AD8643-EP Data Sheet

Low Power, Rail-to-Rail,
Output Precision JFET Amplifier
AD8643-EP
Low supply current: 250 μA maximum
Very low input bias current: 1 pA maximum
Low offset voltage: 750 μV maximum
Single-supply operation: 5 V to 26 V
Dual-supply operation: ±2.5 V to ±13 V
Rail-to-rail output
Unity-gain stable
No phase reversal
PIN CONFIGURATION
OUT A 1
14
OUT D
–IN A 2
13
–IN D
AD8643-EP
12
+IN D
TOP VIEW
(Not to Scale)
11
V–
10
+IN C
–IN B 6
9
–IN C
OUT B 7
8
OUT C
+IN A 3
V+ 4
+IN B 5
09590-103
FEATURES
Figure 1. 14-Lead SOIC (R-14)
ENHANCED PRODUCT FEATURES
Supports defense and aerospace applications
(AQEC standard)
Military temperature range (−55°C to +125°C)
Controlled manufacturing baseline
1 assembly/test site
1 fabrication site
Enhanced product change notification
Qualification data available on request
APPLICATIONS
Line-/battery-powered instruments
Photodiode amplifiers
Precision current sensing
Precision filters
Portable audio
GENERAL DESCRIPTION
The AD8643-EP is a low power, precision JFET input amplifier
featuring extremely low input bias current and rail-to-rail output.
The ability to swing nearly rail-to-rail at the input and rail-to-rail at
the output enables designers to buffer CMOS digital-to-analog
converters (DACs), ASICs, and other wide output swing devices
in single-supply systems. The outputs remain stable with capacitive
loads of more than 500 pF.
The AD8643-EP is suitable for applications using multichannel
boards that require low power to manage heat. Other applications
include photodiodes and battery management.
The AD8643-EP is fully specified over the military temperature
range of −55°C to +125°C. This device is available in a 14-lead SOIC.
Additional applications information is available in the AD8643
data sheet.
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
©2011 Analog Devices, Inc. All rights reserved.
AD8643-EP
TABLE OF CONTENTS
Features .............................................................................................. 1 Electrical Characteristics..............................................................3 Enhanced Product Features ............................................................ 1 Absolute Maximum Ratings ............................................................5 Applications....................................................................................... 1 Thermal Resistance .......................................................................5 Pin Configuration............................................................................. 1 ESD Caution...................................................................................5 General Description ......................................................................... 1 Typical Performance Characteristics ..............................................6 Revision History ............................................................................... 2 Outline Dimensions ....................................................................... 12 Specifications..................................................................................... 3 Ordering Guide .......................................................................... 12 REVISION HISTORY
1/11—Revision 0: Initial Version
Rev. 0 | Page 2 of 12
AD8643-EP
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS
VS = 5.0 V, VCM = 2.5 V, TA = 25°C, unless otherwise noted.
Table 1.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Test Conditions/Comments
Min
VOS
Typ
Max
Unit
50
1000
1.8
1.9
1
180
0.5
60
3
93
140
2.5
μV
mV
mV
pA
pA
pA
pA
V
dB
V/mV
μV/°C
0.01
±6
V
V
V
V
mA
−55°C < TA < +85°C
+85°C < TA < +125°C, VCM = 1.5 V
Input Bias Current
IB
0.25
−55°C < TA < +125°C
Input Offset Current
IOS
−55°C < TA < +125°C
Input Voltage Range
Common-Mode Rejection Ratio
Large Signal Voltage Gain
Offset Voltage Drift
OUTPUT CHARACTERISTICS
Output Voltage High
CMRR
AVO
ΔVOS/ΔT
VCM = 0 V to 2.5 V
RL = 10 kΩ, VO = 0.5 to 4.5 V
−55°C < TA < +125°C
VOH
IL = 1 mA, −55°C to +125°C
Output Voltage Low
0
74
80
4.95
4.94
VOL
IL = 1 mA, −55°C to +125°C
Output Current
POWER SUPPLY
Power Supply Rejection Ratio
Supply Current/Amplifier
IOUT
PSRR
ISY
VS = 5 V to 26 V
90
107
195
−55°C < TA < +125°C
DYNAMIC PERFORMANCE
Slew Rate
Gain Bandwidth Product
Phase Margin
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
SR
GBP
Øm
eN p-p
eN
iN
f = 0.1 Hz to 10 Hz
f = 1 kHz
f = 1 kHz
Rev. 0 | Page 3 of 12
0.05
0.05
250
270
dB
μA
μA
2
2.5
50
V/μs
MHz
Degrees
4.0
28.5
0.5
μV p-p
nV/√Hz
fA/√Hz
AD8643-EP
VS= ±13 V, VCM = 0 V, TA = 25°C, unless otherwise noted.
