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LM124-N
,
LM224-N
LM2902-N
,
LM324-N
SNOSC16D MARCH 2000REVISED JANUARY 2015
LMx24-N, LM2902-N Low-Power, Quad-Operational Amplifiers
1 Features 3 Description
The LM124-N series consists of four independent,
1 Internally Frequency Compensated for Unity Gain high-gain, internally frequency compensated
Large DC Voltage Gain 100 dB operational amplifiers designed to operate from a
Wide Bandwidth (Unity Gain) 1 MHz single power supply over a wide range of voltages.
(Temperature Compensated) Operation from split-power supplies is also possible
and the low-power supply current drain is
Wide Power Supply Range: independent of the magnitude of the power supply
Single Supply 3 V to 32 V voltage.
or Dual Supplies ±1.5 V to ±16 V Application areas include transducer amplifiers, DC
Very Low Supply Current Drain (700 μA) gain blocks and all the conventional op amp circuits
—Essentially Independent of Supply Voltage which now can be more easily implemented in single
Low Input Biasing Current 45 nA power supply systems. For example, the LM124-N
series can directly operate off of the standard 5-V
(Temperature Compensated) power supply voltage which is used in digital systems
Low Input Offset Voltage 2 mV and easily provides the required interface electronics
and Offset Current: 5 nA without requiring the additional ±15 V power supplies.
Input Common-Mode Voltage Range Includes
Ground Device Information(1)
Differential Input Voltage Range Equal to the PART NUMBER PACKAGE BODY SIZE (NOM)
Power Supply Voltage LM124-N CDIP (14) 19.56 mm × 6.67 mm
Large Output Voltage Swing 0 V to V+1.5 V LM224-N CDIP (14) 19.56 mm × 6.67 mm
Advantages: PDIP (14) 19.177 mm × 6.35 mm
Eliminates Need for Dual Supplies LM324-N SOIC (14) 8.65 mm × 3.91 mm
Four Internally Compensated Op Amps in a TSSOP (14) 5.00 mm × 4.40 mm
Single Package PDIP (14) 19.177 mm × 6.35 mm
Allows Direct Sensing Near GND and VOUT LM2902-N SOIC (14) 8.65 mm × 3.91 mm
also Goes to GND TSSOP (14) 5.00 mm × 4.40 mm
Compatible With All Forms of Logic (1) For all available packages, see the orderable addendum at
Power Drain Suitable for Battery Operation the end of the datasheet.
In the Linear Mode the Input Common-Mode,
Voltage Range Includes Ground and the Schematic Diagram
Output Voltage
Can Swing to Ground, Even Though Operated
from Only a Single Power Supply Voltage
Unity Gain Cross Frequency is Temperature
Compensated
Input Bias Current is Also Temperature
Compensated
2 Applications
Transducer Amplifiers
DC Gain Blocks
Conventional Op Amp Circuits
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM124-N
,
LM224-N
LM2902-N
,
LM324-N
SNOSC16D MARCH 2000REVISED JANUARY 2015
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Table of Contents
7.3 Feature Description................................................. 11
1 Features.................................................................. 17.4 Device Functional Modes........................................ 11
2 Applications ........................................................... 18 Application and Implementation ........................ 13
3 Description............................................................. 18.1 Application Information............................................ 13
4 Revision History..................................................... 28.2 Typical Applications ............................................... 13
5 Pin Configuration and Functions......................... 39 Power Supply Recommendations...................... 23
6 Specifications......................................................... 410 Layout................................................................... 23
6.1 Absolute Maximum Ratings ...................................... 410.1 Layout Guidelines ................................................. 23
6.2 ESD Ratings.............................................................. 410.2 Layout Example .................................................... 23
6.3 Recommended Operating Conditions....................... 411 Device and Documentation Support................. 24
6.4 Thermal Information.................................................. 511.1 Related Links ........................................................ 24
6.5 Electrical Characteristics: LM124A/224A/324A ........ 511.2 Trademarks........................................................... 24
6.6 Electrical Characteristics: LM124-N/224-N/324-
N/2902-N ................................................................... 611.3 Electrostatic Discharge Caution............................ 24
6.7 Typical Characteristics.............................................. 811.4 Glossary................................................................ 24
7 Detailed Description............................................ 11 12 Mechanical, Packaging, and Orderable
Information........................................................... 24
7.1 Overview................................................................. 11
7.2 Functional Block Diagram....................................... 11
4 Revision History
Changes from Revision C (November 2012) to Revision D Page
Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional
Modes,Application and Implementation section, Power Supply Recommendations section, Layout section, Device
and Documentation Support section, and Mechanical, Packaging, and Orderable Information section ............................... 1
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5 Pin Configuration and Functions
J Package
14-Pin CDIP
Top View
D Package
14-Pin SOIC
Top View
Pin Functions
PIN TYPE DESCRIPTION
NAME NO.
