AD ADR391AUJZ-REEL7 Precision low drift 2.048 v/2.5 v/4.096 v/ 5.0 v sot-23 reference with shutdown Datasheet

Micropower, Low Noise Precision Voltage
References with Shutdown
ADR390/ADR391/ADR392/ADR395
FEATURES
APPLICATIONS
Battery-powered instrumentation
Portable medical instrumentation
Data acquisition systems
Industrial process controls
Automotive
FUNCTIONAL BLOCK DIAGRAM
SHDN 1
VIN 2
ADR390/
ADR391/
ADR392/
ADR395
5
GND
VOUT (SENSE) 3 (Not to Scale) 4 V
OUT (FORCE)
00419-D-001
Compact TSOT-23-5 packages
Low temperature coefficient
B grade: 9 ppm/°C
A grade: 25 ppm/°C
Initial accuracy
B grade: ±4 mV maximum
A grade: ±6 mV maximum
Ultralow output noise: 5 µV p-p (0.1 Hz to 10 Hz)
Low dropout: 300 mV
Low supply current
3 µA maximum in shutdown
120 µA maximum in operation
No external capacitor required
Output current: 5 mA
Wide temperature range
−40°C to + 125°C
Figure 1. 5-Lead TSOT (UJ Suffix)
Table 1.
Model
ADR390B
ADR390A
ADR391B
ADR391A
ADR392B
ADR392A
ADR395B
ADR395A
VOUT (V)
2.048
2.048
2.5
2.5
4.096
4.096
5.0
5.0
Temperature
Coefficient (ppm/°C)
9
25
9
25
9
25
9
25
Accuracy (mV)
±4
±6
±4
±6
±5
±6
±5
±6
GENERAL DESCRIPTION
The ADR390, ADR391, ADR392, and ADR395 are precision
2.048 V, 2.5 V, 4.096 V, and 5 V band gap voltage references,
respectively, featuring low power and high precision in a tiny
footprint. Using ADI’s patented temperature drift curvature
correction techniques, the ADR39x references achieve a low
9 ppm/°C of temperature drift in the TSOT package.
The ADR39x family of micropower, low dropout voltage
references provides a stable output voltage from a minimum
supply of 300 mV above the output. Their advanced design
eliminates the need for external capacitors, which further
reduces board space and system cost. The combination of
low power operation, small size, and ease of use makes the
ADR39x precision voltage references ideally suited for batteryoperated applications.
Rev. F
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.
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Fax: 781.461.3113
© 2005 Analog Devices, Inc. All rights reserved.
ADR390/ADR391/ADR392/ADR395
TABLE OF CONTENTS
ADR390 Specifications .................................................................... 3
Terminology .......................................................................................8
ADR391 Specifications .................................................................... 4
Typical Performance Characteristics ..............................................9
ADR392 Specifications .................................................................... 5
Theory of Operation ...................................................................... 16
ADR395 Specifications .................................................................... 6
Applications..................................................................................... 17
Absolute Maximum Ratings............................................................ 7
Basic Voltage Reference Connection ....................................... 17
Thermal Resistance ...................................................................... 7
Outline Dimensions ....................................................................... 19
ESD Caution.................................................................................. 7
Ordering Guide .......................................................................... 19
REVISION HISTORY
5/05—Rev. E to Rev. F
Changes to Table 5........................................................................... 7
Changes to Figure 2......................................................................... 9
4/04—Rev. D to Rev. E
Changes to ADR390—Specifications............................................ 3
Changes to ADR391—Specifications............................................ 4
Changes to ADR392—Specifications............................................ 5
Changes to ADR395—Specifications............................................ 6
4/04—Rev. C to Rev. D
Updated Format................................................................ Universal
Changes to Title ............................................................................... 1
Changes to Features......................................................................... 1
Changes to Applications ................................................................. 1
Changes to General Description ................................................... 1
Changes to Table 1........................................................................... 1
Changes to ADR390—Specifications............................................ 3
Changes to ADR391—Specifications............................................ 4
Changes to ADR392—Specifications............................................ 5
Changes to ADR395—Specifications............................................ 6
Changes to Absolute Maximum Ratings ...................................... 7
Changes to Thermal Resistance..................................................... 7
Moved ESD Caution........................................................................ 7
Changes to Figure 3, Figure 4, Figure 7, and Figure 8 ................ 9
Changes to Figure 11, Figure 12, Figure 13, and Figure 14...... 10
Changes to Figure 15, Figure 16, Figure 19, and Figure 20...... 11
Changes to Figure 23 and Figure 24............................................ 12
Changes to Figure 27..................................................................... 13
Changes to Ordering Guide ......................................................... 19
Updated Outline Dimensions...................................................... 19
10/02—Rev. B to Rev. C
Add parts ADR392 and ADR395 ....................................Universal
Changes to Features ........................................................................ 1
Changes to General Description ................................................... 1
Additions to Table I......................................................................... 1
Changes to Specifications............................................................... 2
Changes to Ordering Guide ........................................................... 4
Changes to Absolute Maximum Ratings...................................... 4
New TPCs 3, 4, 7, 8, 11, 12, 15, 16, 19, and 20 ............................ 6
New Figures 4 and 5...................................................................... 13
Deleted A Negative Precision Reference
without Precision Resistors Section ............................................ 13
Edits to General-Purpose Current Source Section ................... 13
Updated Outline Dimensions...................................................... 15
5/02—Rev. A to Rev. B
Edits to Layout ...................................................................Universal
Changes to Figure 6....................................................................... 13
Revision 0: Initial Version
Rev. F | Page 2 of 20
ADR390/ADR391/ADR392/ADR395
ADR390 SPECIFICATIONS
Electrical characteristics, VIN = 2.5 V to 15 V, TA = 25°C, unless otherwise noted.
