AD ADA4665-2ARZ-R7 16 v, 1 mhz, cmos rail-to-rail input/output operational amplifier Datasheet

16 V, 1 MHz, CMOS Rail-to-Rail
Input/Output Operational Amplifier
ADA4665-2
PIN CONFIGURATIONS
Lower power at high voltage: 290 μA per amplifier typical
Low input bias current: 1 pA maximum
Wide bandwidth: 1.2 MHz typical
Slew rate: 1 V/μs typical
Offset voltage drift: 3 μV/°C typical
Single-supply operation: 5 V to 16 V
Dual-supply operation: ±2.5 V to ±8 V
Unity gain stable
OUT A 1
–IN A 2
+IN A 3
ADA4665-2
TOP VIEW
(Not to Scale)
V– 4
8
V+
7
OUT B
6
–IN B
5
+IN B
07650-001
FEATURES
Figure 1. 8-Lead SOIC
APPLICATIONS
8
V+
–IN A 2
ADA4665-2
7
OUT B
+IN A 3
TOP VIEW
(Not to Scale)
6
–IN B
5
+IN B
V– 4
Portable systems
High density power budget systems
Medical equipment
Physiological measurement
Precision references
Multipole filters
Sensors
Transimpedance amplifiers
Buffer/level shifting
07650-002
OUT A 1
Figure 2. 8-Lead MSOP
GENERAL DESCRIPTION
The ADA4665-2 is a rail-to-rail input/output dual amplifier
optimized for lower power budget designs. The ADA4665-2
offers a low supply current of 400 μA maximum per amplifier
at 25°C and 600 μA maximum per amplifier over the extended
industrial temperature range. This feature makes the ADA4665-2
well suited for low power applications. In addition, the ADA4665-2
has a very low bias current of 1 pA maximum, low offset voltage
drift of 3 μV/°C, and bandwidth of 1.2 MHz. The combination of
these features, together with a wide supply voltage range from
5 V to 16 V, allows the device to be used in a wide variety of
other applications, including process control, instrumentation
equipment, buffering, and sensor front ends. Furthermore, its
rail-to-rail input and output swing adds to its versatility. The
ADA4665-2 is specified from −40°C to +125°C and is available
in standard SOIC and MSOP packages.
Table 1. Low Cost Rail-to-Rail Input/Output Op Amps
Supply
Single
Dual
Quad
5V
AD8541
AD8542
AD8544
16 V
ADA4665-2
Table 2. Other Rail-to-Rail Input/Output Op Amps
Supply
Single
Dual
Quad
5V
AD8603
AD8607
AD8609
16 V
AD8663
AD8667
AD8669
36 V
ADA4091-2
Rev. 0
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.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2009 Analog Devices, Inc. All rights reserved.
ADA4665-2
TABLE OF CONTENTS
Features .............................................................................................. 1
Thermal Resistance .......................................................................5
Applications ....................................................................................... 1
ESD Caution...................................................................................5
Pin Configurations ........................................................................... 1
Typical Performance Characteristics ..............................................6
General Description ......................................................................... 1
Applications Information .............................................................. 15
Revision History ............................................................................... 2
Rail-to-Rail Input Operation .................................................... 15
Specifications..................................................................................... 3
Current Shunt Sensor ................................................................ 15
Electrical Characteristics—16 V Operation ............................. 3
Active Filters ............................................................................... 15
Electrical Characteristics—5 V Operation................................ 4
Outline Dimensions ....................................................................... 17
Absolute Maximum Ratings............................................................ 5
Ordering Guide .......................................................................... 17
REVISION HISTORY
1/09—Revision 0: Initial Version
Rev. 0 | Page 2 of 20
ADA4665-2
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS—16 V OPERATION
VSY = 16 V, VCM = VSY/2, TA = 25°C, unless otherwise noted.
