Precision, Ultralow Noise, RRIO,
Zero-Drift Op Amp
ADA4528-1/ADA4528-2
Data Sheet
PIN CONNECTION DIAGRAMS
Low offset voltage: 2.5 µV maximum
Low offset voltage drift: 0.015 μV/°C maximum
Low noise
5.6 nV/√Hz at f = 1 kHz, AV = +100
97 nV p-p at f = 0.1 Hz to 10 Hz, AV = +100
Open-loop gain: 130 dB minimum
CMRR: 135 dB minimum
PSRR: 130 dB minimum
Unity-gain crossover: 4 MHz
Gain bandwidth product: 3 MHz at AV = 100
−3 dB closed-loop bandwidth: 6.2 MHz
Single-supply operation: 2.2 V to 5.5 V
Dual-supply operation: ±1.1 V to ±2.75 V
Rail-to-rail input and output
Unity-gain stable
NIC 1
ADA4528-1
+IN 3
TOP VIEW
(Not to Scale)
V– 4
8
NIC
7
V+
6
OUT
5
NIC
NOTES
1. NIC = NO INTERNAL CONNECTION.
Figure 1. ADA4528-1 Pin Configuration, 8-Lead MSOP
NIC 1
8 NIC
–IN 2
ADA4528-1
+IN 3
TOP VIEW
(Not to Scale)
V– 4
7 V+
6 OUT
09437-102
5 NIC
NOTES
1. NIC = NO INTERNAL CONNECTION.
2. CONNECT THE EXPOSED PAD TO
V– OR LEAVE IT UNCONNECTED.
APPLICATIONS
Figure 2. ADA4528-1 Pin Configuration, 8-Lead LFCSP
Thermocouple/thermopile
Load cell and bridge transducers
Precision instrumentation
Electronic scales
Medical instrumentation
Handheld test equipment
For ADA4528-2 pin connections and for more information about
the pin connections for these products, see the Pin Configurations
and Function Descriptions section.
The ADA4528-1/ADA4528-2 are ultralow noise, zero-drift
operational amplifiers featuring rail-to-rail input and output
swing. With an offset voltage of 2.5 μV, offset voltage drift of
0.015 μV/°C, and typical noise of 97 nV p-p (0.1 Hz to 10 Hz,
AV = +100), the ADA4528-1/ADA4528-2 are well suited for
applications in which error sources cannot be tolerated.
The ADA4528-1/ADA4528-2 have a wide operating supply range
of 2.2 V to 5.5 V, high gain, and excellent CMRR and PSRR
specifications, which make it ideal for applications that require
precision amplification of low level signals, such as position and
pressure sensors, strain gages, and medical instrumentation.
The ADA4528-1/ADA4528-2 are specified over the extended
industrial temperature range (−40°C to +125°C). The ADA4528-1
is available in 8-lead MSOP and 8-lead LFCSP packages. The
ADA4528-2 is available in an 8-lead MSOP package.
For more information about the ADA4528-1/ADA4528-2,
see the AN-1114 Application Note, Lowest Noise Zero-Drift
Amplifier Has 5.6 nV/√Hz Voltage Noise Density.
VSY = 5V
AV = 1
VCM = VSY/2
10
1
1
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
10M
09437-063
VOLTAGE NOISE DENSITY (nV/√Hz)
100
GENERAL DESCRIPTION
Figure 3. Voltage Noise Density vs. Frequency
Table 1. Analog Devices, Inc., Zero-Drift Op Amp Portfolio 1
Low
Ultralow Micropower Power
Type Noise
(<20 µA)
(<1 mA)
Single ADA4528-1 ADA4051-1 AD8628
AD8538
Dual
ADA4528-2 ADA4051-2 AD8629
AD8539
Quad
AD8630
1
Rev. C
–IN 2
09437-001
FEATURES
16 V
Operating
Voltage
AD8638
30 V
Operating
Voltage
ADA4638-1
AD8639
See www.analog.com for the latest selection of zero-drift operational amplifiers.
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ADA4528-1/ADA4528-2
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Pin Configurations and Function Descriptions ............................8
Applications ....................................................................................... 1
Typical Performance Characteristics ........................................... 10
General Description ......................................................................... 1
Applications Information .............................................................. 19
Pin Connection Diagrams ............................................................... 1
Input Protection ......................................................................... 19
Revision History ............................................................................... 2
Rail-to-Rail Input and Output .................................................. 19
Specifications..................................................................................... 3
Noise Considerations ................................................................. 19
Electrical Characteristics—2.5 V Operation ............................ 3
Comparator Operation .............................................................. 21
Electrical Characteristics—5 V Operation................................ 5
Printed Circuit Board Layout ................................................... 22
Absolute Maximum Ratings ............................................................ 7
Outline Dimensions ....................................................................... 23
Thermal Resistance ...................................................................... 7
Ordering Guide .......................................................................... 23
ESD Caution .................................................................................. 7
REVISION HISTORY
9/12—Rev. B to Rev. C
Changes to Features Section............................................................ 1
Added Comparator Operation Section ....................................... 21
Added Figure 65 to Figure 69; Renumbered Sequentially ........ 21
7/12—Rev. A to Rev. B
Added ADA4528-2 ............................................................. Universal
Changes to Features Section, Figure 1, Figure 2, and Table 1 .... 1
Added Pin Connection Diagrams Section and Figure 3;
Renumbered Sequentially................................................................ 1
Changes to Table 2 ............................................................................ 3
Changes to Table 3 ............................................................................ 5
Change to Endnote 1 of Table 4 and Thermal Resistance
Section ................................................................................................ 7
Added Pin Configurations and Function Descriptions Section,
Figure 4, Figure 5, and Table 6 ........................................................ 8
Added Figure 6 and Table 7............................................................. 9
Changes to Input Protection Section ........................................... 19
Changes to Source Resistance Section and
Caption of Figure 63 ....................................................................... 20
Changes to Residual Voltage Ripple Section and
Caption of Figure 64....................................................................... 21
Changes to Ordering Guide .......................................................... 22
9/11—Rev. 0 to Rev. A
Added 8-Lead LFCSP_WD Package ................................ Universal
Changes to General Description Section ......................................1
Added Figure 2; Renumbered Sequentially ...................................1
Changes to Offset Voltage, Offset Voltage Drift, Power Supply
Rejection Ratio, and Settling Time to 0.1% Parameters, Table 2 ...3
Changes to Thermal Resistance Section and Table 5 ...................5
Changes to Figure 41 and Figure 44 ............................................ 12
Changes to Figure 45 and Figure 48 ............................................ 13
Updated Outline Dimensions ....................................................... 18
Changes to Ordering Guide .......................................................... 18
1/11—Revision 0: Initial Version
Rev. C | Page 2 of 24
Data Sheet
ADA4528-1/ADA4528-2
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS—2.5 V OPERATION
VSY = 2.5 V, VCM = VSY/2, TA = 25°C, unless otherwise specified.
