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DVANCED
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INEAR
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EVICES,
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NC.
ALD2704A/ALD2704B
ALD2704
DUAL RAIL-TO-RAIL CMOS OPERATIONAL AMPLIFIER
GENERAL DESCRIPTION
The ALD2704A/ALD2704B/ALD2704 is a dual monolithic operational
amplifier with MOSFET input that has rail-to-rail input and output voltage
ranges. The input voltage range and output voltage range are very close
to the positive and negative power supply voltages. Typically the input
voltage can be beyond positive power supply voltage V+ or the negative
power supply voltage V- by up to 300mV. The output voltage swings to
within 60mV of either positive or negative power supply voltages at rated
load.
With high impedance load, the output voltage of the ALD2704A/ALD2704B/
ALD2704 approaches within 1mV of the power supply rails. This device
is designed as an alternative to the popular J-FET input operational
amplifier in applications where lower operating voltages, such as 9V
battery or
±3.25V
to
±5V
power supplies are being used. The ALD2704A/
ALD2704B/ALD2704 offers high slew rate of 5V/µs. It is designed and
manufactured with Advanced Linear Devices' standard enhanced ACMOS
silicon gate CMOS process, and it offers low unit cost and exceptional
reliability.
The rail-to-rail input and output feature of the ALD2704A/ALD2704B/
ALD2704 expands signal voltage range for a given operating supply
voltage and allows numerous analog serial stages to be implemented
without losing operating voltage margin. The output stage is designed to
drive up to 10mA into 400pF capacitive and 1.5KΩ resistive loads at unity
gain and up to 4000pF at a gain of 5. Short circuit protection to either
ground or the power supply rails is at approximately 15mA clamp current.
Due to complementary output stage design, the output can source and
sink 10mA into a load with symmetrical drive and is ideally suited for
applications where push-pull voltage drive is desired.
For each of the operational amplifier, the offset voltage is trimmed on-chip
to eliminate the need for external nulling in many applications. For
precision applications, the output is designed to settle to 0.1% in 2µs. In
large signal buffer applications, the operational amplifier can function as
an ultrahigh input impedance voltage follower /buffer that allows input and
output voltage swings from positive to negative supply voltages. This
feature is intended to greatly simplify systems design and eliminate higher
voltage power supplies in many applications. Additionally, robust design
and rigorous screening make this device especially suitable for operation
in temperature-extreme environments and rugged conditions.
ORDERING INFORMATION
(“L” suffix denotes lead-free (RoHS))
Operating Temperature Range
0°C to +70°C
0°C to +70°C
-55°C to 125°C
8-Pin
Small Outline
Package (SOIC)
ALD2704ASAL
ALD2704BSAL
ALD2704SAL
8-Pin
Plastic Dip
Package
ALD2704APAL
ALD2704BPAL
ALD2704PAL
8-Pin
CERDIP
Package
ALD2704ADA
ALD2704BDA
ALD2704DA
FEATURES
•
•
•
•
•
•
•
•
•
•
•
•
Rail-to-rail input and output voltage ranges
Symmetrical push-pull output drives
Output settles to 2mV of supply rails
5.0V/µs slew rate
High capacitive load capability -- up to 4000pF
No frequency compensation required -- unity
gain stable
Extremely low input bias currents -- <1.0pA
typical (20pA max.)
Ideal for high source impedance applications
High voltage gain -- typically 100V/mV
Output short circuit protected
Unity gain bandwidth of 2.1MHz
Suitable for rugged, temperature-extreme
environments
APPLICATIONS
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Voltage amplifier
Voltage follower/buffer
Charge integrator
Photodiode amplifier
Data acquisition systems
High performance portable instruments
Signal conditioning circuits
Low leakage amplifiers
Active filters
Sample/Hold amplifier
Picoammeter
Current to voltage converter
Coaxial cable driver
Capacitive sensor amplifier
Piezoelectric transducer amplifier
PIN CONFIGURATION
V+
OUT
B
-IN
B
+IN
B
OUT
A
-IN
A
+IN
A
V-
1
2
3
4
TOP VIEW
SAL, PAL, DA PACKAGES
8
7
6
5
* Contact factory for leaded (non-RoHS) or high temperature versions.
