LM124A/LM124QML
Low Power Quad Operational Amplifiers
General Description
The LM124/124A consists of four independent, high gain,
internally frequency compensated operational amplifiers
which were designed specifically to operate from a single
power supply over a wide range of voltages. Operation from
split power supplies is also possible and the low power
supply current drain is independent of the magnitude of the
power supply voltage.
Application areas include transducer amplifiers, DC gain
blocks and all the conventional op amp circuits which now
can be more easily implemented in single power supply
systems. For example, the LM124/124A can be directly op-
erated off of the standard +5Vdc power supply voltage which
is used in digital systems and will easily provide the required
interface electronics without requiring the additional +15Vdc
power supplies.
Unique Characteristics
nIn the linear mode the input common-mode voltage
range includes ground and the output voltage can also
swing to ground, even though operated from only a
single power supply voltage
nThe unity gain cross frequency is temperature
compensated
nThe input bias current is also temperature compensated
Advantages
nEliminates need for dual supplies
nFour internally compensated op amps in a single
package
nAllows directly sensing near GND and V
OUT
also goes
to GND
nCompatible with all forms of logic
nPower drain suitable for battery operation
Features
nInternally frequency compensated for unity gain
nLarge DC voltage gain 100 dB
nWide bandwidth (unity gain) 1 MHz
(temperature compensated)
nWide power supply range:
Single supply 3V to 32V
or dual supplies ±1.5V to ±16V
nVery low supply current drain (700 µA) — essentially
independent of supply voltage
nLow input biasing current 45 nA
(temperature compensated)
nLow input offset voltage 2 mV
and offset current: 5 nA
nInput common-mode voltage range includes ground
nDifferential input voltage range equal to the power
supply voltage
nLarge output voltage swing 0V to V
+
− 1.5V
Ordering Information
NS PART NUMBER SMD PART NUMBER NS PACKAGE NUMBER PACKAGE DISCRIPTION
LM124J/883 7704301CA J14A 14LD CERDIP
LM124AE/883 77043022A E20A 20LD LEADLESS CHIP CARRIER
LM124AJ/883 7704302CA J14A 14LD CERDIP
LM124AW/883 W14B 14LD CERPACK
LM124AWG/883 7704302XA WG14A 14LD CERAMIC SOIC
LM124AJLQMLV 5962L9950401VCA,
50k rd(Si)
J14A 14LD CERDIP
LM124AJRQMLV 5962R9950401VCA,
100k rd(Si)
J14A 14LD CERDIP
LM124AWGLQMLV 5962L9950401VZA,
50k rd(Si)
WG14A 14LD CERAMIC SOIC
LM124AWGRQMLV 5962R9950401VZA,
100k rd(Si)
WG14A 14LD CERAMIC SOIC
LM124AWLQMLV 5962L9950401VDA,
50k rd(Si)
W14B 14LD CERPACK
LM124AWRQMLV 5962R9950401VDA,
100k rd(Si)
W14B 14LD CERPACK
January 2005
LM124A/LM124QML Low Power Quad Operational Amplifiers
© 2005 National Semiconductor Corporation DS201080 www.national.com
Connection Diagrams
Leadless Chip Carrier
20108055
See NS Package Number E20A
Dual-In-Line Package
20108001
Top View
See NS Package Number J14A
20108033
See NS Package Number W14B or WG14A
LM124A/LM124QML
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Schematic Diagram (Each Amplifier)
20108002
LM124A/LM124QML
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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage, V
+
32Vdc or +16Vdc
Differential Input Voltage 32Vdc
Input Voltage −0.3Vdc to +32Vdc
Input Current
(V
IN
<−0.3Vdc) (Note 4) 50 mA
Power Dissipation (Note 2)
CERDIP 1260mW
CERPACK 700mW
LCC 1350mW
CERAMIC SOIC 700mW
Output Short-Circuit to GND
(One Amplifier) (Note 3)
V
+
≤15Vdc and T
A
= 25˚C Continuous
Operating Temperature Range −55˚C ≤T
A
≤+125˚C
Maximum Junction Temperature 150˚C
Storage Temperature Range −65˚C ≤T
A
≤+150˚C
Lead Temperature (Soldering, 10 seconds) 260˚C
Thermal Resistance ThetaJA
CERDIP (Still Air) 103 C/W
(500LF/Min Air flow) 51 C/W
CERPACK (Still Air) 176 C/W
(500LF/Min Air flow) 116 C/W
LCC (Still Air) 91 C/W
(500LF/Min Air flow) 66 C/W
CERAMIC SOIC (Still Air) 176 C/W
(500LF/Min Air flow) 116 C/W
ThetaJC
CERDIP 19 C/W
CERPACK 18 C/W
LCC 24 C/W
CERAMIC SOIC 18 C/W
Package Weight (Typical)
CERDIP TBD
CERPACK TBD
LCC TBD
CERAMIC SOIC 410mg
ESD Tolerance (Note 5) 250V
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed
specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test
conditions.
