Low Power, Rail-to-Rail Output
Precision JFET Amplifier
AD8641/AD8642/AD8643
OUT 1
+IN 3
NC
7
VCC
TOP VIEW
(Not to Scale)
6
OUT
5
NC
NC = NO CONNECT
OUT A 1
–IN A 2
+IN A 3
V– 4
8
V+
AD8642
7
OUT B
TOP VIEW
(Not to Scale)
6
–IN B
5
+IN B
05072-105
Figure 2. 8-Lead SOIC (R-8)
OUT A 1
–IN A 2
AD8642
+IN A 3
TOP VIEW
(Not to Scale)
V– 4
8
V+
7
OUT B
6
–IN B
5
+IN B
05072-064
Figure 3. 8-Lead SOIC (R-8)
Figure 4. 8-Lead MSOP (RM-8)
OUT A 1
14
OUT D
–IN A 2
13
–IN D
12
+IN D
V+ 4
+IN B 5
AD8643
TOP VIEW
11 V–
(Not to Scale)
10 +IN C
–IN B 6
9
–IN C
OUT B 7
8
OUT C
05072-103
+IN A 3
AD8643
TOP VIEW
–IN C 8
+IN B 4
PIN 1
INDICATOR
NC = NO CONNECT
12
–IN D
11
+IN D
10
V–
9
+IN C
05072-104
–IN A 1
+IN A 2
V+ 3
OUT A
OUT D
13 NC
NC
Figure 5. 14-Lead SOIC (R-14)
14
The AD8641/AD8642/AD8643 are fully specified over the
extended industrial temperature range of –40°C to +125°C. The
AD8641 is available in 5-lead SC70 and 8-lead SOIC lead-free
packages. The AD8642 is available in 8-lead MSOP and 8-lead
SOIC lead-free packages. The AD8643 is available in 14-lead
SOIC and 16-lead, 3 mm × 3 mm, LFCSP lead-free packages.
8
AD8641
05072-102
NC 1
–IN 2
16
The AD8641/AD8642/AD8643 are suitable for applications
utilizing multichannel boards that require low power to manage
heat. Other applications include photodiodes, ATE reference
level drivers, battery management, and industrial controls.
–IN
Figure 1. 5-Lead SC70 (KS-5)
–IN B 5
The AD8641/AD8642/AD8643 are low power, precision JFET
input amplifiers 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 DACs, ASICs, and other wide output swing devices in
single-supply systems. The outputs remain stable with
capacitive loads of more than 500 pF.
4
TOP VIEW
(Not to Scale)
+IN 3
APPLICATIONS
GENERAL DESCRIPTION
VCC
05072-101
VEE 2
VEE 4
Line-/battery-powered instruments
Photodiode amplifiers
Precision current sensing
Medical instrumentation
Industrial controls
Precision filters
Portable audio
ATE
5
AD8641
15
Low supply current: 250 µA max
Very low input bias current: 1 pA max
Low offset voltage: 750 µV max
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
SC70 package
PIN CONFIGURATIONS
OUT B 6
OUT C 7
FEATURES
Figure 6. 16-Lead LFCSP (CP-16) (Not Drawn to Scale)
Rev. B
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.
©2005 Analog Devices, Inc. All rights reserved.
AD8641/AD8642/AD8643
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
Conditions
Min
VOS
Typ
Max
Unit
50
750
1
1.5
1.6
1
180
0.5
60
3
93
140
2.5
µV
mV
mV
mV
pA
pA
pA
pA
V
dB
V/mV
µV/°C
0.01
±6
V
V
V
V
mA
AD8643 LFCSP only
–40°C < TA < +85°C
+85°C < TA < +125°C, VCM = 1.5 V
Input Bias Current
IB
0.25
–40°C < TA < +125°C
Input Offset Current
IOS
–40°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
∆VOS/∆T
VCM = 0 V to 2.5 V
RL = 10 kΩ, VO = 0.5 to 4.5 V
–40°C < TA < +125°C
VOH
IL = 1 mA, –40°C to +125°C
Output Voltage Low
0
74
80
4.95
4.94
VOL
IL = 1 mA, –40°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
–40°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
250
270
dB
µA
µA
AD8641, AD8642
AD8643
2
3
2.5
50
V/µs
MHz
MHz
Degrees
f = 0.1 Hz to 10 Hz
f = 1 kHz
f = 1 kHz
4.0
28.5
0.5
µV p-p
nV/√Hz
fA/√Hz
Øm
eN p-p
eN
iN
0.05
0.05
Rev. B | Page 3 of 16
AD8641/AD8642/AD8643
@ VS= ±13 V, VCM = 0 V, TA =25°C, unless otherwise noted.