Table 2.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Test Conditions/Comments
Min
VOS
Typ
Max
Unit
70
1000
1.8
1
260
0.5
65
+10
107
290
2.5
μV
mV
pA
pA
pA
pA
V
dB
V/mV
μV/°C
±12
V
V
V
V
mA
−55° < TA < +125°C
Input Bias Current
IB
0.25
–55°C < TA < +125°C
Input Offset Current
IOS
−55°C < TA < +125°C
Input Voltage Range
Common-Mode Rejection Ratio
Large Signal Voltage Gain
Offset Voltage Drift
OUTPUT CHARACTERISTICS
Output Voltage High
CMRR
AVO
ΔVOS/ΔT
VCM = −13 V to +10 V
RL = 10 kΩ, VO = –11 V to +11 V
−55°C < TA < +125°C
VOH
IL = 1 mA, −55°C to +125°C
Output Voltage Low
−13
90
215
12.95
12.94
VOL
−12.95
−12.94
IL = 1 mA, −55°C to +125°C
Output Current
POWER SUPPLY
Power Supply Rejection Ratio
Supply Current/Amplifier
IOUT
PSRR
ISY
VS = ±2.5 V to ±13 V
90
107
200
−55°C < TA < +125°C
DYNAMIC PERFORMANCE
Slew Rate
Gain Bandwidth Product
Phase Margin
NOISE PERFORMANCE
Voltage Noise
Voltage Noise Density
Current Noise Density
SR
GBP
Øm
eN p-p
eN
iN
f = 0.1 Hz to 10 Hz
f = 1 kHz
f = 1 kHz
Rev. 0 | Page 4 of 12
290
330
dB
μA
μA
3
3.5
60
V/μs
MHz
Degrees
4.2
27.5
0.5
μV p-p
nV/√Hz
fA/√Hz
AD8643-EP
ABSOLUTE MAXIMUM RATINGS
Absolute maximum ratings apply at 25°C, unless otherwise noted.
THERMAL RESISTANCE
Table 3.
θJA is specified for the worst-case conditions, that is, a device
soldered in a circuit board for surface-mount packages.