OUTPUT1 1 O Output, Channel 1
INPUT1- 2 I Inverting Input, Channel 1
INPUT1+ 3 I Noninverting Input, Channel 1
V+ 4 P Positive Supply Voltage
INPUT2+ 5 I Nonnverting Input, Channel 2
INPUT2- 6 I Inverting Input, Channel 2
OUTPUT2 7 O Output, Channel 2
OUTPUT3 8 O Output, Channel 3
INPUT3- 9 I Inverting Input, Channel 3
INPUT3+ 10 I Noninverting Input, Channel 3
GND 11 P Ground or Negative Supply Voltage
INPUT4+ 12 I Noninverting Input, Channel 4
INPUT4- 13 I Inverting Input, Channel 4
OUTPUT4 14 O Output, Channel 4
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6 Specifications
6.1 Absolute Maximum Ratings
See (1)(2).LM124-N/LM224-N/LM324-N LM2902-N
LM124A/LM224A/LM324A
MIN MAX MIN MAX UNIT
Supply Voltage, V+32 26 V
Differential Input Voltage 32 26 V
Input Voltage 0.3 32 0.3 26 V
Input Current (VIN <0.3 V)(3) 50 50 mA
Power PDIP 1130 1130 mW
Dissipation(4) CDIP 1260 1260 mW
SOIC Package 800 800 mW
Output Short-Circuit to GND V+15 V and TA= 25°C Continuous Continuous
(One Amplifier)(5)
Lead Temperature (Soldering, 10 seconds) 260 260 °C
Dual-In-Line Soldering (10 seconds) 260 260 °C
Package
Soldering
Information Small Vapor Phase (60 seconds) 215 215 °C
Outline Infrared (15 seconds) 220 220 °C
Package
Storage temperature, Tstg –65 150 –65 150 °C
(1) Refer to RETS124AX for LM124A military specifications and refer to RETS124X for LM124-N military specifications.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) This input current will only exist when the voltage at any of the input leads is driven negative. It is due to the collector-base junction of
the input PNP transistors becoming forward biased and thereby acting as input diode clamps. In addition to this diode action, there is
also lateral NPN parasitic transistor action on the IC chip. This transistor action can cause the output voltages of the op amps to go to
the V+voltage level (or to ground for a large overdrive) for the time duration that an input is driven negative. This is not destructive and
normal output states will re-establish when the input voltage, which was negative, again returns to a value greater than 0.3 V (at 25°C).
(4) For operating at high temperatures, the LM324-N/LM324A/LM2902-N must be derated based on a 125°C maximum junction
temperature and a thermal resistance of 88°C/W which applies for the device soldered in a printed circuit board, operating in a still air
ambient. The LM224-N/LM224A and LM124-N/LM124A can be derated based on a 150°C maximum junction temperature. The
dissipation is the total of all four amplifiers—use external resistors, where possible, to allow the amplifier to saturate of to reduce the
power which is dissipated in the integrated circuit.
(5) Short circuits from the output to V+can cause excessive heating and eventual destruction. When considering short circuits to ground,
the maximum output current is approximately 40 mA independent of the magnitude of V+. At values of supply voltage in excess of 15 V,
continuous short-circuits can exceed the power dissipation ratings and cause eventual destruction. Destructive dissipation can result
from simultaneous shorts on all amplifiers.
