Analog Devices AD820 Datasheet
Single Supply, Rail to Rail
1
2
3
4
8
7
6
5
TOP VIEW
(Not to Scale)
AD820
NULL
–IN
+IN
–V
S
NC
+V
S
V
OUT
NULL
1
2
3
4
8
7
6
5
TOP VIEW
(Not to Scale)
AD820
NC
–IN
+IN
–V
S
NC
+V
S
V
OUT
NC
NC = NO CONNECT
a
FEATURES
True Single Supply Operation
Output Swings Rail-to-Rail
Input Voltage Range Extends Below Ground
Single Supply Capability from +3 V to +36 V
Dual Supply Capability from ⴞ1.5 V to ⴞ18 V
Excellent Load Drive
Capacitive Load Drive Up to 350 pF
Minimum Output Current of 15 mA
Excellent AC Performance for Low Power
800 A Max Quiescent Current
Unity Gain Bandwidth: 1.8 MHz
Slew Rate of 3.0 V/s
Excellent DC Performance
800 V Max Input Offset Voltage
1 V/ⴗC Typ Offset Voltage Drift
25 pA Max Input Bias Current
Low Noise
13 nV/√Hz @ 10 kHz
APPLICATIONS
Battery Powered Precision Instrumentation
Photodiode Preamps
Active Filters
12- to 14-Bit Data Acquisition Systems
Medical Instrumentation
Low Power References and Regulators
PRODUCT DESCRIPTION
The AD820 is a precision, low power FET input op amp that
can operate from a single supply of +3.0 V to 36 V, or dual
supplies of ±1.5 V to ±18 V. It has true single supply capability
with an input voltage range extending below the negative rail,
50
45
40
35
30
25
20
NUMBER OF UNITS
15
10
5
0
1
0
INPUT BIAS CURRENT – pA
Figure 1. Typical Distribution of Input Bias Current
10
98765432
Low Power FET-Input Op Amp
AD820
CONNECTION DIAGRAMS
8-Lead Plastic Mini-DIP 8-Lead SOIC
allowing the AD820 to accommodate input signals below
ground in the single supply mode. Output voltage swing extends
to within 10 mV of each rail providing the maximum output
dynamic range.
Offset voltage of 800 µV max, offset voltage drift of 1 µV/°C, typ
input bias currents below 25 pA and low input voltage noise
provide dc precision with source impedances up to a Gigaohm.
1.8 MHz unity gain bandwidth, –93 dB THD at 10 kHz and
3 V/µs slew rate are provided for a low supply current of
800 µA. The AD820 drives up to 350 pF of direct capacitive
load and provides a minimum output current of 15 mA. This
allows the amplifier to handle a wide range of load conditions.
This combination of ac and dc performance, plus the outstanding load drive capability, results in an exceptionally versatile
amplifier for the single supply user.
The AD820 is available in three performance grades. The A and
B grades are rated over the industrial temperature range of
–40°C to +85°C. There is 3 V grade—the AD820A-3V, rated
over the industrial temperature range.
The AD820 is offered in two varieties of 8-lead package: plastic
DIP, and surface mount (SOIC).
Figure 2. Gain of +2 Amplifier; VS = +5, 0, VIN = 2.5 V Sine
Centered at 1.25 Volts
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700 World Wide Web Site: http://www.analog.com
