DUAL MICROPOWER PRECISION RAIL-TO-RAIL CMOS OPERATIONAL AMPLIFIER
ALD2711A/ALD2711B
ALD2711
ADVANCED
LINEAR
DEVICES, INC.
GENERAL DESCRIPTION
The ALD2711 is a dual monolithic CMOS micropower precision high
slew rate operational amplifier intended for a broad range of analog
applications using ±1V to ±6V dual power supply systems, as well as
+2V to +12V battery operated systems. All device characteristics are
specified for +5V single supply or ±2.5V dual supply systems. Typical
supply current is 200µA at 5V supply voltage. It is manufactured with
Advanced Linear Devices' enhanced ACMOS silicon gate CMOS
process.
The device has an input stage that operates to +300mV above and
-300mV below the supply voltages with no adverse effects and/or
phase reversals.
The ALD2711 has been developed specifically for the +5V single
supply or ±1V to ±6V dual supply user. Several important characteristics
of the device make application easier to implement at those voltages.
First, each operational amplifier can operate with rail to rail input and
output voltages. This means the signal input voltage and output
voltage can be at the positive and negative supply voltages. This
feature allows numerous analog serial stages and flexibility in input
signal bias levels. Secondly, each device was designed to accommodate
mixed applications where digital and analog circuits may operate off
the same power supply or battery. Thirdly, the output stage can
typically drive up to 50pF capacitive and 10K Ω resistive loads.
These features, combined with extremely low input currents, high open
loop voltage gain, high useful bandwidth, and slew rate make the
ALD2711 a versatile, micropower operational amplifier.
The ALD2711 with on-chip offset voltage trimming allows the device to
be used without nulling in most applications. The unique characteristics
of the ALD2711 are modeled in an available macromodel.
FEATURES
• Designed and characterized for 5V operation
• Linear mode operation with input voltages
300mV beyond supply rails
• Output voltages to within 2mV of power supply
rails when driving a high impedance load
• Unity gain stable
• Extremely low input bias currents -- 0.01pA
• Dual power supply ±1.0V to ±6.0V
• Single power supply +2V to +12V
• High voltage gain
• Output short circuit protected
• Unity gain bandwidth of 0.7MHz
• Slew rate of 0.7V/µs
• Low power dissipation
• Symmetrical complementary output drive
APPLICATIONS
• Voltage follower/buffer/amplifier
• Charge integrator
• Photodiode amplifier
• Data acquisition systems
• High performance portable
instruments
• Signal conditioning circuits
• Sensor and transducer amplifiers
• Low leakage amplifiers
• Active filters
• Sample/Hold amplifier
• Picoammeter
• Current to voltage converter
PIN CONFIGURATION
1
2
3
4
8
7
6
5
TOP VIEW
DA, PA, SA PACKAGE
OUT
A
-IN
A
+IN
A
V+
-IN
B
+IN
B
V-
OUT
B
ORDERING INFORMATION
Operating Temperature Range
-55°C to +125°C0°C to +70°C0°C to +70°C
8-Pin 8-Pin 8-Pin
CERDIP Small Outline Plastic Dip
Package Package (SOIC) Package
ALD 2711A DA ALD 2711A SA ALD 2711A PA
ALD 2711B DA ALD 2711B SA ALD 2711B PA
ALD 2711 DA ALD 2711 SA ALD 2711 PA
* Contact factory for industrial temperature range.