Note 2: The maximum power dissipation must be derated at elevated temperatures and is dictated by Tjmax (maximum junction temperature), ThetaJA (package
junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any temperature is Pdmax = (Tjmax -
TA)/ThetaJA or the number given in the Absolute Maximum Ratings, whichever is lower.
Note 3: 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 40mA independent of the magnitude of V+. At values of supply voltage in excess of +15Vdc, continuous short-circuits can exceed the power
dissipation ratings and cause eventual destruction. Destructive dissipation can result from simultaneous shorts on all amplifiers.
Note 4: 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 -0.3Vdc (at 25 C).
Note 5: Human body model, 1.5 kΩin series with 100 pF.
LM124A/LM124QML
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Quality Conformance Inspection
MIL-STD-883, Method 5005 — Group A
Subgroup Description Temp ( ˚C)
1 Static tests at +25
2 Static tests at +125
3 Static tests at -55
4 Dynamic tests at +25
5 Dynamic tests at +125
6 Dynamic tests at -55
7 Functional tests at +25
8A Functional tests at +125
8B Functional tests at -55
9 Switching tests at +25
10 Switching tests at +125
11 Switching tests at -55
LM124A/LM124QML
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LM124A 883 DC Electrical Characteristics
(The following conditions apply to all the following parameters, unless otherwise specified.) All voltages referenced to device
ground.
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
Icc Power Supply Current V+ = 5V 1.2 mA 1, 2, 3
V+ = 30V 3.0 mA 1
4.0 mA 2, 3
Isink Output Sink Current V+ = 15V, Vout = 200mV,
+Vin = 0mV, -Vin = +65mV
12 uA 1
V+ = 15V, Vout = 2V,
+Vin = 0mV, -Vin = +65mV
10 mA 1
5mA2,3
Isource Output Source
Current
V+ = 15V, Vout = 2V,
+Vin = 0mV, -Vin = -65mV
-20 mA 1
-10 mA 2, 3
Ios Short Circuit Current V+ = 5V, Vout = 0V -60 mA 1
Vio Input Offset Voltage V+ = 30V, Vcm = 0V -2 2 mV 1
-4 4 mV 2, 3
V+ = 30V, Vcm = 28.5V -2 2 mV 1
V+ = 30V, Vcm = 28V -4 4 mV 2, 3
V+ = 5V, Vcm = 0V -2 2 mV 1
-4 4 mV 2, 3
CMRR Common Mode
Rejection Ratio
V+ = 30V, Vin = 0V to 28.5V 70 dB 1
±Iib Input Bias Current V+ = 5V, Vcm = 0V -50 10 nA 1
-100 10 nA 2, 3
Iio Input Offset Current V+ = 5V, Vcm = 0V -10 10 nA 1
-30 30 nA 2, 3
PSRR Power Supply
Rejection Ratio
V+ = 5V to 30V, Vcm = 0V 65 dB 1
Vcm Common Mode
Voltage Range
V+ = 30V (Note 6) 28.5 V 1
(Note 6) 28 V 2, 3
Avs Large Signal Gain V+ = 15V, Rl = 2K Ohms,
Vo=1Vto11V
(Note 7) 50 V/mV 4
(Note 7) 25 V/mV 5, 6
Voh Output Voltage High V+ = 30V, Rl = 2K Ohms 26 V 4, 5, 6
V+ = 30V, Rl = 10K Ohms 27 V 4, 5, 6
Vol Output Voltage Low V+ = 30V, Rl = 10K Ohms 40 mV 4, 5, 6
V+ = 30V, Isink = 1uA 40 mV 4
100 mV 5, 6
V+ = 5V, Rl = 10K Ohms 20 mV 4, 5, 6
Channel Separation
Amp to Amp Coupling
1KHz, 20KHz (Note 8) 80 dB 4
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LM124 883 DC Electrical Characteristics
(The following conditions apply to all the following parameters, unless otherwise specified.) All voltages referenced to device
ground.