Table 2.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Test Conditions/Comments
VOS
VCM = 0 V to 2.5 V
−40°C ≤ TA ≤ +125°C, MSOP package
−40°C ≤ TA ≤ +125°C, LFCSP package
−40°C ≤ TA ≤ +125°C, MSOP package
−40°C ≤ TA ≤ +125°C, LFCSP package
Offset Voltage Drift
ΔVOS/ΔT
Input Bias Current
IB
Min
Typ
Max
Unit
0.3
2.5
4
4.3
0.015
0.018
400
600
800
1
2.5
μV
μV
μV
μV/°C
μV/°C
pA
pA
pA
nA
V
dB
dB
dB
dB
dB
dB
dB
dB
0.002
220
−40°C ≤ TA ≤ +125°C
Input Offset Current
IOS
440
−40°C ≤ TA ≤ +125°C
Input Voltage Range
Common-Mode Rejection Ratio
CMRR
Open-Loop Gain
AVO
ADA4528-1
ADA4528-2
Input Resistance
Differential Mode
Common Mode
Input Capacitance
Differential Mode
Common Mode
OUTPUT CHARACTERISTICS
Output Voltage High
Output Voltage Low
Short-Circuit Current
Closed-Loop Output Impedance
POWER SUPPLY
Power Supply Rejection Ratio
Supply Current per Amplifier
DYNAMIC PERFORMANCE
Slew Rate
Settling Time to 0.1%
Unity-Gain Crossover
Phase Margin
Gain Bandwidth Product
−3 dB Closed-Loop Bandwidth
Overload Recovery Time
VCM = 0 V to 2.5 V
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ, VO = 0.1 V to 2.4 V
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ, VO = 0.1 V to 2.4 V
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ, VO = 0.1 V to 2.4 V
−40°C ≤ TA ≤ +125°C
0
135
116
130
126
125
121
122
119
158
140
132
132
RINDM
RINCM
225
1
kΩ
GΩ
CINDM
CINCM
15
30
pF
pF
2.495
V
V
V
V
mV
mV
mV
mV
mA
Ω
VOH
VOL
ISC
ZOUT
PSRR
ISY
SR
tS
UGC
ΦM
GBP
f−3dB
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ to VCM
−40°C ≤ TA ≤ +125°C
2.49
2.485
2.46
2.44
5
20
RL = 10 kΩ, CL = 100 pF, AV = +1
VIN = 1.5 V step, RL = 10 kΩ, CL = 100 pF, AV = −1
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +1
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +1
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +100
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +1
RL = 10 kΩ, CL = 100 pF, AV = −10
Rev. C | Page 3 of 24
10
15
40
60
±30
0.1
f = 1 kHz, AV = +10
VSY = 2.2 V to 5.5 V
−40°C ≤ TA ≤ +125°C
IO = 0 mA
−40°C ≤ TA ≤ +125°C
2.48
130
127
150
1.4
0.45
7
4
57
3
6.2
50
1.7
2.1
dB
dB
mA
mA
V/μs
µs
MHz
Degrees
MHz
MHz
μs
ADA4528-1/ADA4528-2
Parameter
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise
Current Noise Density
Data Sheet
Symbol
Test Conditions/Comments
en p-p
en
f = 0.1 Hz to 10 Hz, AV = +100
f = 1 kHz, AV = +100
f = 1 kHz, AV = +100, VCM = 2.0 V
f = 0.1 Hz to 10 Hz, AV = +100
f = 1 kHz, AV = +100
in p-p
in
Rev. C | Page 4 of 24
Min
Typ
97
5.6
5.5
10
0.7
Max
Unit
nV p-p
nV/√Hz
nV/√Hz
pA p-p
pA/√Hz
Data Sheet
ADA4528-1/ADA4528-2
ELECTRICAL CHARACTERISTICS—5 V OPERATION
VSY = 5 V, VCM = VSY/2, TA = 25°C, unless otherwise specified.