Parameter
Supply Voltage
Input Voltage
Differential Input Voltage
Output Short-Circuit Duration
Storage Temperature Range
Operating Temperature Range
Junction Temperature Range
Lead Temperature (Soldering, 60 sec)
Rating
27.3 V
V− to V+
±Supply Voltage
Indefinite
−65°C to +150°C
−55°C to +125°C
−65°C to +150°C
300°C
Table 4. Thermal Resistance
Package Type
14-Lead SOIC (R)
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. 0 | Page 5 of 12
θJA
120
θJC
36
Unit
°C/W
AD8643-EP
TYPICAL PERFORMANCE CHARACTERISTICS
80
20
VSY = ±13V
VSY = 5V
VCM = 1.5V
18
70
16
NUMBER OF AMPLIFIERS
FREQUENCY
60
50
40
30
20
14
12
10
8
6
09590-005
9.5
10.0
9.0
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
TCVOS (μV/°C)
Figure 2. Input Offset Voltage
Figure 5. Offset Voltage Drift
16
4.5
VSY = ±13V
VSY = ±13V
TA = 25°C
4.0
14
3.5
12
3.0
INPUT BIAS (pA)
NUMBER OF AMPLIFIERS
2.5
2.0
1.5
09590-002
VOS (mV)
1.0
0
0
0
–0.60
–0.55
–0.50
–0.45
–0.40
–0.35
–0.30
–0.25
–0.20
–0.15
–0.10
–0.05
0
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
2
0.5
4
10
10
8
6
2.5
2.0
1.5
1.0
4
0.5
2
0
–9
–7
–5
–3
–1
1
3
5
7
9
11
13
15
09590-006
–15 –13 –11
150
09590-008
OFFSET VOLTAGE (μV/°C)
–0.5
09590-003
9.5
10.0
9.0
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0
0.5
0
VCM (V)
Figure 6. Input Bias Current vs. VCM
Figure 3. Offset Voltage Drift
1000
70
VSY = ±13V
VSY = ±2.5V
INPUT BIAS CURRENT (pA)
60
40
30
20
100
10
1
10
0.1
VOS (mV)
09590-004
0
–0.60
–0.55
–0.50
–0.45
–0.40
–0.35
–0.30
–0.25
–0.20
–0.15
–0.10
–0.05
0
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
FREQUENCY
50
0
25
50
75
100
125
TEMPERATURE (°C)
Figure 7. Input Bias Current vs. Temperature
Figure 4. Input Offset Voltage
Rev. 0 | Page 6 of 12
AD8643-EP
1.0
10M
VSY = +5V OR ±5V
0.8
OPEN-LOOP GAIN (V/V)
0.6
INPUT BIAS (pA)
0.4
0.2
0
–0.2
–0.4
1M
VSY = ±13V
VSY = ±2.5V
100k
–0.6
–1.0
–4
–3
–2
–1
0
1
2
3
4
5
VCM (V)
10k
0.1
09590-009
–5
1
Figure 8. Input Bias Current vs. VCM
1000
900
100
Figure 11. Open-Loop Gain vs. Load Resistance
1000
VSY = ±13V
A
800
B
C
700
100
D
AVO (V/mV)
600
VOS (μV)
10
09590-012
–0.8
500
400
300
E
10
200
0
–15 –13 –11
–9
–7
–5
–3
–1
1
3
5
7
9
11
13
VCM (V)
15
09590-010
–100
1
–70
–50
–30
–10
10
30
50
70
90
110
130
150
TEMPERATURE (°C)
Figure 9. Input Offset Voltage (VOS) vs. VCM
09590-013
A. VSY = ±13V, VO = ±11V, RL = 10kΩ
B. VSY = ±13V, VO = ±11V, RL = 2kΩ
C. VSY = +5V, VO = +0.5V/+4.5V, RL = 10kΩ
D. VSY = +5V, VO = +0.5V/+4.5V, RL = 2kΩ
E. VSY = +5V, VO = +0.5V/+4.5V, RL = 600Ω
100
Figure 12. Open-Loop Gain vs. Temperature
600
500
VSY = 5V
500
400
VSY = ±13V
400
300
300
200
100
100
0
0
–100
–100
–200
–200
–300
–300
–400
–400
0
0.5
1.0
1.5
2.0
VCM (V)
2.5
–600
–15