Table 2.
Parameter
OUTPUT VOLTAGE
TEMPERATURE COEFFICIENT
Symbol
VO
VO
VOERR
VOERR
VOERR
VOERR
TCVO
SUPPLY VOLTAGE HEADROOM
LINE REGULATION
LOAD REGULATION
VIN − VO
∆VO/∆VIN
∆VO/∆ILOAD
QUIESCENT CURRENT
IIN
VOLTAGE NOISE
TURN-ON SETTLING TIME
LONG-TERM STABILITY1
OUTPUT VOLTAGE HYSTERESIS
RIPPLE REJECTION RATIO
SHORT CIRCUIT TO GND
en p-p
tR
∆VO
∆VO_HYS
RRR
ISC
SHUTDOWN PIN
Shutdown Supply Current
Shutdown Logic Input Current
Shutdown Logic Low
Shutdown Logic High
ISHDN
ILOGIC
VINL
VINH
INITIAL ACCURACY
1
Conditions
A grade
B grade
A grade
A grade
B grade
B grade
A grade: −40°C < TA < +125°C
B grade: −40°C < TA < +125°C
Min
2.042
2.044
Typ
2.048
2.048
Max
2.054
2.052
6
0.29
4
0.19
25
9
10
25
60
140
120
140
300
VIN = 2.5 V to 15 V, −40°C < TA < +125°C
ILOAD = 0 mA to 5 mA, −40°C < TA < +85°C, VIN = 3 V
ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 3 V
No load
−40°C < TA < +125°C
0.1 Hz to 10 Hz
5
20
50
100
80
25
30
1000 hours
fIN = 60 kHz
VIN = 5 V
VIN = 15 V
3
500
0.8
2.4
The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period.
Rev. F | Page 3 of 20
Unit
V
V
mV
%
mV
%
ppm/°C
ppm/°C
mV
ppm/V
ppm/mA
ppm/mA
µA
µA
µV p-p
µs
ppm
ppm
dB
mA
mA
µA
nA
V
V
ADR390/ADR391/ADR392/ADR395
ADR391 SPECIFICATIONS
Electrical characteristics, VIN = 2.8 V to 15 V, TA = 25°C, unless otherwise noted.
Table 3.
Parameter
OUTPUT VOLTAGE
INITIAL ACCURACY
TEMPERATURE COEFFICIENT
Symbol
VO
VO
VOERR
VOERR
VOERR
VOERR
TCVO
Conditions
A grade
B grade
A grade
A grade
B grade
B grade
A grade, −40°C < TA < +125°C
Min
2.494
2.496
Typ
2.5
2.5
B grade, −40°C < TA < +125°C
SUPPLY VOLTAGE HEADROOM
LINE REGULATION
LOAD REGULATION
VIN − VO
∆VO/∆VIN
∆VO/∆ILOAD
QUIESCENT CURRENT
IIN
VOLTAGE NOISE
TURN-ON SETTLING TIME
LONG-TERM STABILITY1
OUTPUT VOLTAGE HYSTERESIS
RIPPLE REJECTION RATIO
SHORT CIRCUIT TO GND
enp-p
tR
∆VO
∆VO_HYS
RRR
ISC
SHUTDOWN PIN
Shutdown Supply Current
Shutdown Logic Input Current
Shutdown Logic Low
Shutdown Logic High
ISHDN
ILOGIC
VINL
VINH
1
Max
2.506
2.504
6
0.24
4
0.16
25
Unit
V
V
mV
%
mV
%
ppm/°C
9
ppm/°C
300
VIN = 2.8 V to 15 V, −40°C < TA < +125°C
ILOAD = 0 mA to 5 mA, −40°C < TA < +85°C, VIN = 3 V
ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 3 V
No load
−40°C < TA < +125°C
0.1 Hz to 10 Hz
10
25
60
140
120
140
5
20
50
100
80
25
30
1000 hours
fIN = 60 kHz
VIN = 5 V
VIN = 15 V
3
500
0.8
2.4
The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period.