Table 3.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Test Conditions/Comments
VOS
Offset Voltage Drift
Input Bias Current
∆VOS/∆T
IB
VCM = 16 V
VCM = 0 V to 16 V
−40°C ≤ TA ≤ +125°C
−40°C ≤ TA ≤ +125°C
Min
Typ
Max
Unit
1
1
4
6
9
mV
mV
mV
μV/°C
pA
pA
pA
pA
V
dB
dB
dB
dB
GΩ
pF
pF
3
0.1
−40°C ≤ TA ≤ +125°C
Input Offset Current
IOS
Input Voltage Range
Common-Mode Rejection Ratio
CMRR
Large Signal Voltage Gain
AVO
Input Resistance
Input Capacitance, Differential Mode
Input Capacitance, 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%
Gain Bandwidth Product
Phase Margin
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
0.1
−40°C ≤ TA ≤ +125°C
−40°C ≤ TA ≤ +125°C
VCM = 0 V to 16 V
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ, VO = 0.5 V to 15 V
−40°C ≤ TA ≤ +125°C
0
55
50
85
75
RIN
CINDM
CINCM
VOH
VOL
ISC
ZOUT
PSRR
ISY
1
200
1
40
16
75
100
4
2
7
RL = 100 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 100 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
15.95
15.9
15.9
15.8
15.95
4
40
7.5
15
75
150
±30
100
f = 100 kHz, AV = 1
VSY = 5 V to 16 V
−40°C ≤ TA ≤ +125°C
IO = 0 mA
−40°C ≤ TA ≤ +125°C
15.99
70
65
95
290
400
600
V
V
V
V
mV
mV
mV
mV
mA
Ω
dB
dB
μA
μA
SR
tS
GBP
ΦM
RL = 10 kΩ, CL = 50 pF, AV = 1
VIN = 1 V step, RL = 2 kΩ, CL = 50 pF
RL = 10 kΩ, CL = 50 pF, AV = 1
RL = 10 kΩ, CL = 50 pF, AV = 1
1
6.5
1.2
50
V/μs
μs
MHz
Degrees
en p-p
en
f = 0.1 Hz to 10 Hz
f = 1 kHz
f = 10 kHz
f = 1 kHz
3
32
27
50
μV p-p
nV/√Hz
nV/√Hz
fA/√Hz
in
Rev. 0 | Page 3 of 20
ADA4665-2
ELECTRICAL CHARACTERISTICS—5 V OPERATION
VSY = 5 V, VCM = VSY/2, TA = 25°C, unless otherwise noted.
Table 4.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Test Conditions/Comments
VOS
Offset Voltage Drift
Input Bias Current
∆VOS/∆T
IB
VCM = 5 V
VCM = 0 V to 5 V
−40°C ≤ TA ≤ +125°C
−40°C ≤ TA ≤ +125°C
Min
Typ
Max
Unit
1
1
4
6
9
mV
mV
mV
μV/°C
pA
pA
pA
pA
V
dB
dB
dB
dB
GΩ
pF
pF
3
0.1
−40°C ≤ TA ≤ +125°C
Input Offset Current
IOS
Input Voltage Range
Common-Mode Rejection Ratio
CMRR
Large Signal Voltage Gain
AVO
Input Resistance
Input Capacitance, Differential Mode
Input Capacitance, 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%
Gain Bandwidth Product
Phase Margin
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
0.1
−40°C ≤ TA ≤ +125°C
−40°C ≤ TA ≤ +125°C
VCM = 0 V to 5 V
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ, VO = 0.5 V to 4.5 V
−40°C ≤ TA ≤ +125°C
0
55
50
85
75
RIN
CINDM
CINCM
VOH
VOL
ISC
ZOUT
PSRR
ISY
1
100
1
10
5
75
100
1
2
7
RL = 100 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 100 kΩ to VCM
−40°C ≤ TA ≤ +125°C
RL = 10 kΩ to VCM
−40°C ≤ TA ≤ +125°C
4.95
4.9
4.9
4.8
4.96
3
30
5
10
50
100
±8
100
f = 100 kHz, AV = 1
VSY = 5 V to 16 V
−40°C ≤ TA ≤ +125°C
IO = 0 mA
−40°C ≤ TA ≤ +125°C
4.99
70
65
95
270
350
600
V
V
V
V
mV
mV
mV
mV
mA
Ω
dB
dB
μA
μA
SR
tS
GBP
ΦM
RL = 10 kΩ, CL = 50 pF, AV = 1
VIN = 1 V step, RL = 2 kΩ, CL = 50 pF
RL = 10 kΩ, CL = 50 pF, AV = 1
RL = 10 kΩ, CL = 50 pF, AV = 1
1
6.5
1.2
50
V/μs
μs
MHz
Degrees
en p-p
en
f = 0.1 Hz to 10 Hz
f = 1 kHz
f = 10 kHz
f = 1 kHz
3
32
27
50
μV p-p
nV/√Hz
nV/√Hz
fA/√Hz
in
Rev. 0 | Page 4 of 20
ADA4665-2
ABSOLUTE MAXIMUM RATINGS
THERMAL RESISTANCE
Table 5.