6.2 ESD Ratings VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±250 V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted) MIN MAX UNIT
Supply Voltage (V+- V-): LM124-N/LM124A/LM224-N/LM224A/LM324-N/LM324A 3 32 V
Supply Voltage (V+- V-): LM2902-N 3 26 V
Operating Input Voltage on Input pins 0 V+ V
Operating junction temperature, TJ: LM124-N/LM124A -55 125 °C
Operating junction temperature, TJ: L2902-N -40 85 °C
Operating junction temperature, TJ: LM224-N/LM224A -25 85 °C
Operating junction temperature, TJ: LM324-N/LM324A 0 70 °C
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6.4 Thermal Information LM124-N / LM324-N /
LM224-N LM2902-N
THERMAL METRIC(1) UNIT
J/CDIP D/SOIC
14 PINS 14 PINS
RθJA Junction-to-ambient thermal resistance 88 88 °C/W
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
6.5 Electrical Characteristics: LM124A/224A/324A
V+= 5.0 V, (1), unless otherwise stated LM124A LM224A LM324A
PARAMETER TEST CONDITIONS UNIT
MIN TYP MAX MIN TYP MAX MIN TYP MAX
Input Offset Voltage TA= 25°C(2) 1 2 1 3 2 3 mV
IIN(+) or IIN(), VCM = 0 V,
Input Bias Current(3) 20 50 40 80 45 100 nA
TA= 25°C
IIN(+) or IIN(), VCM = 0 V,
Input Offset Current 2 10 2 15 5 30 nA
TA= 25°C
V+= 30 V, (LM2902-N,
Input Common-Mode 0 0 0 V
V+1.5 V+1.5 V+1.5
Voltage Range(4) V+= 26 V), TA= 25°C
Over Full Temperature Range,
RL=On All Op Amps 1.5 3 1.5 3 1.5 3
Supply Current mA
V+= 30 V (LM2902-N V+= 26 V)
0.7 1.2 0.7 1.2 0.7 1.2
V+= 5 V
Large Signal V+= 15 V, RL2 k,50 100 50 100 25 100 V/mV
Voltage Gain (VO= 1 V to 11 V), TA= 25°C
Common-Mode DC, VCM = 0 V to V+1.5 V, 70 85 70 85 65 85 dB
Rejection Ratio TA= 25°C
V+= 5 V to 30 V, (LM2902-N,
Power Supply 65 100 65 100 65 100 dB
V+= 5V to 26 V),
Rejection Ratio TA= 25°C
Amplifier-to-Amplifier f = 1 kHz to 20 kHz, TA= 25°C, 120 120 120 dB
Coupling(5) (Input Referred)
VIN+= 1 V, VIN= 0 V,
Source 20 40 20 40 20 40 mA
V+= 15 V, VO= 2 V, TA= 25°C
VIN= 1 V, VIN+= 0 V,
Output 10 20 10 20 10 20
Current V+= 15 V, VO= 2 V, TA= 25°C
Sink μA
VIN= 1 V, VIN+= 0 V, 12 50 12 50 12 50
V+= 15 V, VO= 200 mV, TA= 25°C
V+= 15 V,
Short Circuit to Ground 40 60 40 60 40 60 mA
TA= 25°C(6)
Input Offset Voltage See(2) 4 4 5 mV
VOS Drift RS= 0 Ω7 20 7 20 7 30 μV/°C
Input Offset Current IIN(+) IIN(), VCM = 0 V 30 30 75 nA
(1) These specifications are limited to 55°C TA+125°C for the LM124-N/LM124A. With the LM224-N/LM224A, all temperature
specifications are limited to 25°C TA+85°C, the LM324-N/LM324A temperature specifications are limited to 0°C TA+70°C, and
the LM2902-N specifications are limited to 40°C TA+85°C.
(2) VO1.4V, RS= 0 Ωwith V+from 5 V to 30 V; and over the full input common-mode range (0 V to V+1.5 V) for LM2902-N, V+from 5
V to 26 V.
(3) The direction of the input current is out of the IC due to the PNP input stage. This current is essentially constant, independent of the
state of the output so no loading change exists on the input lines.
(4) The input common-mode voltage of either input signal voltage should not be allowed to go negative by more than 0.3 V (at 25°C). The
upper end of the common-mode voltage range is V+1.5 V (at 25°C), but either or both inputs can go to 32 V without damage (26 V for
LM2902-N), independent of the magnitude of V+.
(5) Due to proximity of external components, insure that coupling is not originating via stray capacitance between these external parts. This
typically can be detected as this type of capacitance increases at higher frequencies.
(6) Short circuits from the output to V+can cause excessive heating and eventual destruction. When considering short circuits to ground,
the maximum output current is approximately 40 mA independent of the magnitude of V+. At values of supply voltage in excess of 15 V,
continuous short-circuits can exceed the power dissipation ratings and cause eventual destruction. Destructive dissipation can result
from simultaneous shorts on all amplifiers.
