temperature
coefficient of 2 mV/°C with the V
BE
of a forward-biased transistor,
an almost zero TC reference can be developed. In the AD1582/
AD1583/AD1584/AD1585 simplified circuit diagram shown in
Figure 2, such a compensating voltage, V1, is derived by
driving two transistors at different current densities and
amplifying the resultant V
BE
difference (∆V
BE
—which has a positive
TC). The sum of V
BE
and V1(V
BG
) is then buffered and ampli-
fied to produce stable reference voltage outputs of 2.5 V, 3 V,
4.096 V, and 5 V.
R3 R4
VBE R2 R6
R5
VOUT
VIN
VBG
GND
V1
+
–
R1
+
–
Figure 2. Simplified Schematic
APPLYING THE AD1582/AD1583/AD1584/AD1585
The AD1582/AD1583/AD1584/AD1585 is a family of series
references that can be used for many applications. To achieve
optimum performance with these references, only two external
components are required. Figure 3 shows the AD1582 configured
for operation under all loading conditions. With a simple 4.7 µF
capacitor attached to the input and a 1 µF capacitor applied
to the output, the devices can achieve specified performance for
all input voltage and output current requirements. For best
transient response, add a 0.1 µF capacitor in parallel with the 4.7 µF
capacitor. While a 1 µF output capacitor can provide stable
performance for all loading conditions, the AD1582 can operate
under low (–100 µA < I
OUT
< +100 µA) current conditions with
just a 0.2 µF output capacitor. The 4.7 µF capacitor on the input can
be reduced to 1 µF in this condition.
Unlike conventional shunt reference designs, the AD1582/
AD1583/AD1584/AD1585 family provides stable output voltages
at constant operating current levels. When properly decoupled,
as shown in Figure 3, these devices can be applied to any circuit
and provide superior low power solutions.
+
–
VOUT1F
1
2
VIN
4.7F
3
AD1582/
AD1583/
AD1584/
AD1585
Figure 3. Typical Connection Diagram
TEMPERATURE PERFORMANCE
The AD1582/AD1583/AD1584/AD1585 family of references is
designed for applications where temperature performance is
important. Extensive temperature testing and characterization
ensures that the device’s performance is maintained over the
specified temperature range.
The error band guaranteed with the AD1582/AD1583/AD1584/
AD1585 family is the maximum deviation from the initial value at
25°C. Thus, for a given grade of the AD1582/AD1583/AD1584/
AD1585, the designer can easily determine the maximum total
error by summing initial accuracy and temperature variation,
e.g., for the AD1582BRT, the initial tolerance is ±2mV, the
temperature error band is ±8 mV, thus the reference is guaranteed
to be 2.5 V ± 10 mV from –40°C to +125°C.
Figure 4 shows the typical output voltage drift for the AD1582
and illustrates the methodology. The box in Figure 4 is bounded on
the x-axis by operating temperature extremes. It is bounded
on the y-axis by the maximum and minimum output voltages
observed over the operating temperature range. The slope of the
diagonal drawn from the initial output value at 25°C to the output
values at +125°C and –40°C determines the performance grade of
the device.
Duplication of these results requires a test system that is highly
accurate with stable temperature control. Evaluation of the
AD1582 produces curves similar to those in TPC 3 and Figure 4,
but output readings may vary depending upon the test methods
and test equipment used.
TEMPERATURE – C
–40 –20 0 20 40 60 80 100 120
VOUT – V
2.504
2.502
2.496
2.494
2.492
2.5
2.498
Figure 4. Output Voltage vs. Temperature
AD1582/AD1583/AD1584/AD1585
–10– REV. C
VOLTAGE OUTPUT NONLINEARITY VERSUS
TEMPERATURE
When using a voltage reference with data converters, it is impor-
tant to understand the impact that temperature drift can have on
the converter’s performance. The nonlinearity of the reference
output drift represents additional error that cannot easily be
calibrated out of the overall system. To better understand the
impact such a drift can have on a data converter, refer to Figure 5
where the measured drift characteristic is normalized to the
endpoint average drift. The residual drift error of the AD1582
of approximately 200 ppm demonstrates that this family of
references is compatible with systems that require 12-bit accu-
rate temperature performance.