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
Icc Power Supply Current V+ = 5V 1.2 mA 1, 2, 3
V+ = 30V 3.0 mA 1
4.0 mA 2, 3
Isink Output Sink Current V+ = 15V, Vout = 200mV,
+Vin = 0mV, -Vin = +65mV
12 uA 1
V+ = 15V, Vout = 2V,
+Vin = 0mV, -Vin = +65mV
10 mA 1
5mA2,3
Isource Output Source
Current
V+ = 15V, Vout = 2V,
+Vin = 0mV, -Vin = -65mV
-20 mA 1
-10 mA 2, 3
Ios Short Circuit Current V+ = 5V, Vout = 0V -60 mA 1
Vio Input Offset Voltage V+ = 30V, Vcm = 0V -5 5 mV 1
-7 7 mV 2, 3
V+ = 30V, Vcm = 28V -5 5 mV 1
-7 7 mV 2, 3
V+ = 5V, Vcm = 0V -5 5 mV 1
-7 7 mV 2, 3
V+ = 30V, Vcm = 28.5V -5 5 mV 1
CMRR Common Mode
Rejection Ratio
V+ = 30V, Vin = 0V to 28.5V 70 dB 1
+Iib Input Bias Current V+ = 5V, Vcm = 0V -150 10 nA 1
-300 10 nA 2, 3
Iio Input Offset Current V+ = 5V, Vcm = 0V -30 30 nA 1
-100 100 nA 2, 3
PSRR Power Supply
Rejection Ratio
V+ = 5V to 30V, Vcm = 0V 65 dB 1
Vcm Common Mode
Voltage Range
V+ = 30V (Note 6) 28.5 V 1
(Note 6) 28 V 2, 3
Avs Large Signal Gain V+ = 15V, Rl = 2K Ohms,
Vo=1Vto11V
50 V/mV 4
25 V/mV 5, 6
Voh Output Voltage High V+ = 30V, Rl = 2K Ohms 26 V 4, 5, 6
V+ = 30V, Rl = 10K Ohms 27 V 4, 5, 6
Vol Output Voltage Low V+ = 30V, Rl = 10K Ohms 40 mV 4, 5, 6
V+ = 30V, Isink = 1uA 40 mV 4
100 mV 5, 6
V+ = 5V, Rl = 10K Ohms 20 mV 4, 5, 6
Channel Separation
(Amp to Amp
Coupling)
1KHz, 20KHz (Note 8) 80 dB 4
LM124A/LM124QML
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LM124A RAD HARD DC Electrical Characteristics (Note 10)
(The following conditions apply to all the following parameters, unless otherwise specified.) All voltages referenced to device
ground.
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
Vio Input Offset Voltage Vcc+ = 30V, Vcc- = Gnd,
Vcm = -15V
-2 2 mV 1
-4 4 mV 2, 3
Vcc+ = 2V, Vcc- = -28V,
Vcm = 13V
-2 2 mV 1
-4 4 mV 2, 3
Vcc+ = 5V, Vcc- = Gnd,
Vcm = -1.4V
-2 2 mV 1
-4 4 mV 2, 3
Vcc+ = 2.5V, Vcc- = -2.5,
Vcm = 1.1V
-2 2 mV 1
-4 4 mV 2, 3
Iio Input Offset Current Vcc+ = 30V, Vcc- = Gnd,
Vcm = -15V
-10 10 nA 1, 2
-30 30 nA 3
Vcc+ = 2V, Vcc- = -28V,
Vcm = 13V
-10 10 nA 1, 2
-30 30 nA 3
Vcc+ = 5V, Vcc- = Gnd,
Vcm = -1.4V
-10 10 nA 1, 2
-30 30 nA 3
Vcc+ = 2.5V, Vcc- = -2.5,
Vcm = 1.1V
-10 10 nA 1, 2
-30 30 nA 3
±Iib Input Bias Current Vcc+ = 30V, Vcc- = Gnd,
Vcm = -15V
-50 +0.1 nA 1, 2
-100 +0.1 nA 3
Vcc+ = 2V, Vcc- = -28V,
Vcm = 13V
-50 +0.1 nA 1, 2
-100 +0.1 nA 3
Vcc+ = 5V, Vcc- = Gnd,
Vcm = -1.4V
-50 +0.1 nA 1, 2
-100 +0.1 nA 3
Vcc+ = 2.5V, Vcc- = -2.5,
Vcm = 1.1V
-50 +0.1 nA 1, 2
-100 +0.1 nA 3
+PSRR Power Supply
Rejection Ratio
Vcc- = Gnd, Vcm = -1.4V,
5V ≤Vcc ≤30V
-100 100 uV/V 1, 2, 3
CMRR Common Mode
Rejection Ratio
76 dB 1, 2, 3
Ios+ Output Short Circiut
Current
Vcc+ = 30V, Vcc- = Gnd,
Vo = 25V
-70 mA 1, 2,3
Icc Power Supply Current Vcc+ = 30V, Vcc- = Gnd 3 mA 1, 2
4mA3
Delta Vio/
Delta T
Input Offset Voltage
Temperature
Sensitivity
+25˚C ≤TA ≤+125˚C,
+Vcc = 5V, -Vcc = 0V,
Vcm = -1.4V
(Note 9) -30 30 uV/ ˚C 2
-55˚C ≤TA ≤+25˚C, +Vcc = 5V,
-Vcc = 0V, Vcm = -1.4V
(Note 9) -30 30 uV/ ˚C 3
Delta Iio/
Delta T
Input Offset Current
Temperature
Sensitivity
+25˚C ≤TA ≤+125˚C,
+Vcc = 5V, -Vcc = 0V,
Vcm = -1.4V
(Note 9) -400 400 pA/˚ C 2
-55˚C ≤TA ≤+25˚C, +Vcc = 5V,
-Vcc = 0V, Vcm = -1.4V
(Note 9) -700 700 pA/ ˚C 3
LM124A/LM124QML