Parameter
Supply Voltage
Input Voltage1
Input Current
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
16.5 V
GND − 0.3 V to 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. This
value was measured using a 4-layer JEDEC standard printed
circuit board.
Table 6. Thermal Resistance
Package Type
8-Lead SOIC_N (R-8)
8-Lead MSOP (RM-8)
ESD CAUTION
The input pins have clamp diodes to the power supply pins.
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. 0 | Page 5 of 20
θJA
158
186
θJC
43
52
Unit
°C/W
°C/W
ADA4665-2
TYPICAL PERFORMANCE CHARACTERISTICS
TA = 25°C, unless otherwise noted.
70
70
VSY = 5V
VCM = VSY/2
VSY = 16V
VCM = VSY/2
60
NUMBER OF AMPLIFIERS
50
40
30
20
40
30
20
10
–5
–4
–3
–2
–1
0
1
VOS (mV)
2
3
4
5
6
0
–6
07650-006
0
–6
–5
Figure 3. Input Offset Voltage Distribution
–1
0
1
VOS (mV)
2
3
4
5
6
VSY = 16V
–40°C ≤ TA ≤ +125°C
9
8
7
6
5
4
3
7
6
5
4
3
2
2
1
1
0
1
2
3
4
5
6
TCVOS (µV/°C)
7
8
9
10
0
0
Figure 4. Input Offset Voltage Drift Distribution
2
3
4
5
6
TCVOS (µV/°C)
7
8
9
10
Figure 7. Input Offset Voltage Drift Distribution
5
5
VSY = 5V
4
2
2
VOS (mV)
3
1
0
1
0
–1
–1
–2
–2
–3
–3
1
2
3
4
VCM (V)
5
–4
07650-008
0
VSY = 16V
4
3
–4
1
07650-004
NUMBER OF AMPLIFIERS
8
07650-007
NUMBER OF AMPLIFIERS
–2
10
VSY = 5V
–40°C ≤ TA ≤ +125°C
9
VOS (mV)
–3
Figure 6. Input Offset Voltage Distribution
10
0
–4
07650-003
10
50
Figure 5. Input Offset Voltage vs. Common-Mode Voltage
0
2
4
6
8
VCM (V)
10
12
14
Figure 8. Input Offset Voltage vs. Common-Mode Voltage
Rev. 0 | Page 6 of 20
16
07650-005
NUMBER OF AMPLIFIERS
60
ADA4665-2
TA = 25°C, unless otherwise noted.