Fax: 781/326-8703 © Analog Devices, Inc., 1999
AD820–SPECIFICATIONS
(VS = 0, 5 volts @ TA = +25ⴗC, VCM = 0 V, V
= 0.2 V unless otherwise noted)
OUT
AD820A AD820B
Parameter Conditions Min Typ Max Min Typ Max Units
DC PERFORMANCE
Initial Offset 0.1 0.8 0.1 0.4 mV
Max Offset over Temperature 0.5 1.2 0.5 0.9 mV
Offset Drift 2 2 µV/°C
Input Bias Current VO = 0 V to 4 V 2 25 2 10 pA
at T
MAX
0.5 5 0.5 2.5 nA
Input Offset Current 2 20 2 10 pA
at T
MAX
Open-Loop Gain V
T
to T
MIN
T
MIN
T
MIN
to T
to T
MAX
MAX
MAX
= 0.2 V to 4 V
O
R
= 100k 400 1000 500 1000 V/mV
L
400 400 V/mV
R
= 10k 80 150 80 150 V/mV
L
80 80 V/mV
R
= 1k 15 30 15 30 V/mV
L
10 10 V/mV
0.5 0.5 nA
NOISE/HARMONIC PERFORMANCE
Input Voltage Noise
0.1 Hz to 10 Hz 2 2 µV p-p
f = 10 Hz 25 25 nV/√Hz
f = 100 Hz 21 21 nV/√Hz
f = 1 kHz 16 16 nV/√Hz
f = 10 kHz 13 13 nV/√Hz
Input Current Noise
0.1 Hz to 10 Hz 18 18 fA p-p
f = 1 kHz 0.8 0.8 fA/√Hz
Harmonic Distortion R
= 10k to 2.5 V
L
f = 10 kHz VO = 0.25 V to 4.75 V –93 –93 dB
DYNAMIC PERFORMANCE
Unity Gain Frequency 1.8 1.8 MHz
Full Power Response V
p-p = 4.5 V 210 210 kHz
O
Slew Rate 3 3 V/µs
Settling Time
to 0.1% V
= 0.2 V to 4.5 V 1.4 1.4 µs
O
to 0.01% 1.8 1.8 µs
INPUT CHARACTERISTICS
Common-Mode Voltage Range
T
to T
MIN
CMRR V
T
MIN
Input Impedance
to T
MAX
MAX
Differential 10
Common Mode 1013储2.8 10
OUTPUT CHARACTERISTICS
Output Saturation Voltage
VOL–V
EE
T
to T
MIN
V
CC–VOH
T
MIN
V
OL–VEE
T
MIN
V
CC–VOH
T
MIN
V
OL–VEE
T
MIN
V
CC–VOH
T
MIN
to T
to T
to T
to T
to T
MAX
MAX
MAX
MAX
MAX
MAX
1
–0.2 4 –0.2 4 V
–0.2 4 –0.2 4 V
= 0 V to +2 V 66 80 72 80 dB
CM
66 66 dB
13
储0.5 10
2
I
= 20 µA 5 7 57mV
SINK
13
储0.5 Ω储pF
13
储2.8 Ω储pF
10 10 mV
I
= 20 µA 10 14 1014mV
SOURCE
20 20 mV
I
= 2 mA 40 55 40 55 mV
SINK
80 80 mV
I
= 2 mA 80 110 80 110 mV
SOURCE
160 160 mV
I
= 15 mA 300 500 300 500 mV
SINK
1000 1000 mV
I
= 15 mA 800 1500 800 1500 mV
SOURCE
1900 1900 mV
Operating Output Current 15 15 mA
T
MIN
to T
MAX
12 12 mA
Short Circuit Current 25 25 mA
Capacitive Load Drive 350 350 pF
POWER SUPPLY
Quiescent Current T
Power Supply Rejection V
T
to T
MIN
MAX
to T
MIN
S
MAX
+ = 5 V to 15 V 70 80 66 80 dB
70 66 dB
620 800 620 800 µA
REV. B–2–
(VS = +5 volts @ TA = +25ⴗC, VCM = 0 V, V
= 0 V unless otherwise noted)
OUT
AD820
AD820A AD820B
Parameter Conditions Min Typ Max Min Typ Max Units
DC PERFORMANCE
Initial Offset 0.1 0.8 0.3 0.4 mV
Max Offset over Temperature 0.5 1.5 0.5 1 mV
Offset Drift 2 2 µV/°C
Input Bias Current VCM = –5 V to 4 V 2 25 2 10 pA
at T
MAX
0.5 5 0.5 2.5 nA
Input Offset Current 2 20 2 10 pA
at T
MAX
Open-Loop Gain V
T
to T
MIN
T
MIN
T
MIN
to T
to T
MAX
MAX
MAX
= 4 V to –4 V
O
R
= 100k 400 1000 400 1000 V/mV
L
400 400 V/mV
R
= 10k 80 150 80 150 V/mV
L
80 80 V/mV