Rev. F | Page 4 of 20
mV
ppm/V
ppm/mA
ppm/mA
µA
µA
µV p-p
µs
ppm
ppm
dB
mA
mA
µA
nA
V
V
ADR390/ADR391/ADR392/ADR395
ADR392 SPECIFICATIONS
Electrical characteristics, VIN = 4.3 V to 15 V, TA = 25°C, unless otherwise noted.
Table 4.
Parameter
OUTPUT VOLTAGE
TEMPERATURE COEFFICIENT
Symbol
VO
VO
VOERR
VOERR
VOERR
VOERR
TCVO
SUPPLY VOLTAGE HEADROOM
LINE REGULATION
LOAD REGULATION
QUIESCENT CURRENT
VIN − VO
∆VO/∆VIN
∆VO/∆ILOAD
IIN
VOLTAGE NOISE
TURN-ON SETTLING TIME
LONG-TERM STABILITY1
OUTPUT VOLTAGE HYSTERESIS
RIPPLE REJECTION RATIO
SHORT CIRCUIT TO GND
enp-p
tR
∆VO
∆VO_HYS
RRR
ISC
SHUTDOWN PIN
Shutdown Supply Current
Shutdown Logic Input Current
Shutdown Logic Low
Shutdown Logic High
ISHDN
ILOGIC
VINL
VINH
INITIAL ACCURACY
1
Conditions
A grade
B grade
A grade
A grade
B grade
B grade
A grade, −40°C < TA < +125°C
B grade, −40°C < TA < +125°C
Min
4.090
4.091
Typ
4.096
4.096
Max
4.102
4.101
6
0.15
5
0.12
25
9
10
25
140
120
140
300
VIN = 4.3 V to 15 V, −40°C < TA < +125°C
ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 5 V
No load
−40°C < TA < +125°C
0.1 Hz to 10 Hz
7
20
50
100
80
25
30
1000 hours
fIN = 60 kHz
VIN = 5 V
VIN = 15 V
3
500
0.8
2.4
The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period.
Rev. F | Page 5 of 20
Unit
V
V
mV
%
mV
%
ppm/°C
ppm/°C
mV
ppm/V
ppm/mA
µA
µA
µV p-p
µs
ppm
ppm
dB
mA
mA
µA
nA
V
V
ADR390/ADR391/ADR392/ADR395
ADR395 SPECIFICATIONS
Electrical characteristics, VIN = 5.3 V to 15 V, TA = 25°C, unless otherwise noted.
Table 5.
Parameter
OUTPUT VOLTAGE
TEMPERATURE COEFFICIENT
Symbol
VO
VO
VOERR
VOERR
VOERR
VOERR
TCVO
SUPPLY VOLTAGE HEADROOM
LINE REGULATION
LOAD REGULATION
QUIESCENT CURRENT
VIN − VO
∆VO/∆VIN
∆VO/∆ILOAD
IIN
VOLTAGE NOISE
TURN-ON SETTLING TIME
LONG-TERM STABILITY1
OUTPUT VOLTAGE HYSTERESIS
RIPPLE REJECTION RATIO
SHORT CIRCUIT TO GND
en p-p
tR
∆VO
∆VO_HYS
RRR
ISC
SHUTDOWN PIN
Shutdown Supply Current
Shutdown Logic Input Current
Shutdown Logic Low
Shutdown Logic High
ISHDN
ILOGIC
VINL
VINH
INITIAL ACCURACY
1
Conditions
A grade
B grade
A grade
B grade
B grade
B grade
A grade, −40°C < TA < +125°C
B grade, −40°C < TA < +125°C
Min
4.994
4.995
Typ
5.000
5.000
Max
5.006
5.005
6
0.12
5
0.10
25
9
10
25
140
120
140
300
VIN = 4.3 V to 15 V, −40°C < TA < +125°C
ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 6 V
No load
−40°C < TA < +125°C
0.1 Hz to 10 Hz
8
20
50
100
80
25
30
1, 000 hours
fIN = 60 kHz
VIN = 5 V
VIN = 15 V
3
500
0.8
2.4
The long-term stability specification is noncumulative. The drift of subsequent 1,000 hour periods is significantly lower than in the first 1,000 hour period.
Rev. F | Page 6 of 20
Unit
V
V
mV
%
mV
%
ppm/°C
ppm/°C
mV
ppm/V
ppm/mA
µA
µA
µV p-p
µs
ppm
ppm
dB
mA
mA
µA
nA
V
V
ADR390/ADR391/ADR392/ADR395
ABSOLUTE MAXIMUM RATINGS
THERMAL RESISTANCE
At 25°C, unless otherwise noted.
Table 6.
Parameter
Supply Voltage
Output Short-Circuit Duration to GND
Storage Temperature Range
Operating Temperature Range
Junction Temperature Range
Lead Temperature Range
(Soldering, 60 sec)
Rating
18 V
See derating
curves
–65°C to +125°C
–40°C to +125°C
–65°C to +125°C
300°C
θJA is specified for the worst-case conditions, that is, θJA is
specified for a device soldered in a circuit board for surfacemount packages.