1k
100
1k
VSY = 5V
IB+
IB–
100
1
1
0.1
0.1
0.01
0.01
50
75
TEMPERATURE (°C)
100
125
0.001
25
50
Figure 9. Input Bias Current vs. Temperature
1k
75
TEMPERATURE (°C)
1k
100
VSY = 16V
100
125°C
10
105°C
125°C
IB (pA)
85°C
0.1
1
85°C
0.1
25°C
0.01
0.01
0.001
0.001
1
2
3
4
5
VCM (V)
0.0001
07650-013
0
0
2
4
6
8
VCM (V)
10
12
14
16
Figure 13. Input Bias Current vs. Input Common-Mode Voltage
10k
OUTPUT VOLTAGE (VOH) TO SUPPLY RAIL (mV)
10k
VSY = 5V
1k
100
10
–40°C
+25°C
+85°C
+125°C
1
0.1
0.001
0.01
0.1
1
LOAD CURRENT (mA)
10
100
07650-014
OUTPUT VOLTAGE (VOH) TO SUPPLY RAIL (mV)
Figure 10. Input Bias Current vs. Input Common-Mode Voltage
25°C
Figure 11. Output Voltage (VOH) to Supply Rail vs. Load Current
VSY = 16V
1k
100
10
1
–40°C
+25°C
+85°C
+125°C
0.1
0.01
0.001
0.01
0.1
1
LOAD CURRENT (mA)
10
100
Figure 14. Output Voltage (VOH) to Supply Rail vs. Load Current
Rev. 0 | Page 7 of 20
07650-011
IB (pA)
105°C
1
0.0001
125
Figure 12. Input Bias Current vs. Temperature
VSY = 5V
10
100
07650-010
0.001
25
07650-009
IB (pA)
10
07650-012
IB (pA)
10
VSY = 16V
IB+
IB–
ADA4665-2
1k
100
10
–40°C
+25°C
+85°C
+125°C
1
0.1
0.001
0.01
0.1
1
LOAD CURRENT (mA)
10
10k
100
1k
100
10
0.1
0.001
0.1
1
LOAD CURRENT (mA)
15.99
RL = 100kΩ
100
RL = 100kΩ
15.98
4.97
4.96
4.95
RL = 10kΩ
4.94
VSY = 5V
4.93
15.97
15.96
15.95
15.94
15.93
15.91
0
25
50
TEMPERATURE (°C)
75
100
125
15.90
–50
07650-019
–25
RL = 10kΩ
15.92
Figure 16. Output Voltage (VOH) vs. Temperature
VSY = 16V
–25
0
25
50
TEMPERATURE (°C)
75
100
125
07650-016
OUTPUT VOLTAGE, VOH (V)
4.98
Figure 19. Output Voltage (VOH) vs. Temperature
60
60
VSY = 5V
VSY = 16V
50
RL = 10kΩ
30
20
10
RL = 10kΩ
40
30
20
10
RL = 100kΩ
RL = 100kΩ
0
25
50
TEMPERATURE (°C)
75
100
125
0
–50
07650-020
–25
Figure 17. Output Voltage (VOL) vs. Temperature
–25
0
25
50
TEMPERATURE (°C)
75
100
Figure 20. Output Voltage (VOL) vs. Temperature
Rev. 0 | Page 8 of 20
125
07650-017
OUTPUT VOLTAGE, VOL (mV)
50
40
0
–50
10
16.00
4.99
OUTPUT VOLTAGE, VOH (V)
0.01
Figure 18. Output Voltage (VOL) to Supply Rail vs. Load Current
5.00
OUTPUT VOLTAGE, VOL (mV)
–40°C
+25°C
+85°C
+125°C
1
Figure 15. Output Voltage (VOL) to Supply Rail vs. Load Current
4.92
–50
VSY = 16V
07650-015
VSY = 5V
OUTPUT VOLTAGE (VOL) TO SUPPLY RAIL (mV)
10k
07650-018
OUTPUT VOLTAGE (VOL) TO SUPPLY RAIL (mV)
TA = 25°C, unless otherwise noted.
ADA4665-2
TA = 25°C, unless otherwise noted.