© 1998 Advanced Linear Devices, Inc. 415 T asman Drive, Sunnyvale, California 94089 -1706 Tel: (408) 747-1 155 Fax: (408) 747-1286 http://www .aldinc.com
ALD2711A/ALD2711B Advanced Linear Devices 2
ALD2711
Supply VS±1.0 ±6.3 ±1.0 ±6.3 ±1.0 ±6.0 V Dual Supply
Voltage V+2.0 12.6 2.0 12.6 2.0 12.6 V Single Supply
Input Offset VOS 0.25 0.6 0.5 1.0 0.8 1.5 mV RS ≤ 100KΩ
Voltage 1.0 1.5 2.0 mV 0°C ≤ TA ≤ +70°C
Input Offset IOS 0.01 10 0.01 10 0.01 10 pA TA = 25°C
Current 280 280 280 pA 0°C ≤ TA ≤ +70°C
Input Bias IB0.01 10 0.01 10 0.01 10 pA TA = 25°C
Current 280 280 280 pA 0°C ≤ TA ≤ +70°C
Input Voltage VIR -0.3 5.3 -0.3 5.3 -0.3 5.3 V V+ = +5V
Range -2.8 2.8 -2.8 2.8 -2.8 2.8 V VS = ±2.5V
Input RIN 1013 1013 1013 Ω
Resistance
Input Offset TCVOS 557µV/°CR
S ≤ 100KΩ
Voltage Drift
Power Supply PSRR 63 90 63 90 60 90 dB RS ≤ 100KΩ
Rejection Ratio 63 90 63 90 60 90 dB 0°C ≤ TA ≤ +70°C
Common Mode CMRR 63 90 63 90 60 90 dB RS ≤ 100KΩ
Rejection Ratio 63 90 63 90 60 90 dB 0°C ≤ TA ≤ +70°C
Large Signal AV15 100 15 100 10 100 V/mV RL = 100KΩ
Voltage Gain 300 300 300 V/mV RL ≥ 1MΩ
10 10 7 V/mV RL = 100KΩ
0°C ≤ TA ≤ +70°C
Output VO low 0.001 0.01 0.001 0.01 0.001 0.01 V RL = 1MΩ V+= +5V
Voltage VO high 4.99 4.999 4.99 4.999 4.99 4.999 V 0°C ≤ TA ≤ +70°C
Range VO low -2.48 -2.40 -2.48 -2.40 -2.48 -2.40 V RL = 100KΩ
VO high 2.40 2.48 2.40 2.48 2.40 2.48 V 0°C ≤ TA ≤ +70°C
Output Short ISC 111mA
Circuit Current
Supply IS200 450 200 450 200 450 µAV
IN = 0V
Current No Load
Power PD1.0 2.25 1.0 2.25 1.0 2.25 VS = ±2.5V Both
Dissipation 0.25 0.6 0.25 0.6 0.25 0.6 mW VS = ±1.0V amplifiers
OPERATING ELECTRICAL CHARACTERISTICS
TA = 25°C VS = ±2.5V unless otherwise specified
2711A 2711B 2711
Parameter Symbol Min Typ Max Min Typ Max Min Typ Max Unit Test Conditions
ABSOLUTE MAXIMUM RATINGS
Supply voltage, V+ 13.2V
Differential input voltage range -0.3V to V+ +0.3V
Power dissipation 600 mW
Operating temperature range PA,SA package 0°C to +70°C
DA package -55°C to +125°C
Storage temperature range -65°C to +150°C
Lead temperature, 10 seconds +260°C
ALD2711A/ALD2711B Advanced Linear Devices 3
ALD2711
VS = ±2.5V -55°C ≤ TA ≤ +125°C unless otherwise specified
2711A DA 2711B DA 2711 DA
Parameter Symbol Min Typ Max Min Typ Max Min Typ Max Unit Test Conditions
Power Supply PSRR 100 100 100 dB RS ≤ 100KΩ
Rejection Ratio
Common Mode CMRR 100 100 100 dB RS ≤ 100KΩ
Rejection Ratio
Large Signal AV300 300 300 V/mV RL = 100KΩ
Voltage Gain
Output Voltage VO low -4.98 -4.90 -4.98 -4.90 -4.98 -4.90 V RL = 100KΩ
Range VO high 4.90 4.98 4.90 4.98 4.90 4.98 V
Bandwidth BW1.0 1.0 1.0 MHz
Slew Rate SR1.0 1.0 1.0 V/µsA
V = +1
CL = 50pF
Input
Capacitance CIN 111pF
Bandwidth BW700 700 700 KHz
Slew Rate SR0.7 0.7 0.7 V/µsA
V = +1
RL = 100KΩ
Rise time tr0.2 0.2 0.2 µsR
L = 100KΩ
Overshoot 20 20 20 % RL = 100KΩ
Factor CL = 50pF
Settling ts10.0 10.0 10.0 µs 0.1% AV = 100
Time RL = 100KΩ
CL = 50pF
Channel CS140 140 140 dB AV = 100
Separation
OPERATING ELECTRICAL CHARACTERISTICS (cont'd)
TA = 25°C VS = ±2.5V unless otherwise specified
2711A 2711B 2711
Parameter Symbol Min Typ Max Min Typ Max Min Typ Max Unit Test Conditions
TA = 25°C VS = ±5.0V unless otherwise specified
2711A 2711B 2711
Parameter Symbol Min Typ Max Min Typ Max Min Typ Max Unit Test Conditions
Input Offset VOS 1.5 2.0 2.5 mV RS ≤ 100KΩ
Voltage
Input Offset IOS 44 4nA
Current
Input Bias IB44 4nA
Current
Power Supply PSRR 60 85 60 85 60 85 dB RS ≤ 100KΩ
Rejection Ratio
Common Mode CMRR 60 83 60 83 60 83 dB RS ≤ 100KΩ
Rejection Ratio
Large Signal AV 10 50 10 50 10 50 V/mV RL ≤ 100KΩ
Voltage Gain
Output Voltage VO low -2.47 -2.40 -2.47 -2.40 -2.47 -2.40 V
Range VO high 2.35 2.45 2.35 2.45 2.35 2.45 V RL ≤ 100KΩ
ALD2711A/ALD2711B Advanced Linear Devices 4
ALD2711
Design & Operating Notes:
1. The ALD2711 CMOS operational amplifier uses a 3 gain stage
architecture and an improved frequency compensation scheme to
achieve large voltage gain, high output driving capability, and better
frequency stability. In a conventional CMOS operational amplifier
design, compensation is achieved with a pole splitting capacitor
together with a nulling resistor. This method is, however, very bias
dependent and thus cannot accommodate the large range of supply
voltage operation as is required from a stand alone CMOS operational
amplifier. The ALD2711 is internally compensated for unity gain
stability using a novel scheme that does not use a nulling resistor. This
scheme 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.