Table 7. Thermal Resistance
Package Type
TSOT-23-5 (UJ-5)
θJA
230
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.
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. F | Page 7 of 20
θJC
146
Unit
°C/W
ADR390/ADR391/ADR392/ADR395
TERMINOLOGY
Temperature Coefficient
The change of output voltage with respect to operating temperature changes normalized by the output voltage at 25°C. This
parameter is expressed in ppm/°C and can be determined by the
following equation:
VO_HYS [ppm] =
VO (25°C ) – VO_TC
VO (25°C )
× 10 6
where:
VO (25°C) = VO at 25°C
VO (T2 ) – VO (T1 )
TCVO [ppm/ °C ] =
× 10 6
VO (25°C ) × (T2 – T1 )
VO_TC = VO at 25°C after a temperature cycle from + 25°C
to –40°C to +125°C and back to +25°C
where:
NOTES
VO (25°C) = VO at 25°C
Input Capacitor
Input capacitors are not required on the ADR39x. There is no
limit for the value of the capacitor used on the input, but a
1 µF to 10 µF capacitor on the input improves transient
response in applications where the supply suddenly changes.
An additional 0.1 µF in parallel also helps reduce noise
from the supply.
VO (T1) = VO at Temperature 1
VO (T2) = VO at Temperature 2
Line Regulation
The change in output voltage due to a specified change in input
voltage. This parameter accounts for the effects of self-heating.
Line regulation is expressed in either percent per volt, partsper-million per volt, or microvolts per volt change in input
voltage.
Load Regulation
The change in output voltage due to a specified change in load
current. This parameter accounts for the effects of self-heating.
Load regulation is expressed in either microvolts per milliampere, parts-per-million per milliampere, or ohms of dc
output resistance.
Long-Term Stability
Typical shift of output voltage at 25°C on a sample of parts
subjected to a test of 1,000 hours at 25°C.
Output Capacitor
The ADR39x does not require output capacitors for stability
under any load condition. An output capacitor, typically 0.1 µF,
filters out any low level noise voltage and does not affect the
operation of the part. On the other hand, the load transient
response can improve with the addition of a 1 µF to 10 µF
output capacitor in parallel. A capacitor here acts as a source of
stored energy for a sudden increase in load current. The only
parameter that degrades by adding an output capacitor is the
turn-on time, and it depends on the size of the capacitor
chosen.
150
100
∆VO = VO(t0) – VO(t1)
⎛ V (t ) – VO (t 1 )
⎞
∆VO [ppm] = ⎜⎜ O 0
× 10 6 ⎟⎟
V
(
t
)
O 0
⎝
⎠
DRIFT (ppm)
50
where:
0
–50
VO (T0) = VO at 25°C at Time 0
00419-D-002
–100
VO (T1) = VO at 25°C after 1,000 hours operation at 25°C
–150
Thermal Hysteresis
The change of output voltage after the device is cycled through
temperatures from +25°C to –40°C to +125°C and back to
+25°C. This is a typical value from a sample of parts put
through such a cycle.
VO_HYS = VO(25°C) – VO_TC
Rev. F | Page 8 of 20
0
100
200
300
400 500 600
TIME (Hours)
700
800
900
1000
Figure 2. ADR391 Typical Long-Term Drift over 1,000 Hours
ADR390/ADR391/ADR392/ADR395
TYPICAL PERFORMANCE CHARACTERISTICS
5.006
2.060