135
45
20
GAIN
0
0
OPEN-LOOP GAIN (dB)
90
PHASE (Degrees)
PHASE
–40
1k
10k
100k
FREQUENCY (Hz)
–90
10M
1M
PHASE
40
20
45
GAIN
0
–40
1k
40
30
CLOSED-LOOP GAIN (dB)
AV = 10
20
10
0
AV = 1
–10
–20
0
100M
AV = 1
–20
–40
10M
AV = 10
–10
–40
10k
100k
1M
FREQUENCY (Hz)
–50
100
Figure 22. Closed-Loop Gain vs. Frequency
1k
VSY = 5V
100
10k
100k
1M
FREQUENCY (Hz)
10M
100M
VSY = 16V
100
AV = 100
ZOUT (Ω)
10
AV = 10
10
1
AV = 100
AV = 10
AV = 1
0.01
10
AV = 1
0.1
100
1k
10k
100k
FREQUENCY (Hz)
1M
10M
0.01
10
Figure 23. Output Impedance vs. Frequency
100
1k
10k
100k
FREQUENCY (Hz)
1M
Figure 26. Output Impedance vs. Frequency
Rev. 0 | Page 9 of 20
10M
07650-023
0.1
07650-026
ZOUT (Ω)
1k
Figure 25. Closed-Loop Gain vs. Frequency
1k
1
VSY = 16V
RL = 10kΩ
AV = 100
10
–30
1k
–90
10M
1M
20
–30
–50
100
100k
FREQUENCY (Hz)
50
VSY = 5V
RL = 10kΩ
07650-025
CLOSED-LOOP GAIN (dB)
30
10k
Figure 24. Open-Loop Gain and Phase vs. Frequency
50
AV = 100
0
–45
Figure 21. Open-Loop Gain and Phase vs. Frequency
40
90
–20
–45
–20
135
07650-022
40
VSY = 16V
RL = 10kΩ
CL = 50pF
60
07650-024
OPEN-LOOP GAIN (dB)
60
180
80
PHASE (Degrees)
VSY = 5V
RL = 10kΩ
CL = 50pF
07650-021
180
80
ADA4665-2
TA = 25°C, unless otherwise noted.
100
100
VSY = 16V
90
80
80
70
70
60
60
50
50
40
100
1k
10k
FREQUENCY (Hz)
100k
1M
40
100
Figure 27. CMRR vs. Frequency
1k
10k
FREQUENCY (Hz)
100k
Figure 30. CMRR vs. Frequency
120
120
VSY = 16V
100
100
80
80
PSRR (dB)
60
40
40
20
PSRR+
PSRR–
–20
100
1k
PSRR+
PSRR–
0
10k
100k
FREQUENCY (Hz)
1M
10M
–20
100
07650-031
0
Figure 28. PSRR vs. Frequency
70
10M
VSY = 16V
VIN = 100mV p-p
RL = 10kΩ
60
OVERSHOOT (%)
OS+
50
40
OS–
50
OS+
40
20
10
10
1k
0
10
07650-032
100
CAPACITANCE (pF)
OS–
30
20
0
10
1M
80
VSY = 5V
VIN = 100mV p-p
RL = 10kΩ
60
30
10k
100k
FREQUENCY (Hz)
Figure 31. PSRR vs. Frequency
80
70
1k
07650-028
20
60
100
CAPACITANCE (pF)
Figure 32. Small Signal Overshoot vs. Load Capacitance
Figure 29. Small Signal Overshoot vs. Load Capacitance
Rev. 0 | Page 10 of 20
1k
07650-029
PSRR (dB)
VSY = 5V
OVERSHOOT (%)
1M
07650-027
CMRR (dB)
90
07650-030
CMRR (dB)
VSY = 5V
ADA4665-2
TA = 25°C, unless otherwise noted.
VSY = 5V
RL = 2kΩ
CL = 10pF
TIME (100µs/DIV)
07650-033
07650-036
VOLTAGE (5V/DIV)
VOLTAGE (1V/DIV)
VSY = 16V
RL = 2kΩ
CL = 10pF
TIME (100µs/DIV)
Figure 33. Large Signal Transient Response
Figure 36. Large Signal Transient Response
VSY = 5V
RL = 2kΩ
CL = 10pF
TIME (100µs/DIV)