TEMPERATURE –
C
250
–50
–50 100–25 0 25 5075
200
150
100
50
0
V
OUT
– ppm
Figure 5. Residual Drift Error
OUTPUT VOLTAGE HYSTERESIS
High performance industrial equipment manufacturers may
require the AD1582/AD1583/AD1584/AD1585 family to maintain
a consistent output voltage error at 25°C after the references are
operated over the full temperature range. While all references
exhibit a characteristic known as output voltage hysteresis, the
AD1582/AD1583/AD1584/AD1585 family is designed to minimize
this characteristic. This phenomenon can be quantified by
measuring the change in the +25°C output voltage after
temperature excursions from +125°C to +25°C, and from –40°C
to +25°C. Figure 6 displays the distribution of the AD1582
output voltage hysteresis.
pp
m
–700 –450 –200 50 300 550
0
10
20
30
40
50
60
70
80
# OF PARTS
Figure 6. Output Voltage Hysteresis Distribution
SUPPLY CURRENT VERSUS TEMPERATURE
The quiescent current for the AD1582/AD1583/AD1584/AD1585
family of references varies slightly over temperature and input
supply range. Figure 7 demonstrates the typical performance
for the AD1582 reference when varying both temperature and
supply voltage. As is evident from the graph, the AD1582 supply
current increases only 1.0 µA/V, making this device extremely
attractive for use in applications where there may be wide varia-
tions in supply voltage and a need to minimize power dissipation.
VIN – V
IQ – A
100
80
034567891011
60
40
20
TA = +85C TA = +25C
TA = –40C
Figure 7. Typical Supply Current over Temperature
SUPPLY VOLTAGE
One of the ideal features of AD1582/AD1583/AD1584/AD1585 is
its low supply voltage headroom. The part can operate at
supply voltage as low as 200 mV above V
OUT
and up to 12 V.
However, if negative voltage is inadvertently applied to V
IN
with
respect to ground or any negative transient, >5 V is coupled to
V
IN
and the device may be damaged.
AD1582/AD1583/AD1584/AD1585
–11–
REV. C
AC PERFORMANCE
To apply the AD1582/AD1583/AD1584/AD1585 family of
references, it is important to understand the effects of dynamic
output impedance and power supply rejection. In Figure 8a, a
voltage divider is formed by the AD1582’s output impedance and
by the external source impedance. Figure 8b shows the effect of
varying the load capacitor on the reference output. Power supply
rejection ratio (PSRR) should be determined when characterizing
the ac performance of a series voltage reference. Figure 9a shows a
test circuit used to measure PSRR, and Figure 9b demonstrates
the AD1582’s ability to attenuate line voltage ripple.
2 VOUT
10k
10k
2V
100A
10k
2k
VLOAD DC 5V
5F
1F
DUT
1
Figure 8a. Output Impedance Test Circuit
100
1
0.1
10
FREQUENCY – Hz
1E+01 1E+02 1E+03 1E+04 1E+05 1E+06
1F CAP
AD1585
AD1582
Figure 8b. Output Impedance vs. Frequency
5V 100mV
0.22
FDUT
0.22
F
V
OUT
10V
10k
10k
200mV
1
Figure 9a. Ripple Rejection Test Circuit
FREQUENCY – Hz
100
90
0
1.E+00 1.E+061.E+01 1.E+02 1.E+03 1.E+04 1.E+05
50
20
PSRR – dB
80
70
60
40
30
10
AD1582
AD1585
Figure 9b. Ripple Rejection vs. Frequency
NOISE PERFORMANCE AND REDUCTION
The noise generated by the AD1582 is typically less then
70 µV p-p over the 0.1 Hz to 10 Hz frequency band. Figure 10
shows the 0.1 Hz to 10 Hz noise of a typical AD1582. The noise
measurement is made with a high gain band-pass filter. Noise in
a 10 Hz to 10 kHz region is approximately 50 µV rms. Figure 11
shows the broadband noise of a typical AD1582. If further noise
reduction is desired, a 1-pole low-pass filter may be added
between the output pin and the ground. A time constant of 0.2 ms
has a –3 dB point at roughly 800 Hz, and reduces the high
frequency noise to about 16 µV rms. It should be noted,
however, that while additional filtering on the output may improve
the noise performance of the AD1582/AD1583/AD1584/AD1585
family, the added output impedance could degrade the ac
performance of the references.