Table 2.
Parameter
INPUT CHARACTERISTICS
Offset Voltage
Symbol
Conditions
Min
VOS
Typ
Max
Unit
70
750
1
1.5
1
260
0.5
65
+10
107
290
2.5
µV
mV
mV
pA
pA
pA
pA
V
dB
V/mV
µV/°C
±12
V
V
V
V
mA
AD8643 LFCSP only
–40° < TA < +125°C
Input Bias Current
IB
0.25
–40°C < TA < +125°C
Input Offset Current
IOS
–40°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
∆VOS/∆T
VCM = −13 V to +10 V
RL = 10 kΩ, VO = –11 V to +11 V
–40°C < TA < +125°C
VOH
IL = 1 mA, –40°C to +125°C
Output Voltage Low
–13
90
215
+12.95
+12.94
VOL
–12.95
–12.94
IL = 1 mA, –40°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
–40°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. B | Page 4 of 16
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
AD8641/AD8642/AD8643
ABSOLUTE MAXIMUM RATINGS
Table 3.1
Parameter
Supply Voltage
Input Voltage
Differential Input Voltage
Output Short-Circuit Duration
Storage Temperature Range
KS-5, R-8, RM-8, R-14, CP-16 Packages
Operating Temperature Range
Junction Temperature Range
KS-5, R-8, RM-8, R-14, CP-16 Packages
Lead Temperature Range (Soldering, 60 sec)
Rating
27.3 V
VS– to VS+
±Supply Voltage
Indefinite
–65°C to +150°C
–40°C to +125°C
Table 4.
Package Type
5-Lead SC70 (KS)
8-Lead SOIC (R)
8-Lead MSOP (RM)
14-Lead SOIC (R)
16-Lead LFCSP (CP)
1
–65°C to +150°C
300°C
2
θJA2
331.4
157
206
120
44
θJC
223.9
56
44
36
31.5
Unit
°C/W
°C/W
°C/W
°C/W
°C/W
Absolute maximum ratings apply at 25°C, unless otherwise noted.
θJA is specified for the worst-case conditions, that is, θJA is specified for
devices soldered on circuit boards for surface-mounted packages.