Table 3.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Test Conditions/Comments
VOS
Offset Voltage Drift
Input Bias Current
ADA4528-1
ΔVOS/ΔT
IB
VCM = 0 V to 5 V
−40°C ≤ TA ≤ +125°C
−40°C ≤ TA ≤ +125°C
Min
Typ
Max
Unit
0.3
2.5
4
0.015
μV
μV
μV/°C
200
300
250
350
pA
pA
pA
pA
400
500
500
600
5
pA
pA
pA
pA
V
dB
dB
dB
dB
dB
dB
0.002
90
−40°C ≤ TA ≤ +125°C
ADA4528-2
125
−40°C ≤ TA ≤ +125°C
Input Offset Current
ADA4528-1
IOS
180
−40°C ≤ TA ≤ +125°C
ADA4528-2
250
−40°C ≤ TA ≤ +125°C
Input Voltage Range
Common-Mode Rejection Ratio
CMRR
Open-Loop Gain
AVO
Input Resistance
Differential Mode
Common Mode
Input Capacitance
Differential Mode
Common Mode
OUTPUT CHARACTERISTICS
Output Voltage High
Output Voltage Low
Short-Circuit Current
Closed-Loop Output Impedance
POWER SUPPLY
Power Supply Rejection Ratio
Supply Current per Amplifier
DYNAMIC PERFORMANCE
Slew Rate
Settling Time to 0.1%
Unity-Gain Crossover
Phase Margin
Gain Bandwidth Product
−3 dB Closed-Loop Bandwidth
Overload Recovery Time
VCM = 0 V to 5 V
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ, VO = 0.1 V to 4.9 V
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ, VO = 0.1 V to 4.9 V
−40°C ≤ TA ≤ +125°C
0
137
122
127
125
121
120
160
139
131
RINDM
RINCM
190
1
kΩ
GΩ
CINDM
CINCM
16.5
33
pF
pF
4.995
V
V
V
V
mV
mV
mV
mV
mA
Ω
VOH
VOL
ISC
ZOUT
PSRR
ISY
SR
tS
UGC
ΦM
GBP
f−3dB
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 2 kΩ to VCM
−40°C ≤ TA ≤ +125°C
4.99
4.98
4.96
4.94
5
20
RL = 10 kΩ, CL = 100 pF, AV = +1
VIN = 4 V step, RL = 10 kΩ, CL = 100 pF, AV = −1
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +1
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +1
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +100
VIN = 10 mV p-p, RL = 10 kΩ, CL = 100 pF, AV = +1
RL = 10 kΩ, CL = 100 pF, AV = −10
Rev. C | Page 5 of 24
10
20
40
60
±40
0.1
f = 1 kHz, AV = +10
VSY = 2.2 V to 5.5 V
−40°C ≤ TA ≤ +125°C
IO = 0 mA
−40°C ≤ TA ≤ +125°C
4.98
130
127
150
1.5
0.5
10
4
57
3.4
6.5
50
1.8
2.2
dB
dB
mA
mA
V/μs
µs
MHz
Degrees
MHz
MHz
μs
ADA4528-1/ADA4528-2
Parameter
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise
Current Noise Density
Data Sheet
Symbol
Test Conditions/Comments
en p-p
en
f = 0.1 Hz to 10 Hz, AV = +100
f = 1 kHz, AV = +100
f = 1 kHz, AV = +100, VCM = 4.5 V
f = 0.1 Hz to 10 Hz, AV = +100
f = 1 kHz, AV = +100
in p-p
in
Rev. C | Page 6 of 24
Min
Typ
99
5.9
5.3
10
0.5
Max
Unit
nV p-p
nV/√Hz
nV/√Hz
pA p-p
pA/√Hz
Data Sheet
ADA4528-1/ADA4528-2
ABSOLUTE MAXIMUM RATINGS
THERMAL RESISTANCE
Table 4.
Parameter
Supply Voltage
Input Voltage
Input Current1
Differential Input Voltage
Output Short-Circuit Duration to GND
Storage Temperature Range
Operating Temperature Range
Junction Temperature Range
Lead Temperature (Soldering, 60 sec)
1
Rating
6V
±VSY ± 0.3 V
±10 mA
±VSY
Indefinite
−65°C to +150°C
−40°C to +125°C
−65°C to +150°C
300°C
θJA is specified for the worst-case conditions, that is, a device
soldered in a circuit board for surface-mount packages using a
4-layer JEDEC board. The exposed pad of the LFCSP package is
soldered to the board.
Table 5. Thermal Resistance
Package Type
8-Lead MSOP (RM-8)
8-Lead LFCSP (CP-8-12)
The input pins have clamp diodes to the power supply pins. Limit the input
current to 10 mA or less whenever input signals exceed the power supply
rail by 0.3 V.
ESD CAUTION
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.
Rev. C | Page 7 of 24
θJA
142
80
θJC
45
14
Unit
°C/W
°C/W
ADA4528-1/ADA4528-2
Data Sheet
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
NIC 1
ADA4528-1
+IN 3
TOP VIEW
(Not to Scale)
V– 4
NIC
7
V+
6
OUT
5
NIC
NOTES
1. NIC = NO INTERNAL CONNECTION.
8 NIC
–IN 2
ADA4528-1
+IN 3
TOP VIEW
(Not to Scale)
V– 4
5 NIC
Figure 5. ADA4528-1 Pin Configuration, 8-Lead LFCSP
Table 6. ADA4528-1 Pin Function Descriptions
Mnemonic
NIC
−IN
+IN
V−
OUT
V+
EPAD
6 OUT
NOTES
1. NIC = NO INTERNAL CONNECTION.
2. CONNECT THE EXPOSED PAD TO
V– OR LEAVE IT UNCONNECTED.
Figure 4. ADA4528-1 Pin Configuration, 8-Lead MSOP
Pin No.
1, 5, 8
2
3
4
6
7
7 V+
09437-102
–IN 2
8
09437-001
NIC 1
Description
No Internal Connection.
Inverting Input.
Noninverting Input.
Negative Supply Voltage.
Output.
Positive Supply Voltage.
Exposed Pad (LFCSP Only). Connect the exposed pad to V− or leave it unconnected.
Rev. C | Page 8 of 24
ADA4528-1/ADA4528-2
OUT A 1
–IN A 2
ADA4528-2
+IN A 3
TOP VIEW
(Not to Scale)
V–
4
8
V+
7
OUT B
6
–IN B
5
+IN B
09437-103
Data Sheet
Figure 6. ADA4528-2 Pin Configuration, 8-Lead MSOP
Table 7. ADA4528-2 Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7
8
Mnemonic
OUT A
−IN A
+IN A
V−
+IN B
−IN B
OUT B
V+
Description
Output, Channel A.
Inverting Input, Channel A.
Noninverting Input, Channel A.
Negative Supply Voltage.
Noninverting Input, Channel B.
Inverting Input, Channel B.
Output, Channel B.
Positive Supply Voltage.
Rev. C | Page 9 of 24
ADA4528-1/ADA4528-2
Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
TA = 25°C, unless otherwise noted.