–10
–5
0
5
10
15
OUTPUT VOLTAGE (V)
Figure 13. Input Error Voltage vs. Output Voltage for Resistive Loads
Figure 10. Input Offset Voltage vs. VCM
Rev. 0 | Page 7 of 12
09590-014
–500
–500
09590-011
VOS (μV)
200
AD8643-EP
10000
250
VSY = ±5V
200
VSY = 5V
POS RAIL
VSY – VOH
RL = 2kΩ
0
RL = 10kΩ
RL = 100kΩ
–50
–100
–150
–200
RL = 100kΩ RL = 1kΩ
RL = 10kΩ
NEG RAIL
RL = 2kΩ
–300
–350
0
50
100
150
200
250
300
350
OUTPUT VOLTAGE FROM SUPPLY RAIL (mV)
VOL
100
10
1
0.001
09590-015
–250
1000
0.01
0.1
1
10
100
LOAD CURRENT (mA)
Figure 17. Output Saturation Voltage vs. Load Current
Figure 14. Input Error Voltage vs. Output Voltage
Within 300 mV of Supply Rails
800
70
VSY = ±13V
RL = 2kΩ
CL = 40pF
60
700
50
600
315
270
225
40
180
500
GAIN (dB)
GAIN
400
+25°C
300
09590-018
RL = 1kΩ
50
30
135
20
PHASE
45
0
0
+125°C
200
–55°C
90
10
–10
–45
–20
–90
PHASE (Degrees)
100
SATURATION VOLTAGE (mV)
INPUT VOLTAGE (μV)
150
100
8
12
16
20
24
28
VSY (V)
–30
10k
09590-016
4
1M
10M
FREQUENCY (Hz)
Figure 15. Quiescent Current vs. Supply Voltage at Different Temperatures
Figure 18. Open-Loop Gain and Phase Margin vs. Frequency
70
10000
VSY = ±13V
315
VSY = 5V
RL = 2kΩ
CL = 40pF
60
VSY – VOH
50
270
225
GAIN (dB)
40
100
–VSY – VOL
180
GAIN
30
135
20
90
PHASE
10
45
0
0
PHASE (Degrees)
1000
1
0.001
0.01
0.1
1
10
LOAD CURRENT (mA)
100
Figure 16. Output Saturation Voltage vs. Load Current
–10
–45
–20
–90
–30
10k
–135
100k
1M
10M
FREQUENCY (Hz)
Figure 19. Open-Loop Gain and Phase Margin vs. Frequency
Rev. 0 | Page 8 of 12
09590-020
10
09590-017
SATURATION VOLTAGE (mV)
–135
100k
09590-019
0
AD8643-EP
70
140
VSY = ±13V
RL = 2kΩ
CL = 40pF
60
50
120
VSY = 5V
100
40
80
30
CMRR (dB)
20
G = +10
10
0
60
40
20
–20
–20
–40
10k
100k
1M
–60
1k
09590-021
10M
FREQUENCY (Hz)
10k
Figure 20. Closed-Loop Gain vs. Frequency
140
60
120
50
100
40
80
PSRR (dB)
GAIN (dB)
G = +100
30
20
G = +10
10
0
10M
VSY = ±13V
+PSRR
60
–PSRR
40
20
0
G = +1
–10
–20
–20
–40
100k
1M
–60
1k
09590-022
10k
10M
FREQUENCY (Hz)
10k
100k
1M
10M
10M
FREQUENCY (Hz)
Figure 24. PSRR vs. Frequency
Figure 21. Closed-Loop Gain vs. Frequency
140
140
120
1M
Figure 23. CMRR vs. Frequency
70
–30
1k
100k
FREQUENCY (Hz)
09590-025
–30
1k
09590-024
0
G = +1
–10
09590-026
GAIN (dB)
G = +100
VSY = ±13V
120
100
100
80
80
60
60
VSY = 5V
PSRR (dB)
40
20
40
0
–20
–20
–40
–40
–60
1k
10k
100k
1M
FREQUENCY (Hz)
10M
–PSRR
20
0
09590-023
CMRR (dB)
+PSRR
–60
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 25. PSRR vs. Frequency
Figure 22. CMRR vs. Frequency
Rev. 0 | Page 9 of 12
AD8643-EP
1000
15
VSY = ±13V
VS = ±13V
GAIN = +5
G = +100
10
TS + (1%)
10
G = +10
1
G = +1
0.1
5
TS + (0.1%)
0
–5
TS – (0.1%)
–10
1k
10k
100k
1M
10M
100M
FREQUENCY (Hz)