TIME (100µs/DIV)
VSY = ±2.5V
0
INPUT
–50
–100
2
1
OUTPUT
0
–1
VSY = ±8V
0
INPUT
–50
–100
10
5
OUTPUT
0
07650-038
3
50
Figure 35. Positive Overload Recovery
–5
TIME (20µs/DIV)
Figure 38. Positive Overload Recovery
Rev. 0 | Page 11 of 20
OUTPUT VOLTAGE (V)
50
07650-035
INPUT VOLTAGE (mV)
Figure 37. Small Signal Transient Response
OUTPUT VOLTAGE (V)
INPUT VOLTAGE (mV)
Figure 34. Small Signal Transient Response
TIME (20µs/DIV)
07650-034
07650-037
VOLTAGE (50mV/DIV)
VOLTAGE (50mV/DIV)
VSY = 16V
RL = 2kΩ
CL = 10pF
ADA4665-2
INPUT VOLTAGE (mV)
150
VSY = ±2.5V
100
50
INPUT
0
150
VSY = ±8V
100
50
INPUT
0
–3
TIME (20µs/DIV)
–5
–10
TIME (20µs/DIV)
Figure 39. Negative Overload Recovery
Figure 42. Negative Overload Recovery
VSY = 16V
RL = 2kΩ
CL = 50pF
OUTPUT
+5mV
0
–5mV
INPUT
OUTPUT
TIME (2µs/DIV)
+5mV
ERROR
BAND
0
–5mV
TIME (2µs/DIV)
Figure 40. Negative Settling Time to 0.1%
Figure 43. Negative Settling Time to 0.1%
INPUT
INPUT
+5mV
TIME (2µs/DIV)
07650-044
0
–5mV
VSY = 16V
RL = 2kΩ
CL = 50pF
OUTPUT
ERROR
BAND
0
–5mV
TIME (2µs/DIV)
Figure 41. Positive Settling Time to 0.1%
Figure 44. Positive Settling Time to 0.1%
Rev. 0 | Page 12 of 20
+5mV
07650-041
OUTPUT
VOLTAGE (500mV/DIV)
VSY = 5V
RL = 2kΩ
CL = 50pF
ERROR
BAND
07650-040
VOLTAGE (500mV/DIV)
INPUT
07650-043
VOLTAGE (500mV/DIV)
VSY = 5V
RL = 2kΩ
CL = 50pF
ERROR
BAND
0
OUTPUT VOLTAGE (V)
–2
OUTPUT
07650-039
–1
07650-042
0
OUTPUT VOLTAGE (V)
OUTPUT
VOLTAGE (500mV/DIV)
INPUT VOLTAGE (mV)
TA = 25°C, unless otherwise noted.
ADA4665-2
TA = 25°C, unless otherwise noted.
100
100
1k
10k
100k
FREQUENCY (Hz)
10
100
07650-048
10
100
1k
10k
100k
FREQUENCY (Hz)
Figure 45. Voltage Noise Density vs. Frequency
Figure 48. Voltage Noise Density vs. Frequency
VSY = 5V
TIME (2s/DIV)
07650-046
07650-049
INPUT VOLTAGE NOISE (1µV/DIV)
INPUT VOLTAGE NOISE (1µV/DIV)
VSY = 16V
TIME (2s/DIV)
Figure 46. 0.1 Hz to 10 Hz Noise
Figure 49. 0.1 Hz to 10 Hz Noise
900
900
+125°C
700
+85°C
600
+25°C
500
–40°C
800
SUPPLY CURRENT (µA)
800
400
300
700
VSY = 16V
600
VSY = 5V
500
200
400
0
0
2
4
6
8
10
SUPPLY VOLTAGE (V)
12
14
16
300
–50
Figure 47. Supply Current vs. Supply Voltage
–25
0
25
50
TEMPERATURE (°C)
75
100
Figure 50. Supply Current vs. Temperature
Rev. 0 | Page 13 of 20
125
07650-050
100
07650-047
SUPPLY CURRENT (µA)
07650-045
VOLTAGE NOISE DENSITY (nV/ Hz)
VSY = 16V
VOLTAGE NOISE DENSITY (nV/ Hz)
VSY = 5V
ADA4665-2
TA = 25°C, unless otherwise noted.