R
= 1k 20 30 20 30 V/mV
L
10 10 V/mV
0.5 0.5 nA
NOISE/HARMONIC PERFORMANCE
Input Voltage Noise
0.1 Hz to 10 Hz 2 2 µV p-p
f = 10 Hz 25 25 nV/√Hz
f = 100 Hz 21 21 nV/√Hz
f = 1 kHz 16 16 nV/√Hz
f = 10 kHz 13 13 nV/√Hz
Input Current Noise
0.1 Hz to 10 Hz 18 18 fA p-p
f = 1 kHz 0.8 0.8 fA/√Hz
Harmonic Distortion R
f = 10 kHz V
= 10k
L
= ±4.5 V –93 –93 dB
O
DYNAMIC PERFORMANCE
Unity Gain Frequency 1.9 1.8 MHz
Full Power Response V
p-p = 9 V 105 105 kHz
O
Slew Rate 3 3 V/µs
Settling Time
to 0.1% V
= 0 V to ±4.5 V 1.4 1.4 µs
O
to 0.01% 1.8 1.8 µs
INPUT CHARACTERISTICS
Common-Mode Voltage Range
T
to T
MIN
CMRR V
T
MIN
Input Impedance
to T
MAX
MAX
Differential 10
Common Mode 1013储2.8 10
OUTPUT CHARACTERISTICS
Output Saturation Voltage
VOL–V
EE
T
to T
MIN
V
CC–VOH
T
MIN
V
OL–VEE
T
MIN
V
CC–VOH
T
MIN
V
OL–VEE
T
MIN
V
CC–VOH
T
MIN
to T
to T
to T
to T
to T
MAX
MAX
MAX
MAX
MAX
MAX
1
–5.2 4 –5.2 4 V
–5.2 4 –5.2 4 V
= –5 V to +2 V 66 80 72 80 dB
CM
66 66 dB
13
储0.5 10
2
I
= 20 µA 5 7 57mV
SINK
13
储0.5 Ω储pF
13
储2.8 Ω储pF
10 10 mV
I
= 20 µA 10 14 1014mV
SOURCE
20 20 mV
I
= 2 mA 40 55 40 55 mV
SINK
80 80 mV
I
= 2 mA 80 110 80 110 mV
SOURCE
160 160 mV
I
= 15 mA 300 500 300 500 mV
SINK
1000 1000 mV
I
= 15 mA 800 1500 800 1500 mV
SOURCE
1900 1900 mV
Operating Output Current 15 15 mA
T
MIN
to T
MAX
12 12 mA
Short Circuit Current 30 30 mA
Capacitive Load Drive 350 350 pF
POWER SUPPLY
Quiescent Current T
Power Supply Rejection V
T
to T
MIN
MAX
to T
MIN
S
MAX
+ = 5 V to 15 V 70 80 70 80 dB
70 70 dB
650 800 620 800 µA
–3–REV. B
AD820–SPECIFICATIONS
(VS = ⴞ15 volts @ TA = +25ⴗC, VCM = 0 V, V
= 0 V unless otherwise noted)
OUT
Parameter Conditions Min Typ Max Min Typ Max Units
AD820A AD820B
DC PERFORMANCE
Initial Offset 0.4 2 0.3 1.0 mV
Max Offset over Temperature 0.5 3 0.5 2 mV
Offset Drift 2 2 µV/°C
Input Bias Current V
at T
MAX
Input Offset Current 2 20 2 10 pA
at T
MAX
Open-Loop Gain V
T
to T
MIN
T
MIN
T
MIN
to T
to T
MAX
MAX
MAX
= 0 V 2 25 2 10 pA
CM
= –10 V 40 40 pA
V
CM
VCM = 0 V 0.5 5 0.5 2.5 nA
0.5 0.5 nA
= +10 V to –10 V
O
= 100k 500 2000 500 2000 V/mV
R
L
= 10k 100 500 100 500 V/mV
R
L
= 1k 30 45 30 45 V/mV
R
L
500 500 V/mV
100 100 V/mV
20 20 V/mV
NOISE/HARMONIC PERFORMANCE
Input Voltage Noise
0.1 Hz to 10 Hz 2 2 µV p-p
f = 10 Hz 25 25 nV/√Hz
f = 100 Hz 21 21 nV/√Hz
f = 1 kHz 16 16 nV/√Hz
f = 10 kHz 13 13 nV/√Hz
Input Current Noise
0.1 Hz to 10 Hz 18 18 fA p-p
f = 1 kHz 0.8 0.8 fA/√Hz
Harmonic Distortion R
f = 10 kHz V
= 10k
L
= ±10 V –85 –85 dB
O
DYNAMIC PERFORMANCE
Unity Gain Frequency 1.9 1.9 MHz
Full Power Response V
Slew Rate 3 3 V/µs
p-p = 20 V 45 45 kHz
O
Settling Time
to 0.1% V
= 0 V to ±10 V 4.1 4.1 µs
O
to 0.01% 4.5 4.5 µs
INPUT CHARACTERISTICS
Common-Mode Voltage Range
to T
T
MIN
MAX
CMRR V
to T
T
MIN
MAX