5.004
SAMPLE 3
SAMPLE 2
5.002
2.052
VOUT (V)
OUTPUT VOLTAGE (V)
2.056
SAMPLE 3
2.048
SAMPLE 2
5.000
SAMPLE 1
4.998
SAMPLE 1
2.044
–5
30
65
TEMPERATURE (°C)
100
4.994
–40
125
Figure 3. ADR390 Output Voltage vs. Temperature
00419-D-006
00419-D-003
2.040
–40
4.996
–5
100
30
65
TEMPERATURE (°C)
125
Figure 6. ADR395 Output Voltage vs. Temperature
140
2.506
SAMPLE 2
+125°C
2.504
120
SUPPLY CURRENT (µA)
SAMPLE 1
SAMPLE 3
2.500
2.498
+85°C
–40°C
80
00419-D-004
2.494
–40
–5
30
65
TEMPERATURE (°C)
100
40
2.5
125
Figure 4. ADR391 Output Voltage vs. Temperature
00419-D-007
60
2.496
5.0
7.5
10.0
INPUT VOLTAGE (V)
12.5
15.0
Figure 7. ADR390 Supply Current vs. Input Voltage
4.100
140
4.098
120
SUPPLY CURRENT (µA)
SAMPLE 3
4.096
SAMPLE 2
4.094
SAMPLE 1
4.092
+85°C
100
+25°C
–40°C
80
60
4.090
4.088
–40
00419-D-005
VOUT (V)
+25°C
100
0
40
TEMPERATURE (°C)
80
40
2.5
125
Figure 5. ADR392 Output Voltage vs. Temperature
00419-D-008
VOUT (V)
2.502
5.0
7.5
10.0
INPUT VOLTAGE (V)
12.5
Figure 8. ADR391 Supply Current vs. Input Voltage
Rev. F | Page 9 of 20
15.0
ADR390/ADR391/ADR392/ADR395
140
180
IL= 0mA TO 5mA
100
+25°C
–40°C
80
00419-D-009
60
40
5
7
9
11
INPUT VOLTAGE (V)
VIN = 5.0V
140
VIN = 3.0V
120
100
80
–40
15
13
160
Figure 9. ADR392 Supply Current vs. Input Voltage
00419-D-012
SUPPLY CURRENT (µA)
120
LOAD REGULATION (ppm/mA)
+125°C
–10
20
50
TEMPERATURE (°C)
80
110
125
Figure 12. ADR391 Load Regulation vs. Temperature
90
140
IL= 0mA TO 5mA
–40°C
80
40
5.5
00419-D-010
60
7.0
8.5
11.5
10.0
INPUT VOLTAGE (V)
13.0
VIN = 7.5V
70
VIN = 5V
60
50
40
–40
14.5
–5
30
65
TEMPERATURE (°C)
125
100
Figure 13. ADR392 Load Regulation vs. Temperature
Figure 10. ADR395 Supply Current vs. Input Voltage
80
120
IL= 0mA TO 5mA
IL= 0mA TO 5mA
LOAD REGULATION (ppm/mA)
100
80
60
VIN = 3.0V
VIN = 5.0V
40
20
0
–40
00419-D-011
LOAD REGULATION (ppm/mA)
00419-D-013
+25°C
100
80
–10
20
50
TEMPERATURE (°C)
80
110
70
VIN = 7.5V
VIN = 5V
60
50
40
30
–40
125
Figure 11. ADR390 Load Regulation vs. Temperature
00419-D-014
SUPPLY CURRENT (µA)
LOAD REGULATION (ppm/mA)
+125°C
120
–5
30
65
TEMPERATURE (°C)
100
Figure 14. ADR395 Load Regulation vs. Temperature
Rev. F | Page 10 of 20
125
ADR390/ADR391/ADR392/ADR395
25
14
LINE REGULATION (ppm/V)
LINE REGULATION (ppm/V)
12
20
15
10
10
VIN = 5.3V TO 15V
8
6
4
–10
20
50
TEMPERATURE (°C)
80
110
2
00419-D-018
0
–40
00419-D-015
5
0
–40
125
Figure 15. ADR390 Line Regulation vs. Temperature
–5
30
65
TEMPERATURE (°C)
125
100
Figure 18. ADR395 Line Regulation vs. Temperature
25
3.0
20
2.8
VIN_MIN (V)
15
10
2.6
–40°C
2.4
+25°C
+85°C
2.2
0
–40
00419-D-016
5
–10
20
50
TEMPERATURE (°C)
80
110
2.0
125
00419-D-019
LINE REGULATION (ppm/V)
+125°C
0
1
2
3
LOAD CURRENT (mA)
4
5
Figure 19. ADR390 Minimum Input Voltage vs. Load Current
Figure 16. ADR391 Line Regulation vs. Temperature
14
3.6
+125°C
12
+85°C
VIN_MIN (V)
10
8
VIN = 4.4V TO 15V
6
3.2
+25°C
3.0
–40°C
4
0
–40
–5
30
65
TEMPERATURE (°C)
100
2.6
125
00419-D-020
2.8
2
00419-D-017
LINE REGULATION (ppm/V)
3.4
0
1
2
3
LOAD CURRENT (mA)
4
Figure 20. ADR391 Minimum Input Voltage vs. Load Current
Figure 17. ADR392 Line Regulation vs. Temperature