100
90
10
0%
10
V 1s
Figure 10. 0.1 Hz to10 Hz Voltage Noise
10
0%
100
90
10ms
100
V
Figure 11. 10 Hz to 10 kHz Wideband Noise
AD1582/AD1583/AD1584/AD1585
–12– REV. C
TURN-ON TIME
Many low power instrument manufacturers are becoming increas-
ingly concerned with the turn-on characteristics of the components
being used in their systems. Fast turn-on components often enable
the end user to save power by keeping power off when it is not
needed. Turn-on settling time is defined as the time required, after
the application of power (cold start), for the output voltage to
reach its final value within a specified error. The two major factors
affecting this are the active circuit settling time and the time
required for the thermal gradients on the chip to stabilize.
Figure 12a shows the turn-on settling and transient response test
circuit. Figure 12b shows the turn-on characteristic of the
AD1582. This characteristic is generated from cold-start operation
and represents the true turn-on waveform after power-up.
Figure 12c shows the fine settling characteristics of the AD1582.
Typically, the reference settles to within 0.1% of its final value
in about 100 µs.
The device can momentarily draw excessive supply current
when V
SUPPLY
is slightly below the minimum specified level.
Power supply resistance must be low enough to ensure reliable
turn-on. Fast power supply edges minimize this effect.
0V OR 10V
0V TO 10V
5V OR 10V
0V OR 5V
0.22F
DUT
0.22F
V
OUT
10k
10k
1
Figure 12a. Turn-On/Transient Response Test Circuit
10
0%
100
90
20
s
5V
20
s
1V
Figure 12b. Turn-On Characteristics
10
0%
100
90
20
s
5V
20
s
1mV
Figure 12c. Turn-On Settling
DYNAMIC PERFORMANCE
Many A/D and D/A converters present transient current loads
to the reference, and poor reference response can degrade the
converter’s performance. The AD1582/AD1583/AD1584/AD1585
family of references provides superior static and dynamic line
and load regulation. Since these series references are capable of
both sourcing and sinking large current loads, they exhibit
excellent settling characteristics.
Figure 13 displays the line transient response for the AD1582.
The circuit used to perform such a measurement is shown in
Figure 12a, where the input supply voltage is toggled from 5 V
to 10 V and the input and output capacitors are each 0.22 µF.
Figures 14 and 15 show the load transient settling characteristics
for the AD1582 when load current steps of 0 mA to +5 mA
and 0 mA to –1 mA are applied. The input supply voltage
remains constant at 5 V, the input decoupling and output load
capacitors are 4.7 µF and 1 µF respectively, and the output current
is toggled. For both positive and negative current loads, the
reference responses settle very quickly and exhibit initial voltage
spikes less than 10 mV.
10
0%
100
90
50
s
5V
50
s
200mV
Figure 13. Line Transient Response
10
0%
100
90
20
s
5V
20
s
5mV
Figure 14. Load Transient Response (0 mA to 5 mA Load)
10
0%
100
90
20
s
5V
20
s
5mV
Figure 15. Load Transient Response (0 mA to –1 mA Load)
AD1582/AD1583/AD1584/AD1585
–13–
REV. C
3-Lead Plastic Surface-Mount Package [SOT-23]
(RT-3)
Dimensions shown in millimeters
3.04
2.90
2.80
PIN 1
1.40
1.30
1.20 2.64
2.10
1.90 BSC
1 2
3
SEATING
PLANE
1.12
0.89
0.10
0.01
0.50
0.30 0.54
REF
0.20
0.08
0.60
0.50
0.40
0.95 BSC
COMPLIANT TO JEDEC STANDARDS TO-236AB
SOT-23 Tape and Reel
Dimensions shown in millimeters
4.10
4.00
3.90
1.55
1.50
1.50
8.30
8.00
7.70
3.20
3.10
2.90
2.05
2.00
1.95
1.85
1.75
1.65
3.55
3.50
3.45
2.80
2.70
2.60
1.10
1.00
0.90
0.35
0.30
0.25
13.20
13.00
12.80
9.90
8.40
8.40
20.20
MIN
1.50 MIN
7" REEL 100.00
OR
13" REEL 330.00
7" REEL 50.00 MIN
OR
13" REEL 100.00 MIN
14.40 MAX
0.75 MIN
DIRECTION OF UNREELING
1.00 MIN
OUTLINE DIMENSIONS
Revision History
Location Page
12/02—Data Sheet changed from REV. B to REV. C.
Changes to FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Changes to GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Changes SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Changes to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
TPC 3 replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Changes to TEMPERATURE PERFORMANCE section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 4 replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Changes to OUTPUT VOLTAGE HYSTERESIS section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
SOT-23 package updated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
–14–
–15–
–16–
C00701–0–1/03(C)
PRINTED IN U.S.A.