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LM124A RAD HARD AC/DC Electrical Characteristics (Note 10)
(The following conditions apply to all the following parameters, unless otherwise specified.) All voltages referenced to device
ground.
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
Vol Logical "0" Output
Voltage
Vcc+ = 30V, Vcc- = Gnd,
Rl = 10K Ohms
35 mV 4, 5, 6
Vcc+ = 30V, Vcc- = Gnd,
Iol = 5mA
1.5 V 4,5,6
Vcc+ = 4.5V, Vcc- = Gnd,
Iol = 2uA
0.4 V 4,5,6
Voh Logical "1" Output
Voltage
Vcc+ = 30V, Vcc- = Gnd,
Ioh = -10mA
27 V 4,5,6
Vcc+ = 4.5V, Vcc- = Gnd,
Ioh = -10mA
2.4 V 4,5,6
Avs+ Voltage Gain
Vcc+ = 30V, Vcc- = Gnd,
1V ≤Vo ≤26V, Rl = 10K Ohms
50 V/mV 4
25 V/mV 5, 6
Vcc+ = 30V, Vcc- = Gnd,
5V ≤Vo ≤20V, Rl = 2K Ohms
50 V/mV 4
25 V/mV 5, 6
Avs Voltage Gain Vcc+ = 5V, Vcc- = Gnd,
1V ≤Vo ≤2.5V, Rl = 10K Ohms
10 V/mV 4, 5, 6
Vcc+ = 5V, Vcc- = Gnd,
1V ≤Vo ≤2.5V, Rl = 2K Ohms
10 V/mV 4, 5, 6
+Vop Maximum Output
Voltage Swing
Vcc+ = 30V, Vcc- = Gnd,
Vo = +30V, Rl = 10K Ohms
27 V 4,5,6
Vcc+ = 30V, Vcc- = Gnd,
Vo = +30V, Rl = 2K Ohms
26 V 4,5,6
TR(tr) Transient Response:
Rise Time
Vcc+ = 30V, Vcc- = Gnd 1 uS 7, 8A, 8B
TR(os) Transient Response:
Overshoot
Vcc+ = 30V, Vcc- = Gnd 50 % 7, 8A, 8B
±Sr Slew Rate: Rise Vcc+ = 30V, Vcc- = Gnd 0.1 V/uS 7, 8A, 8B
Slew Rate: Fall Vcc+ = 30V, Vcc- = Gnd 0.1 V/uS 7, 8A, 8B
LM124A/LM124QML
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LM124A RAD HARD — AC Electrical Characteristics (Note 10)
(The following conditions apply to all the following parameters, unless otherwise specified.) AC: +Vcc = 30V, -Vcc = 0V
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
NI(BB) Noise Broadband +Vcc = 15V, -Vcc = -15V,
BW = 10Hz to 5KHz
15 uVrm s 7
NI(PC) Noise Popcorn +Vcc = 15V, -Vcc = -15V,
Rs = 20K Ohms,
BW = 10Hz to 5KHz
50 uVpK 7
Cs Channel Separation +Vcc = 30V, -Vcc = Gnd,
Rl = 2K Ohms
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,AtoB
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,AtoC
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,AtoD
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,BtoA
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,BtoC
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,BtoD
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,CtoA
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,CtoB
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,CtoD
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,DtoA
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,DtoB
80 dB 7
Rl = 2K Ohms,
Vin=1Vand16V,DtoC
80 dB 7
LM124A/LM124QML
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LM124A RAD HARD — DC Drift Values (Note 10)
(The following conditions apply to all the following parameters, unless otherwise specified.) DC: "Delta calculationsperformed
on QMLV devices at group B, subgroup 5 only"
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
Vio Input Offset Voltage Vcc+ = 30V, Vcc- = Gnd,
Vcm = -15V
-0.5 0.5 mV 1
±Iib Input Bias Current Vcc+ = 30V, Vcc- = Gnd,
Vcm = -15V
-10 10 nA 1
Electrical Characteristics — POST RADIATION LIMITS +25˚C (Note 10)
(The following conditions apply to all the following parameters, unless otherwise specified.) All voltages referenced to device
ground.