Rev. F | Page 11 of 20
5
ADR390/ADR391/ADR392/ADR395
4.8
70
TEMPERATURE: +25°C
–40°C
+125°C
+25°C
60
+125°C
4.6
4.4
FREQUENCY
VIN_MIN (V)
50
+25°C
–40°C
4.2
40
30
20
4.0
3.8
0
1
4
2
3
LOAD CURRENT (mA)
0
–0.56
5
Figure 21. ADR392 Minimum Input Voltage vs. Load Current
1k
VOLTAGE NOISE DENSITY (nV/ Hz)
5.8
VIN_MIN (V)
+25°C
–40°C
5.0
00419-D-022
4.8
4.6
0
1
2
3
LOAD CURRENT (mA)
0.34
VIN = 5V
ADR390
100
10
1k
100
FREQUENCY (Hz)
10k
Figure 25. Voltage Noise Density vs. Frequency
Figure 22. ADR395 Minimum Input Voltage vs. Load Current
60
0.19
ADR391
5
4
–0.11
–0.26
0.04
VOUT DEVIATION (mV)
00419-D-025
+125°C
5.6
5.2
–0.41
Figure 24. ADR391 VOUT Hysteresis Distribution
6.0
5.4
00419-D-024
00419-D-021
10
0
TEMPERATURE: +25°C
–40°C
+125°C
+25°C
0
50
VOLTAGE (2µV/DIV)
0
0
0
30
0
20
0
–0.24 –0.18 –0.12 –0.06
0
0.06 0.12
VOUT DEVIATION (mV)
0.18
0.24
00419-D-026
0
10
00419-D-023
FREQUENCY
40
0
0
0.30
TIME (1 Sec/DIV)
Figure 23. ADR390 VOUT Hysteresis Distribution
Figure 26. ADR391 Typical Voltage Noise 0.1 Hz to 10 Hz
Rev. F | Page 12 of 20
ADR390/ADR391/ADR392/ADR395
CL = 0nF
VLOAD ON
LOAD OFF
00419-D-030
VOLTAGE (1V/DIV)
VOLTAGE (100µV/DIV)
VOUT
TIME (200µs/DIV)
TIME (10µs/DIV)
Figure 27. ADR391 Voltage Noise 10 Hz to 10 kHz
Figure 30. ADR391 Load Transient Response
CL = 1nF
CBYPASS = 0µF
VOUT
LINE
INTERRUPTION
VOLTAGE
VOLTAGE (1V/DIV)
0.5V/DIV
VOUT
VLOAD ON
00419-D-028
00419-D-031
1V/DIV
LOAD OFF
TIME (200µs/DIV)
TIME (10µs/DIV)
Figure 28. ADR391 Line Transient Response
Figure 31. ADR391 Load Transient Response
CBYPASS = 0.1µF
CL = 100nF
VOUT
VOLTAGE
VOLTAGE (1V/DIV)
0.5V/DIV
LINE
INTERRUPTION
VOUT
VLOAD ON
00419-D-032
00419-D-029
1V/DIV
LOAD OFF
TIME (10µs/DIV)
TIME (200µs/DIV)
Figure 29. ADR391 Line Transient Response
Figure 32. ADR391 Load Transient Response
Rev. F | Page 13 of 20
ADR390/ADR391/ADR392/ADR395
RL = 500Ω
VIN = 15V
5V/DIV
2V/DIV
VOLTAGE
VOLTAGE
VOUT
VIN
2V/DIV
VOUT
5V/DIV
00419-D-036
00419-D-033
VIN
TIME (20µs/DIV)
TIME (200µs/DIV)
Figure 33. ADR391 Turn-On Response Time at 15 V
Figure 36. ADR391 Turn-On/Turn-Off Response at 5 V
VIN = 15V
VIN
RL = 500Ω
CL = 100nF
5V/DIV
2V/DIV
VOLTAGE (5V/DIV)
VOLTAGE
5V/DIV
VIN
00419-D-037
2V/DIV
00419-D-034
VOUT
VOUT
TIME (40µs/DIV)
TIME (200µs/DIV)
Figure 37. ADR391 Turn-On/Turn-Off Response at 5 V
Figure 34. ADR391 Turn-Off Response at 15 V
80
CBYPASS = 0.1µF
60
40
RIPPLE REJECTION (dB)
2V/DIV
VOLTAGE
VOUT
5V/DIV
0
–20
–40
–60
00419-D-038
–80
00419-D-035
VIN
20
–100
–120
10
TIME (200µs/DIV)
Figure 35. ADR391 Turn-On/Turn-Off Response at 5 V
100
1k
10k
FREQUENCY (Hz)
100k
Figure 38. Ripple Rejection vs. Frequency
Rev. F | Page 14 of 20
1M
ADR390/ADR391/ADR392/ADR395
100
90
70
60
CL = 0µF
50
40
30
20
CL = 1µF
10
0
10
100
1k
10k
FREQUENCY (Hz)
CL = 0.1µF
100k
00419-D-039
OUTPUT IMPEDANCE (Ω)
80
1M
Figure 39. Output Impedance vs. Frequency
Rev. F | Page 15 of 20
ADR390/ADR391/ADR392/ADR395
THEORY OF OPERATION
Band gap references are the high performance solution for low
supply voltage and low power voltage reference applications,
and the ADR390/ADR391/ADR392/ADR395 are no exception.