Input Impedance
Differential 10
Common Mode 1013储2.8 10
OUTPUT CHARACTERISTICS
Output Saturation Voltage
VOL–V
EE
to T
T
MIN
MIN
MIN
MIN
MIN
MIN
to T
to T
to T
to T
to T
MAX
MAX
MAX
MAX
MAX
MAX
V
CC–VOH
T
V
OL–VEE
T
V
CC–VOH
T
V
OL–VEE
T
V
CC–VOH
T
1
–15.2 14 –15.2 14 V
–15.2 14 –15.2 14 V
= –15 V to 12 V 70 80 74 90 dB
CM
70 74 dB
13
储0.5 10
2
I
= 20 µA 5 7 57mV
SINK
13
储0.5 Ω储pF
13
储2.8 Ω储pF
10 10 mV
I
= 20 µA 10 14 1014mV
SOURCE
20 20 mV
I
= 2 mA 40 55 40 55 mV
SINK
80 80 mV
I
= 2 mA 80 110 80 110 mV
SOURCE
160 160 mV
I
= 15 mA 300 500 300 500 mV
SINK
1000 1000 mV
I
= 15 mA 800 1500 800 1500 mV
SOURCE
1900 1900 mV
Operating Output Current 20 20 mA
to T
T
MIN
MAX
15 15 mA
Short Circuit Current 45 45 mA
Capacitive Load Drive 350 350
POWER SUPPLY
Quiescent Current T
Power Supply Rejection V
T
to T
MIN
MAX
to T
MIN
S
MAX
+ = 5 V to 15 V 70 80 70 80 dB
70 70 dB
700 900 700 900 µA
–4–
REV. B
(VS = 0, 3 volts @ TA = +25ⴗC, VCM = 0 V, V
= 0.2 V unless otherwise noted)
OUT
AD820
AD820A-3V
Parameter Conditions Min Typ Max Units
DC PERFORMANCE
Initial Offset 0.2 1 mV
Max Offset over Temperature 0.5 1.5 mV
Offset Drift 1 µV/°C
Input Bias Current V
at T
MAX
= 0 V to +2 V 2 25 pA
CM
0.5 5 nA
Input Offset Current 220 pA
at T
MAX
Open-Loop Gain V
T
to T
MIN
T
MIN
T
MIN
to T
to T
MAX
MAX
MAX
= 0.2 V to 2 V
O
R
= 100k 300 1000 V/mV
L
400 V/mV
R
= 10k 60 150 V/mV
L
80 V/mV
R
= 1k 10 30 V/mV
L
8 V/mV
0.5 nA
NOISE/HARMONIC PERFORMANCE
Input Voltage Noise
0.1 Hz to 10 Hz 2 µV p-p
f = 10 Hz 25 nV/√Hz
f = 100 Hz 21 nV/√Hz
f = 1 kHz 16 nV/√Hz
f = 10 kHz 13 nV/√Hz
Input Current Noise
0.1 Hz to 10 Hz 18 fA p-p
f = 1 kHz 0.8 fA/√Hz
Harmonic Distortion R
f = 10 kHz V
= 10k to 1.5 V
L
= ±1.25 V –92 dB
O
DYNAMIC PERFORMANCE
Unity Gain Frequency 1.5 MHz
Full Power Response V
p-p = 2.5 V 240 kHz
O
Slew Rate 3V/µs
Settling Time
to 0.1% V
= 0.2 V to 2.5 V 1 µs
O
to 0.01% 1.4 µs
INPUT CHARACTERISTICS
Common-Mode Voltage Range
T
to T
MIN
MAX
CMRR V
T
to T
MIN
MAX
Input Impedance
Differential 10
Common Mode 10
OUTPUT CHARACTERISTICS
Output Saturation Voltage
VOL–V
EE
T
to T
MIN
V
CC–VOH
T
MIN
V
OL–VEE
T
MIN
V
CC–VOH
T
MIN
V
OL–VEE
T
MIN
V
CC–VOH
T
MIN
to T
to T
to T
to T
to T
MAX
MAX
MAX
MAX
MAX
MAX
1
–0.2 2 V
–0.2 2 V
= 0 V to +1 V 60 74 dB
CM
60 dB
13
储0.5 Ω储pF
13
储2.8 Ω储pF
2
I
= 20 µA57mV
SINK
10 mV
I
= 20 µA1014mV
SOURCE
20 mV
I
= 2 mA 40 55 mV
SINK
80 mV
I
= 2 mA 80 110 mV
SOURCE
160 mV
I
= 10 mA 200 400 mV
SINK
400 mV
I
= 10 mA 500 1000 mV
SOURCE
1000 mV
Operating Output Current 15 mA
T
MIN
to T
MAX
12 mA
Short Circuit Current 18 25 mA
T
MIN
to T
MAX
15 mA
Capacitive Load Drive 350 pF
POWER SUPPLY
Quiescent Current T
Power Supply Rejection V
T
to T
MIN
MAX
to T
MIN
S
MAX
+ = 3 V to 15 V 70 80 dB
620 800 µA
70 dB
REV. B
–5–
Loading...