100
100
VSY = 2.5V
VCM = VSY/2
90
80
70
60
50
40
30
70
60
50
40
30
20
20
10
10
–0.8
–0.6
–0.4
–0.2
0.2
0
VOS (µV)
0.4
0.6
0.8
1.0
0
–1.0
09437-002
0
–1.0
Figure 7. Input Offset Voltage Distribution
–0.6
–0.2
0
0.2
VOS (µV)
0.4
0.6
0.8
1.0
60
VSY = 2.5V
VCM = VSY/2
VSY = 5V
VCM = VSY/2
50
NUMBER OF AMPLIFIERS
50
40
30
20
10
40
30
20
0
3
6
9
12
09437-006
09437-003
10
0
0
15
0
3
TCVOS (nV/°C)
6
9
12
15
TCVOS (nV/°C)
Figure 8. Input Offset Voltage Drift Distribution
Figure 11. Input Offset Voltage Drift Distribution
1.0
1.0
VSY = 5V
VSY = 2.5V
0.8
0.6
0.6
0.4
0.4
0.2
0.2
0
–0.2
0
–0.2
–0.4
–0.4
–0.6
–0.6
–0.8
–0.8
–1.0
0
0.5
1.5
1.0
2.0
2.5
VCM (V)
Figure 9. Input Offset Voltage vs. Common-Mode Voltage
–1.0
0
1
3
2
4
VCM (V)
Figure 12. Input Offset Voltage vs. Common-Mode Voltage
Rev. C | Page 10 of 24
5
09437-007
VOS (µV)
0.8
09437-004
VOS (µV)
–0.4
Figure 10. Input Offset Voltage Distribution
60
NUMBER OF AMPLIFIERS
–0.8
09437-005
NUMBER OF AMPLIFIERS
80
NUMBER OF AMPLIFIERS
VSY = 5V
VCM = VSY/2
90
Data Sheet
ADA4528-1/ADA4528-2
400
400
VSY = 2.5V
VCM = VSY/2
300
IB+
200
200
IB+
100
IB (pA)
100
IB (pA)
VSY = 5V
VCM = VSY/2
300
0
–100
0
I B–
–100
–200
–300
–300
–25
0
25
50
75
100
125
TEMPERATURE (°C)
–400
–50
09437-008
–400
–50
–25
0
25
50
75
100
125
TEMPERATURE (°C)
Figure 13. Input Bias Current vs. Temperature
09437-110
I B–
–200
Figure 16. Input Bias Current vs. Temperature
600
600
400
+85°C
400
+85°C
–40°C
200
–40°C
200
IB (pA)
IB (pA)
+25°C
+125°C
0
0
+25°C
–200
+125°C
–200
–400
–400
–600
0.5
1.0
1.5
2.0
2.5
VCM (V)
0
4
5
10
OUTPUT VOLTAGE (VOL) TO SUPPLY RAIL (V)
VSY = 2.5V
1
100m
–40°C
+25°C
+85°C
+125°C
1m
0.01
0.1
1
LOAD CURRENT (mA)
10
100
09437-014
OUTPUT VOLTAGE (VOL) TO SUPPLY RAIL (V)
3
Figure 17. Input Bias Current vs. Common-Mode Voltage
10
0.1m
0.001
2
VCM (V)
Figure 14. Input Bias Current vs. Common-Mode Voltage
10m
1
VS = 5V
1
100m
10m
–40°C
+25°C
+85°C
+125°C
1m
0.1m
0.001
0.01
0.1
1
LOAD CURRENT (mA)
10
100
Figure 18. Output Voltage (VOL) to Supply Rail vs. Load Current
Figure 15. Output Voltage (VOL) to Supply Rail vs. Load Current
Rev. C | Page 11 of 24
09437-017
0
–800
09437-009
–600
09437-012
VSY = 5V
VSY = 2.5V
ADA4528-1/ADA4528-2
Data Sheet
10
1
100m
–40°C
+25°C
+85°C
+125°C
1m
0.01
0.1
1
LOAD CURRENT (mA)
10
100m
100
Figure 19. Output Voltage (VOH) to Supply Rail vs. Load Current
OUTPUT VOLTAGE (VOL) TO SUPPLY RAIL (mV)
RL = 2kΩ
15
10
RL = 10kΩ
5
–25
0
25
50
75
TEMPERATURE (°C)
100
125
OUTPUT VOLTAGE (VOH) TO SUPPLY RAIL (mV)
25
RL = 2kΩ
20
15
10
RL = 10kΩ
5
0
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
0.1m
0.001
0.01
0.1
1
LOAD CURRENT (mA)
10
100
45
VSY = 5V
40
RL = 2kΩ
35
30
25
20
15
RL = 10kΩ
10
5
–25
0
25
50
75
TEMPERATURE (°C)
100
125
Figure 23. Output Voltage (VOL) to Supply Rail vs. Temperature
25
VSY = 5V
Figure 21. Output Voltage (VOH) to Supply Rail vs. Temperature
RL = 2kΩ
20
15
10
RL = 10kΩ
5
0
–50
09437-015
OUTPUT VOLTAGE (VOH) TO SUPPLY RAIL (mV)
Figure 20. Output Voltage (VOL) to Supply Rail vs. Temperature
VSY = 2.5V
1m
0
–50
09437-016
OUTPUT VOLTAGE (VOL) TO SUPPLY RAIL (mV)
VSY = 2.5V
0
–50
10m
Figure 22. Output Voltage (VOH) to Supply Rail vs. Load Current
25
20
–40°C
+25°C
+85°C
+125°C
09437-019
0.1m
0.001
1
–25
0
25
50
75
TEMPERATURE (°C)
100
125
Figure 24. Output Voltage (VOH) to Supply Rail vs. Temperature
Rev. C | Page 12 of 24
09437-117
10m
VSY = 5V
09437-013
OUTPUT VOLTAGE (VOH) TO SUPPLY RAIL (V)
VSY = 2.5V
09437-010
OUTPUT VOLTAGE (VOH) TO SUPPLY RAIL (V)
10
Data Sheet
ADA4528-1/ADA4528-2
2.0
2.00
+125°C
1.8
+85°C
1.50
ISY PER AMPLIFIER (mA)
ISY PER AMPLIFIER (mA)
1.75
+25°C
1.25
–40°C
1.00
0.75
0.50
VSY = 5.0V
1.6
VSY = 2.5V
1.4
1.2
2.0
2.5 3.0
VSY (V)
3.5
4.0
4.5
5.0
5.5
1.0
–50
–25
0
25
Figure 25. Supply Current vs. Supply Voltage
75
100
125
Figure 28. Supply Current vs. Temperature
135
120
90
90
90
90
60
45
60
45
120
135
PHASE
0
VSY = 2.5V
RL = 10kΩ
CL = 100pF
–30
1k
GAIN
30
10k
100k
–90
10M
1M
0
VSY = 5V
RL = 10kΩ
CL = 100pF
0
–45
09437-022
0
PHASE (Degrees)
GAIN
30
OPEN-LOOP GAIN (dB)
PHASE
FREQUENCY (Hz)
–30
1k
–45
10k
100k
Figure 29. Open-Loop Gain and Phase vs. Frequency