The uniqueness of these devices lies in the architecture. As
shown in Figure 40, the ideal zero TC band gap voltage is
referenced to the output, not to ground. Therefore, if noise
exists on the ground line, it is greatly attenuated on VOUT. The
band gap cell consists of the PNP pair, Q51 and Q52, running at
unequal current densities. The difference in VBE results in a
voltage with a positive TC, which is amplified by a ratio of
2×
DEVICE POWER DISSIPATION CONSIDERATIONS
The ADR390/ADR391/ADR392/ADR395 are capable of delivering load currents to 5 mA, with an input voltage that ranges
from 2.8 V (ADR391 only) to 15 V. When these devices are
used in applications with large input voltages, care should be
taken to avoid exceeding the specified maximum power
dissipation or junction temperature because it could result in
premature device failure. The following formula should be used
to calcu-late a device’s maximum junction temperature or
dissipation:
R58
R54
PD =
This PTAT voltage, combined with VBEs of Q51 and Q52,
produces a stable band gap voltage.
Reduction in the band gap curvature is performed by the ratio
of the resistors R44 and R59, one of which is linearly
temperature dependent. Precision laser trimming and other
patented circuit techniques are used to further enhance the
drift performance.
VIN
Q1
VOUT (FORCE)
VOUT (SENSE)
R59
R44
SHUTDOWN MODE OPERATION
The ADR390/ADR391/ADR392/ADR395 include a shutdown
feature that is TTL/CMOS level compatible. A logic low or a
zero volt condition on the SHDN pin is required to turn the
devices off. During shutdown, the output of the reference
becomes a high impedance state, where its potential would then
be determined by external circuitry. If the shutdown feature is
not used, the SHDN pin should be connected to VIN (Pin 2).
R49
R54
Q51
R53
R48
R61
GND
00419-D-040
Q52
R60
θJA
In this equation, TJ and TA are, respectively, the junction and
ambient temperatures. PD is the device power dissipation, and
θJA is the device package thermal resistance.
R58
SHDN
TJ – TA
Figure 40. Simplified Schematic
Rev. F | Page 16 of 20
ADR390/ADR391/ADR392/ADR395
APPLICATIONS
BASIC VOLTAGE REFERENCE CONNECTION
The circuit shown in Figure 41 illustrates the basic configuration
for the ADR39x family. Decoupling capacitors are not required
for circuit stability. The ADR39x family is capable of driving
capacitive loads from 0 µF to 10 µF. However, a 0.1 µF ceramic
output capacitor is recommended to absorb and deliver the
charge, as required by a dynamic load.
SHUTDOWN
GND
SHDN
ADR39x
INPUT
CB
*
VIN
0.1µF
*
CB
*NOT REQUIRED
OUTPUT
0.1µF
00419-D-041
VOUT(S) VOUT(F)
Figure 41. Basic Configuration for the ADR39x Family
Stacking Reference ICs for Arbitrary Outputs
Some applications may require two reference voltage sources,
which are a combined sum of standard outputs. Figure 42 shows
how this stacked output reference can be implemented.
OUTPUT TABLE
U1/U2
2.048
2.5
4.096
5
4.096
5.0
8.192
10
A negative reference can be easily generated by adding an A1 op
amp and is configured as shown in Figure 43. VOUTF and VOUTS
are at virtual ground and, therefore, the negative reference can
be taken directly from the output of the op amp. The op amp
must be dual-supply, low offset, and rail-to-rail if the negative
supply voltage is close to the reference output.
VIN
2
U2
VIN
1
VOUT(F)
SHDN
C2
0.1µF
VOUT(S)
4
While this concept is simple, a precaution is required. Since the
lower reference circuit must sink a small bias current from U2
plus the base current from the series PNP output transistor in
U2, either the external load of U1 or R1 must provide a path for
this current. If the U1 minimum load is not well defined, the R1
resistor should be used and set to a value that will conservatively
pass 600 µA of current with the applicable VOUT1 across it. Note
that the two U1 and U2 reference circuits are treated locally as
macrocells; each has its own bypasses at input and output for
best stability. Both U1 and U2 in this circuit can source dc
currents up to their full rating. The minimum input voltage,
VIN, is determined by the sum of the outputs, VOUT2, plus the
dropout voltage of U2.
A Negative Precision Reference without Precision
Resistors
VOUT1 (V) VOUT2 (V)
ADR390/ADR390
ADR391/ADR391
ADR392/ADR392
ADR395/ADR395
Two reference ICs are used, fed from an unregulated input, VIN.
The outputs of the individual ICs are simply connected in
series, which provides two output voltages, VOUT1 and VOUT2.
VOUT1 is the terminal voltage of U1, while VOUT2 is the sum of
this voltage and the terminal voltage of U2. U1 and U2 are
simply chosen for the two voltages that supply the required
outputs (see the Output Table in Figure 42). For example, if
both U1 and U2 are ADR391s, VOUT1 is 2.5 V and VOUT2 is 5.0 V.