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Electrical Characteristics: LM124A/224A/324A (continued)
V+= 5.0 V, (1), unless otherwise stated LM124A LM224A LM324A
PARAMETER TEST CONDITIONS UNIT
MIN TYP MAX MIN TYP MAX MIN TYP MAX
IOS Drift RS= 0 Ω10 200 10 200 10 300 pA/°C
Input Bias Current IIN(+) or IIN()40 100 40 100 40 200 nA
Input Common-Mode V+= 30 V, 0 0 0 V
V+2 V+2 V+2
Voltage Range(4) (LM2902-N, V+= 26 V)
Large Signal V+= 15 V (VOSwing = 1 V to 11 V), 25 25 15 V/mV
Voltage Gain RL2 kΩ
RL= 2 kΩ26 26 26
V+= 30 V
Output VOH (LM2902-N, V
RL= 10 kΩ27 28 27 28 27 28
Voltage V+= 26 V)
Swing 5 20 5 20 5 20 mV
VOL V+= 5 V, RL= 10 kΩ
VIN+= +1V,
Source 10 20 10 20 10 20
VIN= 0V,
V+= 15V
Output VO= 2 V mA
Current 10 15 5 8 5 8
VIN= +1V,
Sink VIN+= 0V,
V+= 15V
6.6 Electrical Characteristics: LM124-N/224-N/324-N/2902-N
V+= +5.0V, (1), unless otherwise stated LM124-N / LM224-N LM324-N LM2902-N
PARAMETER TEST CONDITIONS UNIT
MIN TYP MAX MIN TYP MAX MIN TYP MAX
Input Offset Voltage TA= 25°C(2) 2 5 2 7 2 7 mV
Input Bias Current(3) IIN(+) or IIN(), VCM = 0 V, TA= 25°C 45 150 45 250 45 250 nA
Input Offset Current IIN(+) or IIN(), VCM = 0 V, TA= 25°C 3 30 5 50 5 50 nA
Input Common-Mode Voltage V+= 30 V, (LM2902-N, V+= 26V), V+1. V+1. V+1.
0 0 0 V
Range(4) 5 5 5
TA= 25°C
Over Full Temperature Range
RL=On All Op Amps, 1.5 3 1.5 3 1.5 3
Supply Current mA
V+= 30 V (LM2902-N V+= 26 V)
0.7 1.2 0.7 1.2 0.7 1.2
V+= 5 V
V+= 15V, RL2 k,
Large Signal Voltage Gain 50 100 25 100 25 100 V/mV
(VO= 1 V to 11 V), TA= 25°C
Common-Mode Rejection 70 85 65 85 50 70 dB
DC, VCM = 0 V to V+1.5 V, TA= 25°C
Ratio
V+= 5 V to 30 V (LM2902-N,
Power Supply Rejection Ratio 65 100 65 100 50 100 dB
V+= 5 V to 26 V), TA= 25°C
Amplifier-to-Amplifier f = 1 kHz to 20 kHz, TA= 25°C 120 120 120 dB
Coupling(5) (Input Referred)
(1) These specifications are limited to 55°C TA+125°C for the LM124-N/LM124A. With the LM224-N/LM224A, all temperature
specifications are limited to 25°C TA+85°C, the LM324-N/LM324A temperature specifications are limited to 0°C TA+70°C, and
the LM2902-N specifications are limited to 40°C TA+85°C.
(2) VO1.4V, RS= 0 Ωwith V+from 5 V to 30 V; and over the full input common-mode range (0 V to V+1.5 V) for LM2902-N, V+from 5
V to 26 V.
(3) The direction of the input current is out of the IC due to the PNP input stage. This current is essentially constant, independent of the
state of the output so no loading change exists on the input lines.
(4) The input common-mode voltage of either input signal voltage should not be allowed to go negative by more than 0.3 V (at 25°C). The
upper end of the common-mode voltage range is V+1.5 V (at 25°C), but either or both inputs can go to 32 V without damage (26 V for
LM2902-N), independent of the magnitude of V+.
(5) Due to proximity of external components, insure that coupling is not originating via stray capacitance between these external parts. This
typically can be detected as this type of capacitance increases at higher frequencies.