–15
09590-027
0.01
TS – (1%)
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
SETTLING TIME (μs)
09590-030
OUTPUT SWING (V)
ZOUT (Ω)
100
Figure 29. Output Swing and Error vs. Settling Time
Figure 26. Output Impedance vs. Frequency
70
1000
VS = ±13V
RL = 10kΩ
VIN = 100mV p-p
AV = +1
VSY = 5V
G = +100
60
100
OVERSHOOT (%)
10
G = +10
1
G = +1
40
OS–
30
OS+
20
0.1
10
100k
1M
10M
100M
FREQUENCY (Hz)
0
1
100
1000
1000
CAPACITANCE (pF)
Figure 27. Output Impedance vs. Frequency
T
10
09590-031
10k
09590-032
1k
09590-028
0.01
Figure 30. Small Signal Overshoot vs. Load Capacitance
70
VSY = ±13V
VS = ±2.5V
RL = 10kΩ
VIN = 100mV p-p
AV = +1
60
1
VIN
OVERSHOOT (%)
50
40
OS–
30
OS+
20
2
VOUT
10
CH1 10.0V
CH2 10.0V
M400μs
A CH1
T
0.00000s
1.00V
09590-029
ZOUT (Ω)
50
0
1
10
100
CAPACITANCE (pF)
Figure 31. Small Signal Overshoot vs. Load Capacitance
Figure 28. No Phase Reversal
Rev. 0 | Page 10 of 12
AD8643-EP
1k
VS = ±13V
G = +1M
CH1 p-p = 4.26V
VOLTAGE NOISE DENSITY (nV/ Hz)
VSY = 5V
M1.00s
A CH1
–20.0V
10
1
10
100
1k
10k
FREQUENCY (Hz)
Figure 32. 0.1 Hz to 10 Hz Noise
09590-036
CH1 1.00V
09590-033
1
100
Figure 35. Voltage Noise Density
0.004
VS = ±2.5V
G = +1M
CH1 p-p = 4.06V
VSY = ±13V
LOAD = 100kΩ
GAIN = +1
THD + NOISE (%)
0.001
1
8V p-p INPUT
1V p-p INPUT
2V p-p INPUT
0.0001
4V p-p INPUT
M1.00s
A CH1
–20.0V
0.000001
1
100
1k
10k
20k
FREQUENCY (Hz)
Figure 33. 0.1 Hz to 10 Hz Noise
Figure 36. Total Harmonic Distortion + Noise vs. Frequency
–40
VSY = ±13V
20kΩ
–50
2kΩ
–
–60
–
+
–70
VIN
2kΩ
2kΩ
+
–80
100
(dB)
–90
VIN = 18V p-p
–100
–110
–120
10
VIN = 4.5V p-p
–130
–140
–160
1
10
100
1k
FREQUENCY (Hz)
10k
20
100
1k
10k
FREQUENCY (Hz)
Figure 37. Channel Separation
Figure 34. Voltage Noise Density
Rev. 0 | Page 11 of 12
100k
09590-041
VIN = 9V p-p
–150
09590-035
VOLTAGE NOISE DENSITY (nV/ Hz)
1k
09590-037
CH1 1.00V
09590-034
0.00001
AD8643-EP
OUTLINE DIMENSIONS
8.75 (0.3445)
8.55 (0.3366)
8
14
1
7
1.27 (0.0500)
BSC
0.25 (0.0098)
0.10 (0.0039)
COPLANARITY
0.10
0.51 (0.0201)
0.31 (0.0122)
6.20 (0.2441)
5.80 (0.2283)
0.50 (0.0197)
0.25 (0.0098)
1.75 (0.0689)
1.35 (0.0531)
SEATING
PLANE
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-AB
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.
060606-A
4.00 (0.1575)
3.80 (0.1496)
Figure 38. 14-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-14)
Dimensions shown in millimeters and (inches)
ORDERING GUIDE
Model 1
AD8643TRZ-EP
AD8643TRZ-EP-R7
1
Temperature Range
−55°C to +125°C
−55°C to +125°C
Package Description
14-lead SOIC_N
14-lead SOIC_N
Z = RoHS Compliant Part.
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09590-0-1/11(0)
Rev. 0 | Page 12 of 12
Package Option
R-14
R-14
Similar pages