VOUT2
+VDD
3
GND
2
5
VIN
4 V
OUT(F)
U1
2
VIN
VOUT(F)
SHDN
VOUT(S)
4
VOUT1
1
GND
5
3
GND
–VREF
A1
00419-D-042
5
SHDN
–VDD
Figure 42. Stacking Voltage References with the
ADR390/ADR391/ADR392/ADR395
Figure 43. Negative Reference
Rev. F | Page 17 of 20
00419-D-043
1
C2
0.1µF
3 V
OUT(S)
ADR390/ADR391/ADR392/ADR395
Many times in low power applications, the need arises for a
precision current source that can operate on low supply voltages. ADR390/ADR391/ADR392/ADR395 can be configured
as a precision current source. As shown in Figure 45, the circuit
configuration is a floating current source with a grounded load.
The reference’s output voltage is bootstrapped across RSET,
which sets the output current into the load. With this
configuration, circuit precision is maintained for load currents
in the range from the reference’s supply current, typically 90 µA
to approximately 5 mA.
The transistor Q2 protects Q1 during short-circuit limit faults
by robbing its base drive. The maximum current is
ILMAX ≈ 0.6 V/RS
VIN
R1
4.7kΩ
U1
SHDN
GND
VIN
VOUT (FORCE)
VOUT (SENSE)
Q1
Q2N4921
Q2
Q2N2222
RS
ADR39x
VIN
RL
SHDN
VOUT
IL
00419-D-045
General-Purpose Current Source
Figure 45. ADR39x for High Power Performance with Current Limit
ADR39x
VIN
ISET
VOUT
R1
0.1µF
A similar circuit function can also be achieved with the
Darlington transistor configuration, as shown in Figure 46.
R1
GND
ISY (ISET)
VIN
P1
U1
SHDN
GND
VIN
IOUT = ISET + ISY (ISET)
Q2N2222
VOUT (FORCE)
00419-D-044
RL
R1
4.7kΩ
Q1
Q2
VOUT (SENSE)
ADR39x
Figure 44. A General-Purpose Current Source
Q2N4921
RS
RL
High Power Performance with Current Limit
In some cases, the user may want higher output current
delivered to a load and still achieve better than 0.5% accuracy
out of the ADR39x. The accuracy for a reference is normally
specified on the data sheet with no load. However, the output
voltage changes with load current.
The circuit shown in Figure 45 provides high current without
compromising the accuracy of the ADR39x. The series pass
transistor Q1 provides up to 1 A load current. The ADR39x
delivers only the base drive to Q1 through the force pin. The
sense pin of the ADR39x is a regulated output and is connected
to the load.
Rev. F | Page 18 of 20
Figure 46. ADR39x for High Output Current
with Darlington Drive Configuration
00419-D-046
RSET
ISY
ADJUST
ADR390/ADR391/ADR392/ADR395
OUTLINE DIMENSIONS
2.90 BSC
5
4
2.80 BSC
1.60 BSC
1
2
3
PIN 1
0.95 BSC
1.90
BSC
0.90
0.87
0.84
1.00 MAX
0.10 MAX
0.50
0.30
SEATING
PLANE
8°
4°
0.20
0.08
0.60
0.45
0.30
COMPLIANT TO JEDEC STANDARDS MO-193AB
Figure 47. 5-Lead Thin Small Outline Transistor Package [TSOT]
(UJ-5)
Dimensions shown in millimeters
ORDERING GUIDE
Models
ADR390AUJZ-REEL71
ADR390AUJZ-R21
ADR390BUJZ-REEL71
ADR390BUJZ-R21
ADR391AUJZ-REEL71
ADR391AUJZ-R21
ADR391BUJZ-REEL71
ADR391BUJZ-R21
ADR392AUJZ-REEL71
ADR392AUJZ-R21
ADR392BUJZ-REEL71
ADR392BUJZ-R21
ADR395AUJZ-REEL71
ADR395AUJZ-R21
ADR395BUJZ-REEL71
ADR395BUJZ-R21
1
Output
Voltage
(VO)
2.048
2.048
2.048
2.048
2.5
2.5
2.5
2.5
4.096
4.096
4.096
4.096
5.0
5.0
5.0
5.0
Initial
Accuracy
(mV) (%)
6
0.29
6
0.29
4
0.19
4
0.19
6
0.24
6
0.24
4
0.16
4
0.16
6
0.15
6
0.15
5
0.12
5
0.12
6
0.12
6
0.12
5
0.10
5
0.10
Temperature
Coefficient
(ppm/°C)
25
25
9
9
25
25
9
9
25
25
9
9
25
25
9
9
Package
Description
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
TSOT
Z = Pb-free part.
Rev. F | Page 19 of 20
Package
Option
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
UJ-5
Branding
R0A
R0A
R0B
R0B
R1A
R1A
R1B
R1B
RCA
RCA
RCB
RCB
RDA
RDA
RDB
RDB
Number
of Parts
per Reel
3,000
250
3,000
250
3,000
250
3,000
250
3,000
250
3,000
250
3,000
250
3,000
250
Temperature
Range
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
ADR390/ADR391/ADR392/ADR395
NOTES
© 2005 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
C00419–0–5/05(F)
Rev. F | Page 20 of 20
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