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Electrical Characteristics: LM124-N/224-N/324-N/2902-N (continued)
V+= +5.0V, (1), unless otherwise stated LM124-N / LM224-N LM324-N LM2902-N
PARAMETER TEST CONDITIONS UNIT
MIN TYP MAX MIN TYP MAX MIN TYP MAX
VIN+= 1 V, VIN= 0 V,
Source 20 40 20 40 20 40 mA
V+= 15 V, VO= 2 V, TA= 25°C
Output VIN= 1 V, VIN+= 0 V, 10 20 10 20 10 20 mA
Current V+= 15 V, VO= 2 V, TA= 25°C
Sink VIN= 1 V, VIN+= 0 V, 12 50 12 50 12 50 µA
V+= 15 V, VO= 200 mV, TA= 25°C
Short Circuit to Ground 40 60 40 60 40 60 mA
V+= 15 V, TA= 25°C(6)
Input Offset Voltage See (2) 7 9 10 mV
VOS Drift RS= 0 Ω7 7 7 µV/°C
Input Offset Current IIN(+) IIN(), VCM = 0 V 100 150 45 200 nA
IOS Drift RS= 0 Ω10 10 10 pA/°C
Input Bias Current IIN(+) or IIN()40 300 40 500 40 500 nA
Input Common-Mode Voltage 0 0 0 V
V+= 30 V, (LM2902-N, V+= 26 V) V+2 V+2 V+2
Range(4)
V+= 15 V (VOSwing = 1V to 11V),
Large Signal Voltage Gain 25 15 15 V/mV
RL2 kΩ
RL= 2 kΩ26 26 22
V+= 30 V (LM2902-N,
Output VOH V
V+= 26 V) RL= 10 kΩ27 28 27 28 23 24
Voltage
Swing VOL 5 20 5 20 5 100 mV
V+= 5 V, RL= 10 kΩ
VIN+= 1 V,
Source VO= 2 V 10 20 10 20 10 20 mA
VIN= 0 V,
V+= 15 V
Output
Current VIN= 1 V,
Sink 5 8 5 8 5 8 mA
VIN+= 0 V,
V+= 15 V
(6) Short circuits from the output to V+can cause excessive heating and eventual destruction. When considering short circuits to ground,
the maximum output current is approximately 40 mA independent of the magnitude of V+. At values of supply voltage in excess of 15 V,
continuous short-circuits can exceed the power dissipation ratings and cause eventual destruction. Destructive dissipation can result
from simultaneous shorts on all amplifiers.
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6.7 Typical Characteristics
Figure 1. Input Voltage Range Figure 2. Input Current
Figure 3. Supply Current Figure 4. Voltage Gain
Figure 5. Open-Loop Frequency Response Figure 6. Common Mode Rejection Ratio
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Typical Characteristics (continued)
Figure 7. Voltage Follower Pulse Response Figure 8. Voltage Follower Pulse Response (Small Signal)
Figure 9. Large Signal Frequency Response Figure 10. Output Characteristics Current Sourcing
Figure 11. Output Characteristics Current Sinking Figure 12. Current Limiting
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Typical Characteristics (continued)
Figure 13. Input Current (LM2902-N Only) Figure 14. Voltage Gain (LM2902-N Only)
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7 Detailed Description
7.1 Overview
The LM124-N series are op amps which operate with only a single power supply voltage, have true-differential
inputs, and remain in the linear mode with an input common-mode voltage of 0 VDC. These amplifiers operate
over a wide range of power supply voltage with little change in performance characteristics. At 25°C amplifier
operation is possible down to a minimum supply voltage of 2.3 VDC.
7.2 Functional Block Diagram
7.3 Feature Description
The LM124 provides a compelling balance of performance versus current consumption. The 700 μA of supply
current draw over the wide operating conditions with a 1-MHz gain-bandwidth and temperature compensated
bias currents makes the LM124 an effective solution for large variety of applications. The input offset voltage of 2
mV and offset current of 5 nA, along with the 45n-A bias current across a wide supply voltage means a single
design can be used in a large number of different implementations.
7.4 Device Functional Modes
Large differential input voltages can be easily accommodated and, as input differential voltage protection diodes
are not needed, no large input currents result from large differential input voltages. The differential input voltage
may be larger than V+without damaging the device. Protection should be provided to prevent the input voltages
from going negative more than 0.3 VDC (at 25°C). An input clamp diode with a resistor to the IC input terminal
can be used.
To reduce the power supply drain, the amplifiers have a class A output stage for small signal levels which
converts to class B in a large signal mode. This allows the amplifiers to both source and sink large output
currents. Therefore both NPN and PNP external current boost transistors can be used to extend the power
capability of the basic amplifiers. The output voltage needs to raise approximately 1 diode drop above ground to
bias the on-chip vertical PNP transistor for output current sinking applications.