Rev 2.0 ©2010 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, CA 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286
www.aldinc.com
ABSOLUTE MAXIMUM RATINGS
Supply voltage, V
+
referenced to V
-
Supply voltage, V
S
referenced to V
-
Differential input voltage range
Power dissipation
Operating tempurature range SAL, PAL packages
DA package
Storage tempurature range
Lead tempurature, 10 seconds
CAUTION:
ESD Sensitive Device. Use static control procedures in ESD controlled environment.
-0.3V to V++10.6V
±5.3V
-0.3V to V+ +0.3V
600 mW
0°C to +70°C
-55°C to +125°C
-65°C to +150°C
+260°C
OPERATING ELECTRICAL CHARACTERISTICS
T
A
= 25
°
C V
S
=
±
5.0V unless otherwise specified
Parameter
Supply
Voltage
Input Offset
Voltage
Input Offset
Current
Input Bias
Current
Input Voltage
Range
Input
Resistance
Input Offset
Voltage Drift
Power Supply
Rejection Ratio
Common Mode
Rejection Ratio
Large Signal
Voltage Gain
Output
Voltage
Range
Symbol
V
S
V
+
V
OS
I
OS
I
B
V
IR
R
IN
TCV
OS
PSRR
65
-5.3
1.0
1.0
2704A
Min Typ
±3.25
6.5
Max
2704B
Min Typ Max
2704
Min Typ
Max
±5.0
10.0
5.0
6.0
1.0
1.0
-5.3
15
240
20
300
5.3
Unit
V
V
mV
mV
pA
pA
pA
pA
V
Test
Conditions
Dual Supply
Single Supply
R
S
≤
100KΩ
0°C
≤
T
A
≤
+70°C
T
A
= 25°C
0°C
≤
T
A
≤
+70°C
T
A
= 25°C
0°C
≤
T
A
≤
+70°C
±5.0 ±3.25
10.0
6.5
1.0
1.5
15
240
20
300
5.3
-5.3
1.0
1.0
±5.0 ±3.25
10.0
6.5
2.0
3.0
15
240
20
300
5.3
10
12
10
12
10
12
Ω
5
80
65
5
80
60
5
80
µV/°C
dB
R
S
≤
100KΩ
R
S
≤
100KΩ
0°C
≤
T
A
≤
+70°C
R
S
≤
100KΩ
0°C
≤
T
A
≤
+70°C
R
L
= 100KΩ
R
L
≥
1MΩ
R
L
≥
10KΩ
0°C
≤
T
A
≤
+70°C
R
L
= 1MΩ
0°C
≤
T
A
≤
+70°C
CMRR
65
83
65
83
60
83
dB
A
V
15
28
100
15
28
100
10
28
100
V/mV
V/mV
V
O
low
V
O
high
V
O
low
V
O
high
I
SC
I
S
P
D
4.90
4.99
-4.96 -4.90
-4.96 -4.90
-4.96 -4.90
4.95
4.90 4.95
4.90 4.95
-4.998 -4.99
-4.998 -4.99
-4.998 -4.99
4.998
4.99 4.998
4.99 4.998
15
5.0
6.5
15
5.0
6.5
15
5.0
6.5
V
V
mA
mA
Output Short
Circuit Current
Supply
Current
Power
Dissipation
Input
Capacitance
Bandwidth
Slew Rate
Rise time
Overshoot
Factor
V
IN
= -5V
No Load
Both amplifiers, No Load
V
S
=
±5.0V
65
65
65
mW
C
IN
1
1
1
pF
B
W
S
R
t
r
2.1
5.0
0.1
15
2.1
5.0
0.1
15
2.1
5.0
0.1
15
MHz
V/µs
µs
%
A
V
= +1 R
L
= 2.0KΩ
R
L
= 2.0KΩ
R
L
= 2.0KΩ
C
L
= 100pF
ALD2704A/ALD2704B
ALD2704
Advanced Linear Devices
2 of 9
OPERATING ELECTRICAL CHARACTERISTICS (cont'd)
T
A
= 25
°
C V
S
=
±
5.0V unless otherwise specified
2704A
Parameter
Maximum Load
Capacitance
Symbol
C
L
Min
Typ
400
4000
Max
Min
2704B
Typ
400
4000
Max
Min
2704
Typ
400
4000
Max
Unit
pF
pF
Test Conditions
Gain = 1
Gain = 5
Input Noise
Voltage
e
n
26
26
26
nV/√Hz
f =1KHz
Input Current
Noise
i
n
0.6
0.6
0.6
fA/√Hz
f =10Hz
Settling
Time
t
s
5.0
2.0
5.0
2.0
5.0
2.0
µs
µs
0.01%
0.1% A
V
= 1
R
L
= 5KΩ C
L
= 50pF
V
S
=
±
5.0V -55
°
C
≤
T
A
≤
+125
°
C unless otherwise specified
2704ADA
Parameter
Input Offset
Voltage
Input Offset
Current
Input Bias
Current
Power Supply
Rejection Ratio
Common Mode
Rejection Ratio
Large Signal
Voltage Gain
Output Voltage
Range
V
O
low
V
O
high
-4.9
4.9
-4.8
4.8
-4.9
4.9
-4.8
4.8
-4.9
4.9
-4.8
V
R
L
= 10KΩ
I
OS
8.0
8.0
8.0
nA
Symbol
V
OS
Min
Typ
Max
2.0
Min
2704BDA
Typ
Max
4.0
Min
2704DA
Typ
Max
7.0
Unit
mV
Test Conditions
R
S
≤
100KΩ
I
B
10.0
10.0
10.0
nA
PSRR
60
75
60
75
60
75
dB
R
S
≤
100KΩ
CMRR
60
83
60
83
60
83
dB
R
S
≤
100KΩ
AV
10
25
10
25
10
25
V/mV
R
L
= 10KΩ
4.8
ALD2704A/ALD2704B
ALD2704
Advanced Linear Devices