SYMBOL PARAMETER CONDITIONS NOTES MIN MAX UNIT SUB-
GROUPS
Vio Input Offset Voltage Vcc+ = 30V, Vcc- = Gnd,
Vcm = -15V
(Note 10) -2.5 2.5 mV 1
Vcc+ = 2V, Vcc- = -28V,
Vcm = 13V
(Note 10) -2.5 2.5 mV 1
Vcc+ = 5V, Vcc- = GND,
Vcm = -1.4V
(Note 10) -2.5 2.5 mV 1
Vcc+ = 2.5V, Vcc- = -2.5,
Vcm = 1.1V
(Note 10) -2.5 2.5 mV 1
Iio Input Offset Current Vcc+ = 30V, Vcc- = GND,
Vcm = -15V
(Note 10) -15 15 nA 1
Vcc+ = 2V, Vcc- = -28V,
Vcm = 13V
(Note 10) -15 15 nA 1
Vcc+ = 5V, Vcc- = GND,
Vcm = -1.4V
(Note 10) -15 15 nA 1
Vcc+ = 2.5V, Vcc- = -2.5V,
Vcm = 1.1V
(Note 10) -15 15 nA 1
±Iib Input Bias Current Vcc+ = 30V, Vcc- = GND,
Vcm = -15V
(Note 10) -75 +0.1 nA 1
Vcc+ = 2V, Vcc- = -28V,
Vcm = 13V
(Note 10) -75 +0.1 nA 1
Vcc+ = 5V, Vcc- = GND,
Vcm = -1.4V
(Note 10) -75 +0.1 nA 1
Vcc+ = 2.5V, Vcc- = -2.5V,
Vcm = 1.1V
(Note 10) -75 +0.1 nA 1
Avs+ Voltage Gain Vcc+ = 30V, Vcc- = GND,
1V ≤Vo ≤26V, Rl = 10K Ohms
(Note 10) 40 V/mV 4
Vcc+ = 30V, Vcc- = GND,
5V ≤Vo ≤20V, Rl = 2K Ohms
(Note 10) 40 V/mV 4
Note 6: Guaranteed by Vio tests.
Note 7: Datalog reading in K=V/mV
Note 8: Guaranteed, not tested
Note 9: Calculated parameters
Note 10: Pre and post irradiation limits are identical to those listed under AC and DC electrical characteristics except as listed in the Post Radiation Limits Table.
These parts may be dose rate sensitive in a space environment and demonstrate enhanced low dose rate effect. Radiation end point limits for the noted parameters
are guaranteed only for the conditions as specified in MIL-STD-883, Method 1019
LM124A/LM124QML
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Typical Performance Characteristics
Input Voltage Range Input Current
20108034 20108035
Supply Current Voltage Gain
20108036 20108037
Open Loop Frequency
Response
Common Mode Rejection
Ratio
20108038
20108039
LM124A/LM124QML
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Typical Performance Characteristics (Continued)
Voltage Follower Pulse
Response
Voltage Follower Pulse
Response (Small Signal)
20108040 20108041
Large Signal Frequency
Response
Output Characteristics
Current Sourcing
20108042 20108043
Output Characteristics
Current Sinking Current Limiting
20108044 20108045
LM124A/LM124QML
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Application Hints
The LM124 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 V
DC
. 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 V
DC
.