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 listed in the operational sections
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. B | Page 5 of 16
AD8641/AD8642/AD8643
OUTLINE DIMENSIONS
2.20
2.00
1.80
1.35
1.25
1.15
5
3.00
BSC
1
2
8
2.40
2.10
1.80
4
3
3.00
BSC
5
4.90
BSC
1
4
PIN 1
0.65 BSC
1.00
0.90
0.70
PIN 1
0.40
0.10
1.10
0.80
0.30
0.15
0.10 MAX
SEATING
PLANE
0.65 BSC
0.22
0.08
1.10 MAX
0.15
0.00
0.30
0.10
0.38
0.22
COPLANARITY
0.10
0.10 COPLANARITY
COMPLIANT TO JEDEC STANDARDS MO-203AA
Figure 46. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
5.00 (0.1968)
4.80 (0.1890)
8
5
0.25 (0.0098)
0.10 (0.0040)
8.75 (0.3445)
8.55 (0.3366)
6.20 (0.2440)
4.00 (0.1575)
3.80 (0.1496)
4 5.80 (0.2284)
1.27 (0.0500)
BSC
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 44. 5-Lead Thin Shrink Small Outline Transistor Package [SC70]
(KS-5)
Dimensions shown in millimeters
4.00 (0.1574)
3.80 (0.1497) 1
0.80
0.60
0.40
8°
0°
0.23
0.08
1.75 (0.0688)
1.35 (0.0532)
0.51 (0.0201)
COPLANARITY
SEATING 0.31 (0.0122)
0.10
PLANE
0.50 (0.0196)
× 45°
0.25 (0.0099)
8°
0.25 (0.0098) 0° 1.27 (0.0500)
0.40 (0.0157)
0.17 (0.0067)
0.25 (0.0098)
0.10 (0.0039)
COPLANARITY
0.10
14
8
1
7
1.27 (0.0500)
BSC
0.51 (0.0201)
0.31 (0.0122)
6.20 (0.2441)
5.80 (0.2283)
1.75 (0.0689)
1.35 (0.0531)
SEATING
PLANE
0.50 (0.0197)
× 45°
0.25 (0.0098)
8°
0.25 (0.0098) 0° 1.27 (0.0500)
0.40 (0.0157)
0.17 (0.0067)
COMPLIANT TO JEDEC STANDARDS MS-012-AA
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
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
Figure 45. 8-Lead Standard Small Outline Package [SOIC_N]
(R-8)
Dimensions shown in millimeters and (inches)
Figure 47. 14-Lead Standard Small Outline Package [SOIC_N]
(R-14)
Dimensions shown in millimeters and (inches)
Rev. B | Page 13 of 16
AD8641/AD8642/AD8643
3.00
BSC SQ
0.60 MAX
13
12
0.45
PIN 1
INDICATOR
TOP
VIEW
2.75
BSC SQ
0.80 MAX
0.65 TYP
12° MAX
SEATING
PLANE
16
1
PIN 1
INDICATOR
*1.65
1.50 SQ
1.35
EXPOSED
PAD
0.50
BSC
0.90
0.85
0.80
0.50
0.40
0.30
9 (BOTTOM VIEW) 4
8
5
0.25 MIN
1.50 REF
0.05 MAX
0.02 NOM
0.30
0.23
0.18
0.20 REF
*COMPLIANT TO JEDEC STANDARDS MO-220-VEED-2
EXCEPT FOR EXPOSED PAD DIMENSION.
Figure 48. 16-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
3 mm × 3 mm Body, Very Thin Quad (CP-16-3)
Dimensions shown in millimeters
ORDERING GUIDE
Model
AD8641AKSZ-R21
AD8641AKSZ-REEL71
AD8641AKSZ-REEL1
AD8641ARZ1
AD8641ARZ-REEL71
AD8641ARZ-REEL1
AD8642ARMZ-R21
AD8642ARMZ-REEL1
AD8642ARZ1
AD8642ARZ-REEL71
AD8642ARZ-REEL1
AD8643ARZ1
AD8643ARZ-REEL71
AD8643ARZ-REEL1
AD8643ACPZ-R21
AD8643ACPZ-REEL71
AD8643ACPZ-REEL1
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
–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
Package Description
5-Lead SC70
5-Lead SC70
5-Lead SC70
8-lead SOIC_N
8-lead SOIC_N
8-lead SOIC_N
8-lead MSOP
8-lead MSOP
8-lead SOIC_N
8-lead SOIC_N
8-lead SOIC_N
14-lead SOIC_N
14-lead SOIC_N
14-lead SOIC_N
16-Lead LFCSP_VQ
16-Lead LFCSP_VQ
16-Lead LFCSP_VQ
Z = Pb-free part.
Rev. B | Page 14 of 16
Package Option
KS-5
KS-5
KS-5
R-8
R-8
R-8
RM-8
RM-8
R-8
R-8
R-8
R-14
R-14
R-14
CP-16-3
CP-16-3
CP-16-3
Branding
A07
A07
A07
A0A
A0A
AUA
AUA
AUA