0
1kΩ
CHANNEL SEPARATION (dB)
–20
–40
–60
–80
–100
–120
VIN = 1V p-p
VIN = 4V p-p
1k
10k
–40
–60
–80
–100
–120
100k
VIN = 1V p-p
VIN = 5V p-p
VIN = 15V p-p
–160
100
1k
10k
Figure 53. Channel Separation vs. Frequency
1
VSY = 5V
RL = 10kΩ
AV = 1
THD + NOISE (%)
0.1
0.01
VSY = 16V
RL = 10kΩ
AV = 1
0.1
0.01
VIN = 1V p-p
VIN = 5V p-p
VIN = 15V p-p
VIN = 1V p-p
VIN = 4V p-p
100
1k
FREQUENCY (Hz)
10k
100k
0.001
10
07650-054
0.001
10
100k
FREQUENCY (Hz)
Figure 51. Channel Separation vs. Frequency
THD + NOISE (%)
1kΩ
–140
FREQUENCY (Hz)
1
100kΩ
100
1k
FREQUENCY (Hz)
10k
Figure 54. THD + Noise vs. Frequency
Figure 52. THD + Noise vs. Frequency
Rev. 0 | Page 14 of 20
100k
07650-052
–140
–160
100
VSY = 16V
RL = 10kΩ
AV = –100
100kΩ
07650-053
CHANNEL SEPARATION (dB)
VSY = 5V
RL = 10kΩ
–20
AV = –100
07650-051
0
ADA4665-2
APPLICATIONS INFORMATION
I
RAIL-TO-RAIL INPUT OPERATION
16V
SUPPLY
The ADA4665-2 is a unity-gain stable CMOS operational
amplifier designed with rail-to-rail input/output swing
capability to optimize performance. The rail-to-rail input
feature is vital to maintain the wide dynamic input voltage
range and to maximize signal swing to both supply rails. For
example, the rail-to-rail input feature is extremely useful in
buffer applications where the input voltage must cover both
the supply rails.
RS
0.1Ω
I
R2
1MΩ
VOUT*
RL
R1
10kΩ
16V
1/2
ADA4665-2
The input stage has two input differential pairs, nMOS and
pMOS. When the input common-mode voltage is at the low
end of the input voltage range, the pMOS input differential pair
is active and amplifies the input signal. As the input commonmode voltage is slowly increased, the pMOS differential pair
gradually turns off while the nMOS input differential pair turns
on. This transition is inherent to all rail-to-rail input amplifiers
that use the dual differential pairs topology. For the ADA4665-2,
this transition occurs approximately 1 V away from the positive
rail and results in a change in offset voltage due to the different
offset voltages of the differential pairs (see Figure 5 and Figure 8).
R3
10kΩ
07650-055
R4
1MΩ
*VOUT = AMPLIFIER GAIN × VOLTAGE ACROSS RS
= 100 × RS × I
= 10 × I
Figure 55. Low-Side Current Sensing Circuit
RS
0.1Ω
I
16V
SUPPLY
RL
I
R4
1MΩ
R3
10kΩ
16V
VOUT*
CURRENT SHUNT SENSOR
1/2
ADA4665-2
Figure 55 shows a low-side current sensing circuit, and Figure 56
shows a high-side current sensing circuit using the ADA4665-2.
A typical shunt resistor of 0.1 Ω is used. In these circuits, the
difference amplifier amplifies the voltage drop across the shunt
resistor by a factor of 100. For true difference amplification,
matching of the resistor ratio is very important, where R1/R2 =
R3/R4. The rail-to-rail feature of the ADA4665-2 allows the
output of the op amp to almost reach 16 V (the power supply of
the op amp). This allows the current shunt sensor to sense up to
approximately 1.6 A of current.
R2
1MΩ
R1
10kΩ
*VOUT = AMPLIFIER GAIN × VOLTAGE ACROSS RS
= 100 × RS × I
= 10 × I
07650-056
Many applications require the sensing of signals near the
positive or the negative rails. Current shunt sensors are one
such application and are mostly used for feedback control
systems. They are also used in a variety of other applications,
including power metering, battery fuel gauging, and feedback
controls in electrical power steering. In such applications, it is
desirable to use a shunt with very low resistance to minimize
the series voltage drop. This not only minimizes wasted power,
but also allows the measurement of high currents while saving
power. The ADA4665-2 provides a low cost solution for
implementing current shunt sensors.
Figure 56. High-Side Current Sensing Circuit
ACTIVE FILTERS
The ADA4665-2 is well suited for active filter designs. An active
filter requires an op amp with a unity-gain bandwidth at least
100 times greater than the product of the corner frequency, fc,
and the quality factor, Q. An example of an active filter is the
Sallen-Key, one of the most widely used filter topologies. This
topology gives the user the flexibility of implementing either
a low-pass or a high-pass filter by simply interchanging the
resistors and capacitors. To achieve the desired performance,
1% or better component tolerances are usually required.