3 of 9
Design & Operating Notes:
1. The ALD2704A/ALD2704B/ALD2704 CMOS operational amplifier
uses a 3 gain stage architecture and an improved frequency compen-
sation scheme to achieve large voltage gain, high output driving
capability, and better frequency stability. The ALD2704A/ALD2704B/
ALD2704 is internally compensated for unity gain stability using a
novel scheme. This design produces a clean single pole roll off in the
gain characteristics while providing for more than 70 degrees of phase
margin at the unity gain frequency. A unity gain buffer using the
ALD2704A/ALD2704B/ALD2704 will typically drive 400pF of external
load capacitance without stability problems. In the inverting unity gain
configuration, it can drive up to 800pF of load capacitance. Compared
to other CMOS operational amplifiers, the ALD2704A/ALD2704B/
ALD2704 is much more resistant to parasitic oscillations.
2. The ALD2704A/ALD2704B/ALD2704 has complementary p-channel
and n-channel input differential stages connected in parallel to accom-
plish rail to rail input common mode voltage range. With the common
mode input voltage close to the power supplies, one of the two
differential stages is switched off internally. To maintain compatibility
with other operational amplifiers, this switching point has been se-
lected to be about 1.5V above the negative supply voltage. As offset
voltage trimming on the ALD2704A/ALD2704B/ALD2704 is made
when the input voltage is symmetrical to the supply voltages, this
internal switching does not affect a large variety of applications such
as an inverting amplifier or non-inverting amplifier with a gain greater
than 2 (10V operation), where the common mode voltage does not
make excursions below this switching point.
3. The input bias and offset currents are essentially input protection diode
reverse bias leakage currents, and are typically less than 1pA at room
temperature. This low input bias current assures that the analog signal
from the source will not be distorted by input bias currents. For
applications where source impedance is very high, it may be necessary
to limit noise and hum pickup through proper shielding.
4. The output stage consists of class AB complementary output drivers,
capable of driving a low resistance load. The output voltage swing is
limited by the drain to source on-resistance of the output transistors as
determined by the bias circuitry, and the value of the load resistor. The
voltage follower configuration, the oscillation and resistant with the rail-
to-rail input and output feature, makes the ALD2704A/ALD2704B/
ALD2704 an effective analog signal buffer for medium to high source
impedance sensors, transducers, and other circuit networks.
5. The ALD2704A/ALD2704B/ALD2704 operational amplifier has been
designed to provide static discharge protection. Internally, the design
has been carefully implemented to minimize latch up. However, care
must be exercised when handling the device to avoid strong static
fields. In using the operational amplifier, the user is advised to power
up the circuit before, or simultaneously with, any input voltages applied
and to limit input voltages to not exceed 0.3V of the power supply
voltage levels. Alternatively, a 100KΩ or higher value resistor at the
input terminals will limit input currents to acceptable levels while
causing very small or negligible accuracy effects.