60
60
VSY = 2.5V
VSY = 5V
50
50
AV = 100
CLOSED-LOOP GAIN (dB)
AV = 100
40
30
AV = 10
20
10
AV = 1
0
40
30
AV = 10
20
10
AV = 1
0
–10
100
1k
10k
100k
1M
FREQUENCY (Hz)
10M
09437-026
–10
–20
10
–90
10M
1M
FREQUENCY (Hz)
Figure 26. Open-Loop Gain and Phase vs. Frequency
CLOSED-LOOP GAIN (dB)
OPEN-LOOP GAIN (dB)
50
TEMPERATURE (°C)
PHASE (Degrees)
1.5
1.0
09437-025
0.5
Figure 27. Closed-Loop Gain vs. Frequency
–20
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 30. Closed-Loop Gain vs. Frequency
Rev. C | Page 13 of 24
10M
09437-029
0
09437-021
0
09437-024
0.25
ADA4528-1/ADA4528-2
Data Sheet
140
160
VSY = 2.5V
140
VSY = 5V
VCM = VSY/2
120
120
CMRR (dB)
80
60
VCM = VSY/2
VCM = 1.1V
10k
100k
1M
10M
FREQUENCY (Hz)
0
100
09437-126
1k
1k
10k
100k
Figure 31. CMRR vs. Frequency
120
VSY = 5V
100
100
80
80
PSRR (dB)
60
PSRR+
40
60
PSRR+
40
PSRR–
PSRR–
20
20
0
0
10k
100k
1M
10M
FREQUENCY (Hz)
–20
100
09437-032
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 32. PSRR vs. Frequency
Figure 35. PSRR vs. Frequency
1k
1k
VSY = 2.5V
VSY = 5V
100
100
10
10
ZOUT (Ω)
AV = 100
AV = 10
1
AV = 1
AV = 100
AV = 1
0.1
0.01
0.01
1k
10k
100k
1M
FREQUENCY (Hz)
10M
Figure 33. Output Impedance vs. Frequency
AV = 10
1
0.1
09437-027
ZOUT (Ω)
1k
09437-035
PSRR (dB)
VSY = 2.5V
0.001
100
10M
Figure 34. CMRR vs. Frequency
120
–20
100
1M
FREQUENCY (Hz)
09437-031
20
0
100
60
40
40
20
80
0.001
100
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 36. Output Impedance vs. Frequency
Rev. C | Page 14 of 24
10M
09437-030
CMRR (dB)
100
100
ADA4528-1/ADA4528-2
VOLTAGE (1V/DIV)
TIME (20µs/DIV)
TIME (20µs/DIV)
Figure 40. Large Signal Transient Response
VOLTAGE (50mV/DIV)
VOLTAGE (50mV/DIV)
Figure 37. Large Signal Transient Response
VSY = ±2.5V
VIN = 100mV p-p
AV = 1
RL = 10kΩ
CL = 100pF
09437-038
VSY = ±1.25V
VIN = 100mV p-p
AV = 1
RL = 10kΩ
CL = 100pF
TIME (1µs/DIV)
TIME (1µs/DIV)
Figure 38. Small Signal Transient Response
Figure 41. Small Signal Transient Response
16
16
VSY = 2.5V
VIN = 100mV p-p
AV = 1
RL = 10kΩ
14
VSY = 5V
VIN = 100mV p-p
AV = 1
RL = 10kΩ
14
12
OS+
10
8
OS–
6
10
8
6
4
4
2
2
1
10
100
1000
LOAD CAPACITANCE (pF)
OS–
0
09437-033
0
OS+
1
10
100
1000
LOAD CAPACITANCE (pF)
Figure 39. Small Signal Overshoot vs. Load Capacitance
Figure 42. Small Signal Overshoot vs. Load Capacitance
Rev. C | Page 15 of 24
09437-036
OVERSHOOT (%)
12
OVERSHOOT (%)
09437-037
VSY = ±2.5V
VIN = 4V p-p
AV = 1
RL = 10kΩ
CL = 100pF
09437-034
VSY = ±1.25V
VIN = 2V p-p
AV = 1
RL = 10kΩ
CL = 100pF
09437-041
VOLTAGE (0.5V/DIV)
Data Sheet
INPUT VOLTAGE (V)
Data Sheet
VSY = ±1.25V
AV = –10
VIN = 187.5mV
RL = 10kΩ
CL = 100pF
OUTPUT
1
0
–1
TIME (10µs/DIV)
–0.5
3
1
OUTPUT
0
–1
TIME (10µs/DIV)
INPUT VOLTAGE (V)
Figure 46. Positive Overload Recovery
VSY = ±1.25V
AV = –10
VIN = 187.5mV
RL = 10kΩ
CL = 100pF
INPUT
0
–0.5
1
OUTPUT
0
–1
–2
TIME (10µs/DIV)
–1
VSY = ±2.5V
AV = –10
VIN = 375mV
RL = 10kΩ
CL = 100pF
09437-039
0
OUTPUT VOLTAGE (V)
1
OUTPUT
–2
OUTPUT VOLTAGE (V)
INPUT
0
0.5
09437-042
0.5
–3
TIME (10µs/DIV)
Figure 47. Negative Overload Recovery
Figure 44. Negative Overload Recovery
INPUT
INPUT
VOLTAGE (2V/DIV)
VSY = 2.5V
RL = 10kΩ
CL = 100pF
DUT AV = –1
+7.5mV
ERROR BAND
POST GAIN = 5
0
–7.5mV
+20mV
OUTPUT
0
ERROR BAND
POST GAIN = 5
–20mV
09437-047
OUTPUT
VSY = 5V
RL = 10kΩ
CL = 100pF
DUT AV = –1
09437-044
VOLTAGE (1V/DIV)
INPUT VOLTAGE (V)
VSY = ±2.5V
AV = –10
VIN = 375mV
RL = 10kΩ
CL = 100pF
2
Figure 43. Positive Overload Recovery
–0.5
INPUT
2
OUTPUT VOLTAGE (V)
–0.5
0
OUTPUT VOLTAGE (V)
INPUT
0
0.5
09437-043
0.5
09437-040
INPUT VOLTAGE (V)
ADA4528-1/ADA4528-2
TIME (10µs/DIV)
TIME (10µs/DIV)
Figure 45. Positive Settling Time to 0.1%
Figure 48. Positive Settling Time to 0.1%
Rev. C | Page 16 of 24
Data Sheet
ADA4528-1/ADA4528-2
VSY = 2.5V
RL = 10kΩ
CL = 100pF
DUT AV = –1
+7.5mV
OUTPUT
0
ERROR BAND
POST GAIN = 5
INPUT
VOLTAGE (2V/DIV)
VOLTAGE (1V/DIV)
INPUT
VSY = 5V
RL = 10kΩ
CL = 100pF
DUT AV = –1
+20mV
ERROR BAND
POST GAIN = 5
OUTPUT
0
–7.5mV
TIME (10µs/DIV)
TIME (10µs/DIV)
Figure 49. Negative Settling Time to 0.1%
Figure 52. Negative Settling Time to 0.1%
100
10