Figure 57 shows a two-pole low-pass filter. It is configured as a
unity-gain filter with cutoff frequency at 10 kHz. Resistor and
capacitor values are chosen to give a quality factor, Q, of 1/√2
for a Butterworth filter, which has maximally flat pass-band
frequency response. Figure 58 shows the frequency response of
the low-pass Sallen-Key filter. The response falls off at a rate of
40 dB per decade after the cutoff frequency of 10 kHz.
Rev. 0 | Page 15 of 20
ADA4665-2
C1
1nF
VIN
Figure 59 shows a two-pole high-pass filter, with cutoff frequency
at 10 kHz and quality factor, Q, of 1/√2.
+VSY
R2
22.5kΩ
C1
0.5nF
R1
22.5kΩ
VIN
1/2
VOUT
ADA4665-2
–VSY
C2
0.5nF
07650-057
C2
0.5nF
R2
45kΩ
Figure 57. Two-Pole Low-Pass Filter
fc =
1/2
VOUT
ADA4665-2
–VSY
When R1 = R2 and C1 = 2C2, the values of Q and the cutoff
frequency are calculated as follows:
Q=
+VSY
07650-059
R1
22.5kΩ
Figure 59. Two-Pole High-Pass Filter
When R2 = 2R1 and C1 = C2, the values of Q and the cutoff
frequency are calculated as follows:
R1 R2 C1 C2
C2(R1 + R2)
1
2π R1 R2 C1 C2
Q=
fc =
10
R1 R2 C1 C2
R1(C1 + C2)
1
2π R1 R2 C1 C2
0
10
0
–10
–20
–20
–30
–40
GAIN (dB)
–30
–40
–50
–60
–70
–90
1k
10k
FREQUENCY (Hz)
100k
1M
–100
–110
Figure 58. Low-Pass Filter: Gain vs. Frequency
–120
10
100
1k
10k
FREQUENCY (Hz)
100k
Figure 60. High-Pass Filter: Gain vs. Frequency
Rev. 0 | Page 16 of 20
1M
07650-060
–60
100
–50
–80
07650-058
GAIN (dB)
–10
ADA4665-2
OUTLINE DIMENSIONS
5.00 (0.1968)
4.80 (0.1890)
5
1
4
1.27 (0.0500)
BSC
0.25 (0.0098)
0.10 (0.0040)
6.20 (0.2441)
5.80 (0.2284)
1.75 (0.0688)
1.35 (0.0532)
0.51 (0.0201)
0.31 (0.0122)
COPLANARITY
0.10
SEATING
PLANE
0.50 (0.0196)
0.25 (0.0099)
45°
8°
0°
0.25 (0.0098)
0.17 (0.0067)
1.27 (0.0500)
0.40 (0.0157)
COMPLIANT TO JEDEC STANDARDS MS-012-A A
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
012407-A
8
4.00 (0.1574)
3.80 (0.1497)
Figure 61. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)
3.20
3.00
2.80
8
3.20
3.00
2.80
5
1
5.15
4.90
4.65
4
PIN 1
0.65 BSC
0.95
0.85
0.75
1.10 MAX
0.15
0.00
0.38
0.22
0.23
0.08
COPLANARITY
0.10
0.80
0.60
0.40
8°
0°
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 62. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model
ADA4665-2ARZ 1
ADA4665-2ARZ-RL1
ADA4665-2ARZ-R71
ADA4665-2ARMZ1
ADA4665-2ARMZ-R71
ADA4665-2ARMZ-RL1
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
Package Description
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead MSOP
8-Lead MSOP
8-Lead MSOP
Z = RoHS Compliant Part.
Rev. 0 | Page 17 of 20
Package Option
R-8
R-8
R-8
RM-8
RM-8
RM-8
Branding
A26
A26
A26
ADA4665-2
NOTES
Rev. 0 | Page 18 of 20
ADA4665-2
NOTES
Rev. 0 | Page 19 of 20
ADA4665-2
NOTES
©2009 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D07650-0-1/09(0)
Rev. 0 | Page 20 of 20