2. The ALD2711 has complementary p-channel and n-channel input
differential stages connected in parallel to accomplish rail to rail input
common mode voltage range. This means that with the ranges of
common mode input voltage close to the power supplies, one of the
two differential stages is switched off internally. To maintain com-
patibility with other operational amplifiers, this switching point has
been selected to be about 1.5V below the positive supply voltage.
Since offset voltage trimming on the ALD2711 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 larger than 2.5 (5V
operation), where the common mode voltage does not make excur-
sions above this switching point. The user should however, be aware
that this switching does take place if the operational amplifier is
connected as a unity gain buffer and should make provision in his
design to allow for input offset voltage variations.
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. Normally,
this extremely high input impedance of greater than 1012Ω would not
be a problem as the source impedance would limit the node impedance.
However, 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.
When connected in the voltage follower configuration, the oscillation
resistant feature, combined with the rail to rail input and output feature,
makes an effective analog signal buffer for medium to high source
impedance sensors, transducers, and other circuit networks.
5. The ALD2711 operational amplifier has been designed to provide full
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 that may degrade
a diode junction, causing increased input leakage currents. 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.
6. The ALD2711, with its micropower operation, offers numerous benefits
in reduced power supply requirements, less noise coupling and
current spikes, less thermally induced drift, better overall reliability due
to lower self heating, and lower input bias current. It requires
practically no warm up time as the chip junction heats up to only 0.2°C
above ambient temperature under most operating conditions.
TYPICAL PERFORMANCE CHARACTERISTICS
SUPPLY CURRENT AS A FUNCTION
OF SUPPLY VOLTAGE
SUPPLY VOLTAGE (V)
500
300
400
0
200
SUPPLY CURRENT (µA)
0±1±2±3±4±5±6
T
A
= -55°C
-25°C+25°C
+70°C
+125°C
INPUTS GROUNDED
OUTPUT UNLOADED
COMMON MODE INPUT VOLTAGE RANGE
AS A FUNCTION OF SUPPLY VOLTAGE
SUPPLY VOLTAGE (V)
COMMON MODE INPUT
VOLTAGE RANGE (V)
±7
±6
±5
±4
±3
±2
±1
00 ±1 ±2 ±3 ±4 ±5 ±6 ±7
TA = 25°C
OPEN LOOP VOLTAGE GAIN AS A
FUNCTION OF LOAD RESISTANCE
10M
LOAD RESISTANCE (Ω)
10K 100K 1M
1000
100
10
1
OPEN LOOP VOLTAGE
GAIN (V/mV)
V
S
= ±2.5V
T
A
= 25°C
INPUT BIAS CURRENT AS A FUNCTION
OF AMBIENT TEMPERATURE
AMBIENT TEMPERATURE (°C)
100
10
1.0
0.01
0.1
INPUT BIAS CURRENT (pA)
100-25 0 75 1255025-50
1000
V
S
= ±2.5V