10
1
100
1k
10k
FREQUENCY (Hz)
VSY = 5V
AV = 100
VCM = VSY/2
10
1
1
1k
10k
Figure 53. Voltage Noise Density vs. Frequency
10
10
1
1
10
100
1k
10k
FREQUENCY (Hz)
100k
Figure 51. Current Noise Density vs. Frequency
VSY = 5V
AV = 100
VCM = VSY/2
1
0.1
1
10
100
1k
10k
FREQUENCY (Hz)
Figure 54. Current Noise Density vs. Frequency
Rev. C | Page 17 of 24
100k
09437-153
CURRENT NOISE DENSITY (pA/√Hz)
VSY = 2.5V
AV = 100
VCM = VSY/2
09437-150
CURRENT NOISE DENSITY (pA/√Hz)
100
FREQUENCY (Hz)
Figure 50. Voltage Noise Density vs. Frequency
0.1
10
09437-049
VOLTAGE NOISE DENSITY (nV/√Hz)
VSY = 2.5V
AV = 100
VCM = VSY/2
09437-046
VOLTAGE NOISE DENSITY (nV/√Hz)
100
1
09437-048
09437-045
–20mV
ADA4528-1/ADA4528-2
Data Sheet
VSY = 5V
AV = 100
VCM = VSY/2
TIME (1s/DIV)
TIME (1s/DIV)
Figure 58. 0.1 Hz to 10 Hz Noise
10
1
1
0.1
0.001
0.001
0.1
VSY = 5V
AV = 1
f = 1kHz
RL = 10kΩ
0.01
VSY = 2.5V
AV = 1
f = 1kHz
RL = 10kΩ
0.01
0.1
1
10
AMPLITUDE (V p-p)
0.001
0.001
0.01
0.1
1
10
AMPLITUDE (V p-p)
Figure 56. THD + N vs. Amplitude
09437-155
THD + N (%)
10
09437-152
Figure 59. THD + N vs. Amplitude
1
1
VSY = 2.5V
AV = 1
RL = 10kΩ
80kHz LOW-PASS FILTER
VIN = 2V p-p
VSY = 5V
AV = 1
RL = 10kΩ
80kHz LOW-PASS FILTER
VIN = 2V p-p
THD + N (%)
0.1
THD + N (%)
0.1
0.001
10
0.01
100
1k
10k
FREQUENCY (Hz)
100k
09437-056
0.01
Figure 57. THD + N vs. Frequency
0.001
10
100
1k
10k
FREQUENCY (Hz)
Figure 60. THD + N vs. Frequency
Rev. C | Page 18 of 24
100k
09437-057
THD + N (%)
Figure 55. 0.1 Hz to 10 Hz Noise
0.01
09437-053
09437-050
INPUT VOLTAGE (20nV/DIV)
INPUT VOLTAGE (20nV/DIV)
VSY = 2.5V
AV = 100
VCM = VSY/2
Data Sheet
ADA4528-1/ADA4528-2
APPLICATIONS INFORMATION
The ADA4528-1/ADA4528-2 feature rail-to-rail input and output
with a supply voltage from 2.2 V to 5.5 V. Figure 61 shows the
input and output waveforms of the ADA4528-1/ADA4528-2
configured as a unity-gain buffer with a supply voltage of ±2.5 V
and a resistive load of 10 kΩ. With an input voltage of ±2.5 V, the
ADA4528-1/ADA4528-2 allow the output to swing very close to
both rails. Additionally, the parts do not exhibit phase reversal.
3
1
For more information about the chopper architecture of the
ADA4528-1/ADA4528-2, see the AN-1114 Application Note,
Lowest Noise Zero-Drift Amplifier Has 5.6 nV/√Hz Voltage
Noise Density.
0
–1
INPUT PROTECTION
–2
The ADA4528-1/ADA4528-2 have internal ESD protection diodes
that are connected between the inputs and each supply rail. These
diodes protect the input transistors in the event of electrostatic
discharge and are reverse biased during normal operation. This
protection scheme allows voltages as high as approximately 300 mV
beyond the rails to be applied at the input of either terminal
without causing permanent damage (see Table 4 in the Absolute
Maximum Ratings section).
When either input exceeds one of the supply rails by more than
300 mV, the ESD diodes become forward biased and large amounts
of current begin to flow through them. Without current limiting,
this excessive fault current causes permanent damage to the device.
If the inputs will be subjected to overvoltage conditions, insert a
resistor in series with each input to limit the input current to 10 mA
maximum. However, consider the resistor thermal noise effect
on the entire circuit.
For example, at a 5 V supply voltage, the broadband voltage noise
of the ADA4528-1/ADA4528-2 is approximately 6 nV/√Hz (at
unity gain). A 1 kΩ resistor has thermal noise of 4 nV/√Hz. Adding
a 1 kΩ resistor at the noninverting input pin increases the total
noise by 30% root sum square (rss).
VIN
VOUT
2
VSY = ±2.5V
AV = 1
RL = 10kΩ
–3
TIME (200µs/DIV)
09437-059
Offset voltage errors due to common-mode voltage swings
and power supply variations are also corrected by the chopping
technique, resulting in a typical CMRR figure of 158 dB and a
PSRR figure of 150 dB at 2.5 V supply voltage. The ADA4528-1/
ADA4528-2 have low broadband noise of 5.6 nV/√Hz (at f = 1 kHz,
AV = +100, and VSY = 2.5 V) with no 1/f noise component. These
features are ideal for amplification of low level signals in dc or
subhertz high precision applications.