TYPICAL PERFORMANCE CHARACTERISTICS
COMMON MODE INPUT VOLTAGE RANGE
AS A FUNCTION OF SUPPLY VOLTAGE
±7
COMMON MODE INPUT
VOLTAGE RANGE (V)
OPEN LOOP VOLTAGE
GAIN (V/mV)
OPEN LOOP VOLTAGE GAIN AS A FUNCTION
OF SUPPLY VOLTAGE AND TEMPERATURE
1000
T
A
= 25°C
±6
±5
±4
±3
±2
±2
±3
±4
±5
±6
±7
SUPPLY VOLTAGE (V)
}
-55°C
}
+25°C
100
}
+125°C
10
R
L
= 10KΩ
R
L
= 5KΩ
1
0
±2
±4
SUPPLY VOLTAGE (V)
±6
±8
INPUT BIAS CURRENT AS A FUNCTION
OF AMBIENT TEMPERATURE
10000
SUPPLY CURRENT AS A FUNCTION
OF SUPPLY VOLTAGE
8
7
6
5
4
3
2
1
T
A
= -55°C
-25°C
+25°C
+80°C
+125°C
INPUTS GROUNDED
OUTPUT UNLOADED
INPUT BIAS CURRENT (pA)
1000
100
V
S
=
±5.0V
10
1.0
0.1
-50
-25
0
25
50
75
100
125
SUPPLY CURRENT (mA)
0
0
±1
±2
±3
±4
±5
±6
±7
AMBIENT TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
ALD2704A/ALD2704B
ALD2704
Advanced Linear Devices
4 of 9
TYPICAL PERFORMANCE CHARACTERISTICS (cont'd)
OUTPUT VOLTAGE SWING AS A
FUNCTION OF SUPPLY VOLTAGE
±7
OPEN LOOP VOLTAGE AS A FUNCTION
OF FREQUENCY
120
100
OPEN LOOP VOLTAGE
GAIN (dB)
OUTPUT VOLTAGE SWING (V)
±6
±5
±4
±3
±2
0
-55°C
≤
T
A
≤
125°C
RL = 10KΩ
PHASE SHIFT IN DEGREES
80
60
40
20
0
-20
1
10
100
1K
10K
V
S
=
±5.0V
T
A
= 25°C
0
45
90
135
180
100K
1M
10M
R
L
= 10KΩ
R
L
= 2KΩ
±1
±2
±3
±4
±5
±6
±7
SUPPLY VOLTAGE (V)
FREQUENCY (Hz)
INPUT OFFSET VOLTAGE AS A FUNCTION
OF AMBIENT TEMPERATURE
REPRESENTATIVE UNITS
INPUT OFFSET VOLTAGE (mV)
V
S
=
±5.0V
INPUT OFFSET VOLTAGE AS A FUNCTION
OF COMMON MODE INPUT VOLTAGE
15
INPUT OFFSET VOLTAGE (mV)
+5
+4
+3
+2
+1
0
-1
-2
-3
-4
-5
-50
-25
0
+25
+50
10
5
0
-5
-10
-15
V
S
=
±5.0V
T
A
= 25ºC
+75
+100 +125
-4
-2
0
+2
+4
+6
AMBIENT TEMPERATURE (°C)
COMMON MODE INPUT VOLTAGE (V)
OPEN LOOP VOLTAGE GAIN AS A
FUNCTION OF LOAD RESISTANCE
1000
VOLTAGE NOISE DENSITY AS A
FUNCTION OF FREQUENCY
150
VOLTAGE NOISE DENSITY
(nV/
√
Hz)
OPEN LOOP VOLTAGE
GAIN (V/mV)
125
100
75
50
25
0
V
S
=
±5.0V
T
A
= 25°C
100
10
V
S
=
±5.0V
T
A
= 25°C
1
1K
10K
100K
1000K
10
100
1K
10K
100K
1000K
LOAD RESISTANCE (Ω)
FREQUENCY (Hz)
LARGE - SIGNAL TRANSIENT
RESPONSE
5V/div
V
S
=
±5.0V
T
A
= 25°C
R
L
= 1KΩ
C
L
= 50pF
SMALL - SIGNAL TRANSIENT
RESPONSE
100mV/div
V
S
=
±
5.0V
T
A
= 25°C
R
L
= 1.0KΩ
C
L
= 50pF
5V/div
2µs/div
50mV/div
1µs/div
ALD2704A/ALD2704B
ALD2704
Advanced Linear Devices
5 of 9