ALD2711A/ALD2711B Advanced Linear Devices 5
ALD2711
OUTPUT VOLTAGE SWING AS A FUNCTION
OF SUPPLY VOLTAGE
SUPPLY VOLTAGE (V)
0±1±2±3±4±7±6±5
±6
±5
±4
±3
±2
±1
OUTPUT VOLTAGE SWING (V)
+25°C ≤ T
A
≤ +125°C
R
L
= 100KΩ
TYPICAL PERFORMANCE CHARACTERISTICS
INPUT OFFSET VOLTAGE AS A FUNCTION
OF AMBIENT TEMPERATURE
REPRESENTATIVE UNITS
AMBIENT TEMPERATURE (°C)
INPUT OFFSET VOLTAGE (mV)
-50 -25 0 +25 +50 +75 +100 +125
+4
+5
+3
+1
+2
0
-2
-1
-4
-3
-5
V
S
= ±2.5V
OPEN LOOP VOLTAGE AS A FUNCTION
OF FREQUENCY
FREQUENCY (Hz)
1 10 100 1K 10K 1M 10M100K
120
100
80
60
40
20
0
-20
OPEN LOOP VOLTAGE
GAIN (dB)
90
0
45
180
135
PHASE SHIFT IN DEGREES
V
S
= ±2.5V
T
A
= 25°C
INPUT OFFSET VOLTAGE AS A FUNCTION
OF COMMON MODE INPUT VOLTAGE
COMMON MODE INPUT VOLTAGE (V)
-2 -1 0 +1 +3+2
15
10
5
-5
-10
0
-15
INPUT OFFSET VOLTAGE (mV)
V
S
= ±2.5V
T
A
= 25°C
LARGE - SIGNAL TRANSIENT
RESPONSE
2V/div
500mV/div 5µs/div
V
S
= ±1.0V
T
A
= 25°C
R
L
= 100KΩ
C
L
= 50pF
LARGE - SIGNAL TRANSIENT
RESPONSE
5V/div
2V/div 5µs/div
V
S
= ±2.5V
T
A
= 25°C
R
L
= 100KΩ
C
L
= 50pF
SMALL - SIGNAL TRANSIENT
RESPONSE
100mV/div
20mV/div 2µs/div
V
S
= ±2.5V
T
A
= 25°C
R
L
= 100KΩ
C
L
= 50pF
OPEN LOOP VOLTAGE GAIN AS A FUNCTION
OF SUPPLY VOLTAGE AND TEMPERATURE
SUPPLY VOLTAGE (V)
1000
100
10
1
OPEN LOOP VOLTAGE
GAIN (V/mV)
0 ±2 ±4 ±6
-55°C ≤ T
A
≤ +125°C
R
L
= 100KΩ
±8
ALD2711A/ALD2711B Advanced Linear Devices 6
ALD2711
TYPICAL APPLICATIONS
PHOTO DETECTOR CURRENT TO
VOLTAGE CONVERTER
LOW VOLTAGE INSTRUMENTATION AMPLIFIER
WIEN BRIDGE OSCILLATOR (RAIL-TO-RAIL)
SINE WAVE GENERATOR
RAIL-TO-RAIL VOLTAGE FOLLOWER/BUFFER RAIL-TO-RAIL WAVEFORM
Performance waveforms.
Upper trace is the output of a
Wien Bridge Oscillator. Lower
trace is the output of Rail-to-Rail
voltage follower.
0V
+5V
OUTPUT
0V
+5V
INPUT
V- = - 2.5V
10M
10M
10M
10M
10M
10M
R
IN
= 10MΩ Accuracy limited by resistor tolerances and input offset voltage
V+ = +2.5V
-
+
0.1µF
0.1µFV
OUT
V- ≤ V
IN
≤ V+
V- ≤ V
OUT
≤ V+
V
1
V
4
V
3
V
2
V
OUT
= V
1
+ V
2
- V
3
- V
4
1/2 ALD2711
HIGH INPUT IMPEDANCE RAIL-TO-RAIL PRECISION
DC SUMMING AMPLIFIER RAIL-TO-RAIL WINDOW COMPARATOR
10K
10K
10K
+2.5V
-2.5V
.01µF
C = .01µFR = 10K
-
+
1/2 ALD2711
f = 1 = 1.6KHZ
2πRC
~~
V
OUT
* See Rail-to-Rail Waveform
+5V
+
-
+
-
V
IN
100K
V
REF
(HIGH)
V
REF
(LOW)
3
2
5
6
8
4
1
7
1/4 74 C00
1/2 ALD2711
V
OUT
V
OUT (LOW)
FOR V
REF (LOW)
<
V
IN
< V
REF(HIGH)
100K
1/2 ALD2711
-
+
OUTPUT
5V
0.1µF
* See Rail-to-Rail Waveform
0≤ V
IN
≤ 5V
V
IN
Z
IN
= 10
13
Ω
~
1/2 ALD2711
+
-
+2.5V
-2.5V
RF = 5M
I
PHOTODIODE
VOUT = I X RF
RL = 100K
1/2 ALD2711
50K
100K
100K
f max = 20KHz
-40mV ≤ V
IN
≤ 40mV
-
+
0.1µF
0.1µF
V+
V-
0.1µF
0.1µF
V+
V-
-
+
100K
100K
-
500K
0.1µF
V+
V+ 1M
+
1M V-
V- 0.1µF
V
OUT
1M
1/2 ALD2711
1/2 ALD2711
GAIN = 25 V- ≤ V
OUT
≤ V+ All resistors are 1%
V+ = +1.0V V- = -1.0V Short Circuit Input Current 1µA
1M
1/2 ALD2711