For ac applications, where the load is capacitively coupled to the output of the amplifier, a resistor should be
used, from the output of the amplifier to ground to increase the class A bias current and prevent crossover
distortion.
Where the load is directly coupled, as in dc applications, there is no crossover distortion.
Capacitive loads which are applied directly to the output of the amplifier reduce the loop stability margin. Values
of 50 pF can be accommodated using the worst-case non-inverting unity gain connection. Large closed loop
gains or resistive isolation should be used if larger load capacitance must be driven by the amplifier.
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Device Functional Modes (continued)
The bias network of the LM124-N establishes a drain current which is independent of the magnitude of the power
supply voltage over the range of from 3 VDC to 30 VDC.
Output short circuits either to ground or to the positive power supply should be of short time duration. Units can
be destroyed, not as a result of the short circuit current causing metal fusing, but rather due to the large increase
in IC chip dissipation which will cause eventual failure due to excessive junction temperatures. Putting direct
short-circuits on more than one amplifier at a time will increase the total IC power dissipation to destructive
levels, if not properly protected with external dissipation limiting resistors in series with the output leads of the
amplifiers. The larger value of output source current which is available at 25°C provides a larger output current
capability at elevated temperatures (see Typical Characteristics) than a standard IC op amp.
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The LM124 series of amplifiers is specified for operation from 3 V to 32 V (±1.5 V to ±16 V). Many of the
specifications apply from –40°C to 125°C. Parameters that can exhibit significant variance with regards to
operating voltage or temperature are presented in Typical Characteristics.
8.2 Typical Applications
Figure 15 emphasizes operation on only a single power supply voltage. If complementary power supplies are
available, all of the standard op amp circuits can be used. In general, introducing a pseudo-ground (a bias
voltage reference of V+/2) will allow operation above and below this value in single power supply systems. Many
application circuits are shown which take advantage of the wide input common-mode voltage range which
includes ground. In most cases, input biasing is not required and input voltages which range to ground can easily
be accommodated.
8.2.1 Non-Inverting DC Gain (0 V Input = 0 V Output)
*R not needed due to temperature independent IIN
Figure 15. Non-Inverting Amplifier with G=100
8.2.1.1 Design Requirements
For this example application, the required signal gain is a non-inverting 100x±5% with a supply voltage of 5 V.
8.2.1.2 Detailed Design Procedure
Using the equation for a non-inverting gain configuration, Av = 1+R2/R1. Setting the R1 to 10 kΩ, R2 is 99 times
larger than R1, which is 990 kΩ. A 1MΩis more readily available, and provides a gain of 101, which is within the
desired specification.
The gain-frequency characteristic of the amplifier and its feedback network must be such that oscillation does not
occur. To meet this condition, the phase shift through amplifier and feedback network must never exceed 180°
for any frequency where the gain of the amplifier and its feedback network is greater than unity. In practical
applications, the phase shift should not approach 180° since this is the situation of conditional stability. Obviously
the most critical case occurs when the attenuation of the feedback network is zero.
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Typical Applications (continued)
8.2.1.3 Application Curve
Figure 16. Non-Inverting Amplified Response Curve
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Typical Applications (continued)
8.2.2 Other Application Circuits at V+= 5.0 VDC
Where: V0=0VDC for VIN =0VDC
Where: V0= V1+ V2V3V4AV= 10
(V1+ V2)(V3+ V4) to keep VO> 0 VDC
Figure 17. DC Summing Amplifier Figure 18. Power Amplifier
(VIN'S 0 VDC And VOVDC)
fo= 1 kHz Q = 50 AV= 100 (40 dB)
Figure 19. LED Driver Figure 20. “BI-QUAD” RC Active Bandpass Filter
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Typical Applications (continued)
Figure 21. Fixed Current Sources
*(Increase R1 for ILsmall)
Figure 22. Lamp Driver Figure 23. Current Monitor
Figure 24. Driving TTL Figure 25. Voltage Follower
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Typical Applications (continued)
Figure 26. Pulse Generator Figure 27. Squarewave Oscillator
IO= 1 amp/volt VIN (Increase REfor Iosmall)
Figure 28. Pulse Generator Figure 29. High Compliance Current Sink
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Typical Applications (continued)
Figure 30. Low Drift Peak Detector Figure 31. Comparator With Hysteresis
*Wide control voltage range:
0 VDC VC2 (V+1.5 VDC)
VO= VR
Figure 32. Ground Referencing a Differenti