RAIL-TO-RAIL INPUT AND OUTPUT
VOLTAGE (V)
The ADA4528-1/ADA4528-2 are precision, ultralow noise,
zero-drift operational amplifiers that feature a patented chopping technique. This chopping technique offers ultralow input
offset voltage of 0.3 µV typical and input offset voltage drift of
0.002 µV/°C typical.
Figure 61. Rail-to-Rail Input and Output
NOISE CONSIDERATIONS
For more information about the noise characteristics of the
ADA4528-1/ADA4528-2, see the AN-1114 Application Note,
Lowest Noise Zero-Drift Amplifier Has 5.6 nV/√Hz Voltage Noise
Density.
1/f Noise
1/f noise, also known as pink noise or flicker noise, is inherent
in semiconductor devices and increases as frequency decreases.
At low frequency, 1/f noise is a major noise contributor and
causes a significant output voltage offset when amplified by the
noise gain of the circuit. However, the ADA4528-1/ADA4528-2
eliminate the 1/f noise internally, thus making these parts an
excellent choice for dc or subhertz high precision applications.
The 0.1 Hz to 10 Hz amplifier voltage noise is only 97 nV p-p
(AV = +100) at a supply voltage of 2.5 V.
The low frequency 1/f noise, which appears as a slow varying
offset to the ADA4528-1/ADA4528-2, is greatly reduced by
the chopping technique. This reduction in 1/f noise allows the
ADA4528-1/ADA4528-2 to have much lower noise at dc and
low frequency compared to standard low noise amplifiers that
are susceptible to 1/f noise. Figure 50 and Figure 53 show the
voltage noise density of the amplifier with no 1/f noise.
Rev. C | Page 19 of 24
ADA4528-1/ADA4528-2
Data Sheet
Source Resistance
Voltage Noise Density with Different Gain Configurations
With 5.6 nV/√Hz of broadband noise at 1 kHz (VSY = 2.5 V
and AV = +100), the ADA4528-1/ADA4528-2 are among the
lowest noise zero-drift amplifiers currently available in the
industry. Therefore, it is important to carefully select the input
source resistance to maintain a total low noise.
Figure 62 shows the voltage noise density vs. closed-loop gain of a
zero-drift amplifier from a leading competitor. The voltage noise
density of the amplifier increases from 11 nV/√Hz to 21 nV/√Hz
as the closed-loop gain decreases from 1000 to 1.
24
These uncorrelated noise sources can be summed up in a root
sum squared (rss) manner using the following equation:
en total = [en2 + 4 kTRS + (in × RS)2]1/2
where:
en is the input voltage noise of the amplifier (V/√Hz).
k is the Boltzmann’s constant (1.38 × 10−23 J/K).
T is the temperature in Kelvin (K).
RS is the total input source resistance (Ω).
in is the input current noise of the amplifier (A/√Hz).
VSY = 5V
f = 100Hz
COMPETITOR A
20
16
12
8
4
09437-061
VOLTAGE NOISE DENSITY (nV/√Hz)
The total input referred broadband noise (en total) from any
amplifier is primarily a function of three types of noise: input
voltage noise, input current noise, and thermal (Johnson) noise
from the external resistors.
0
1
10
100
1000
CLOSED-LOOP GAIN (V/V)
Figure 62. Competitor A: Voltage Noise Density vs. Closed-Loop Gain
Figure 63 shows the voltage noise density vs. frequency of the
ADA4528-1/ADA4528-2 for three different gain configurations.
The ADA4528-1/ADA4528-2 offer a constant input voltage
noise density of 6 nV/√Hz to 7 nV/√Hz, regardless of the gain
configuration.
where BW is the bandwidth in hertz.
This analysis is valid for broadband noise calculation. If the
bandwidth of concern includes the chopping frequency, more
complicated calculations must be made to include the effect of
the noise energy spectrum at the chopping frequency (see the
Residual Voltage Ripple section).
With a low source resistance of RS < 1 kΩ, the voltage noise
of the amplifier dominates. As source resistance increases, the
thermal noise of RS dominates. As the source resistance increases
further, where RS > 100 kΩ, the current noise becomes the main
contributor to the total input noise. A good selection table for low
noise op amps can be found in the AN-940 Application Note, Low
Noise Amplifier Selection Guide for Optimal Noise Performance.
100
VSY = 5V
VCM = VSY/2
10
AV = 1
AV = 10
AV = 100
1
1
10
100
1k
10k
FREQUENCY (Hz)
Figure 63. Voltage Noise Density vs. Frequency with Different Gain
Configurations
Rev. C | Page 20 of 24
09437-062
en,rms = en total × √BW
VOLTAGE NOISE DENSITY (nV/√Hz)
The total equivalent rms noise over a specific bandwidth is
expressed as
Data Sheet
ADA4528-1/ADA4528-2
Residual Voltage Ripple
1.8
Although autocorrection feedback (ACFB) suppresses the chopping related voltage ripple, higher noise spectrum exists at the
chopping frequency and its harmonics due to the remaining ripple.
Figure 64 shows the voltage noise density of the ADA4528-1/
ADA4528-2 configured in unity gain. A noise energy spectrum
of 50 nV/√Hz can be seen at the chopping frequency of 200 kHz.
This noise energy spectrum is significant when the op amp has a
closed-loop frequency that is higher than the chopping frequency.
1.6
ISY PER AMPLIFIER (mA)
1.4
1.0
0.8
0.6
0.4
VSY = 5V
AV = 1
VCM = VSY/2
ISY–
ISY+
0.2
0
0
1
2
3
4
5
VSY (V)
09437-066
100
Figure 66. Supply Current vs. Supply Voltage (Voltage Follower)
10
Figure 67 and Figure 68 show the ADA4528-1 configured as
comparators, with 1kΩ resistors in series with the input pins.
Figure 69 shows the supply currents for both configurations.
Supply currents do not change significantly, where ISY+ = ISY− =
1.5 mA per amplifier at 5 V of supplies.
+VSY
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
10M
Figure 64. Voltage Noise Density vs. Frequency
To further suppress the noise at the chopping frequency, it is
recommended that a post filter be placed at the output of the
amplifier. For more information about residual voltage ripple,
see the AN-1114 Application Note, Lowest Noise Zero-Drift
Amplifier Has 5.6 nV/√Hz Voltage Noise Density.
ISY+
A1
1kΩ
ADA4528-1
VOUT
1/2
1kΩ
COMPARATOR OPERATION
Figure 65 shows the ADA4528-1 configured as a voltage
follower with an input voltage that is always kept at midpoint
of the power supplies. A1 and A2 indicate the placement of
ammeters to measure supply current. As shown in Figure 66,
in normal operating condition, ISY+ = ISY− = 1.5 mA per
amplifier with 5 V of supplies.
ISY–
A2
–VSY
Figure 67. Comparator A
+VSY
+VSY
A1
A1
ISY+
ISY+
1kΩ
ADA4528-1
VOUT
1/2
ADA4528-1
VOUT
1/2
1kΩ
A2
1kΩ
ISY–
–VSY
A2
ISY–
–VSY
Figure 68. Comparator B
09437-065
1kΩ
Figure 65. Voltage Follower
Rev. C | Page 21 of 24
09437-068
1
09437-067
1
09437-063
VOLTAGE NOISE DENSITY (nV/√Hz)
1.2
ADA4528-1/ADA4528-2
Data Sheet
junction. The most common metallic junctions on a circuit
board are solder-to-board trace and solder-to-component lead.
1.8
1.6
Figure 70 shows a cross section of a surface-mount component
soldered to a PCB. A variation in temperature across the board
(where TA1 ≠ TA2) causes a mismatch in the Seebeck voltages at
the solder joints, thereby resulting in thermal voltage errors
that degrade the ultralow offset voltage performance of the
ADA4528-1/ADA4528-2.
1.2
1.0
0.8
0.6
COMPONENT
LEAD
0.4
ISY–
ISY+
VSC1 +
0
0
1
2
3
4
5
VSY (V)
09437-069
0.2
SURFACE-MOUNT
COMPONENT
VSC2
SOLDER
+ VTS2
PC BOARD
Figure 69. Supply Current vs. Supply Voltage (Comparator A and
Comparator B)
TA1
COPPER
TRACE
For more details on op amps as comparators, refer to the
AN-849 Application Note, Using Op Amps as Comparators.
+
VTS1 +
TA2
IF TA1 ≠ TA2, THEN
VTS1 + VSC1 ≠ VTS2 + VSC2
09437-154
ISY PER AMPLIFIER (mA)
1.4
Figure 70. Mismatch in Seebeck Voltages Causes
Seebeck Voltage Error
PRINTED CIRCUIT BOARD LAYOUT
The ADA4528-1/ADA4528-2 are high precision devices with
ultralow offset voltage and noise. Therefore, care must be taken
in the design of the printed circuit board (PCB) layout to achieve
the optimum performance of the ADA4528-1/ADA4528-2 at
board level.
To avoid leakage currents, keep the surface of the board clean
and free of moisture. Coating the board surface creates a barrier
to moisture accumulation and reduces parasitic resistance on
the board.
To minimize power supply disturbances caused by output current
variation, properly bypass the power supplies and keep the supply
traces short. Connect bypass capacitors as close as possible to the
device supply pins.
Stray capacitances are a concern at the outputs and the inputs of
the amplifier. It is recommended that signal traces be kept at a
distance of at least 5 mm from supply lines to minimize coupling.
To minimize these thermocouple effects, orient resistors so that
heat sources warm both ends equally. Where possible, the input
signal paths should contain matching numbers and types of components to match the number and type of thermocouple junctions.
For example, dummy components, such as zero value resistors, can
be used to match the thermoelectric error source (real resistors
in the opposite input path). Place matching components in close
proximity and orient them in the same manner to ensure equal
Seebeck voltages, thus canceling thermal errors. Additionally, use
leads of equal length to keep thermal conduction in equilibrium.
Keep heat sources on the PCB as far away from the amplifier
input circuitry as practical.
It is highly recommended that a ground plane be used. A ground
plane helps to distribute heat throughout the board, maintains a
constant temperature across the board, and reduces EMI noise
pickup.
A potential source of offset error is the Seebeck voltage on the
circuit board. The Seebeck voltage occurs at the junction of two
dissimilar metals and is a function of the temperature of the
Rev. C | Page 22 of 24
Data Sheet
ADA4528-1/ADA4528-2
OUTLINE DIMENSIONS
3.20
3.00
2.80
8
3.20
3.00
2.80
1
5.15
4.90
4.65
5
4
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.40
0.25
0.80
0.55
0.40
0.23
0.09
6°
0°
10-07-2009-B
0.15
0.05
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 71. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
3.10
3.00 SQ
2.90
0.50 BSC
8
5
1.70
1.60 SQ
1.50
EXPOSED
PAD
0.50
0.40
0.30
0.80
0.75
0.70
SEATING
PLANE
0.30
0.25
0.20
1
4
BOTTOM VIEW
TOP VIEW
0.05 MAX
0.02 NOM
COPLANARITY
0.08
0.203 REF
PIN 1
INDICATOR
(R 0.15)
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
COMPLIANT TO JEDEC STANDARDS MO-229-WEED
07-06-2011-A
PIN 1 INDEX
AREA
Figure 72. 8-Lead Lead Frame Chip Scale Package [LFCSP_WD]
3 mm × 3 mm Body, Very Very Thin, Dual Lead
(CP-8-12)
Dimensions shown in millimeters
ORDERING GUIDE
Model 1
ADA4528-1ARMZ
ADA4528-1ARMZ-R7
ADA4528-1ARMZ-RL
ADA4528-1ACPZ-R7
ADA4528-1ACPZ-RL
ADA4528-2ARMZ
ADA4528-2ARMZ-R7
ADA4528-2ARMZ-RL
1
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
Package Description
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
8-Lead Lead Frame Chip Scale Package [LFCSP_WD]
8-Lead Lead Frame Chip Scale Package [LFCSP_WD]
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
Z = RoHS Compliant Part.
Rev. C | Page 23 of 24
Package Option
RM-8
RM-8
RM-8
CP-8-12
CP-8-12
RM-8
RM-8
RM-8
Branding
A2R
A2R
A2R
A2R
A2R
A32
A32
A32
ADA4528-1/ADA4528-2
Data Sheet
NOTES
©2011–2012 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09437-0-9/12(C)
Rev. C | Page 24 of 24