The pinouts of the package have been designed to simplify
PC board layouts. Inverting inputs are adjacent to outputs for
all of the amplifiers and the outputs have also been placed at
the corners of the package (pins 1, 7, 8, and 14).
Precautions should be taken to insure that the power supply
for the integrated circuit never becomes reversed in polarity
or that the unit is not inadvertently installed backwards in a
test socket as an unlimited current surge through the result-
ing forward diode within the IC could cause fusing of the
internal conductors and result in a destroyed unit.
Large differential input voltages can be easily accommo-
dated and, as input differential voltage protection diodes are
not needed, no large input currents result from large differ-
ential 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 V
DC
(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.
The bias network of the LM124 establishes a drain current
which is independent of the magnitude of the power supply
voltage over the range of from 3 V
DC
to 30 V
DC
.
Output short circuits either to ground or to the positive power
supply should be of short time duration. Units can be de-
stroyed, 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 exces-
sive 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 pro-
tected 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 performance characteristics) than a standard IC
op amp.
The circuits presented in the section on typical applications
emphasize 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, introduc-
ing 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.
LM124A/LM124QML
www.national.com 14
Typical Single-Supply Applications
(V
+
= 5.0 V
DC
)
Non-Inverting DC Gain (0V Input = 0V Output)
20108005
*R not needed due to temperature independent IIN
DC Summing Amplifier
(V
IN’S
≥0V
DC
and V
O
≥V
DC
) Power Amplifier
20108006
Where: V0=V
1+V
2−V
3−V
4
(V1+V
2)≥(V3+V
4) to keep VO>0V
DC
20108007
V0=0V
DC for VIN =0V
DC
AV=10
LM124A/LM124QML
www.national.com15
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
LED Driver “BI-QUAD” RC Active Bandpass Filter
20108008
20108009
fo= 1 kHz
Q=50
AV= 100 (40 dB)
Fixed Current Sources Lamp Driver
20108010
20108011
LM124A/LM124QML
www.national.com 16
Typical Single-Supply Applications
(V+= 5.0 V
DC
) (Continued)
Current Monitor
20108012
*(Increase R1 for ILsmall)
Driving TTL
20108013
Voltage Follower
20108014
Pulse Generator
20108015
Squarewave Oscillator
20108016
Pulse Generator
20108017
LM124A/LM124QML
www.national.com17
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
High Compliance Current Sink
20108018
IO= 1 amp/volt VIN
(Increase REfor Iosmall)
Low Drift Peak Detector
20108019
LM124A/LM124QML
www.national.com 18
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
Comparator with Hysteresis Ground Referencing a Differential Input Signal
20108020
20108021
VO=V
R
Voltage Controlled Oscillator Circuit
20108022
*Wide control voltage range: 0 VDC ≤VC≤2(V
+−1.5 VDC)
Photo Voltaic-Cell Amplifier
20108023
LM124A/LM124QML
www.national.com19
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
AC Coupled Inverting Amplifier
20108024
AC Coupled Non-Inverting Amplifier
20108025
LM124A/LM124QML
www.national.com 20
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
DC Coupled Low-Pass RC Active Filter
20108026
fO= 1 kHz
Q=1
AV=2
High Input Z, DC Differential Amplifier
20108027
LM124A/LM124QML
www.national.com21
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
High Input Z Adjustable-Gain
DC Instrumentation Amplifier
20108028
Using Symmetrical Amplifiers to
Reduce Input Current (General Concept)
20108029
Bridge Current Amplifier
20108030
LM124A/LM124QML
www.national.com 22
Typical Single-Supply Applications (V
+
= 5.0 V
DC
) (Continued)
Bandpass Active Filter
20108031
fO= 1 kHz
Q=25
LM124A/LM124QML
www.national.com23
Revision History Section
Date
Released Revision Section Originator Changes
9–2–04 A New Release, Corporate format R. Malone 3 MDS data sheets converted into one
Corp. data sheet format. MNLM124-X,
Rev. 1A2, MNLM124A-X, Rev. 1A3 and
MRLM124A-X-RH, Rev. 5A0. MDS data
sheets will be archived.
01/27/05 B Connection Diagrams, Quality
Conformance Inspection Section,
and Physical Dimensions drawings
R. Malone Added E package Connection Diagram.
Changed verbiage under Quality
Conformance Title, and Updated
Revisions for the Marketing Drawings.
LM124A/LM124QML
www.national.com 24
Physical Dimensions inches (millimeters) unless otherwise noted
SAMPLE TEXT Ceramic Dual-In-Line Package (J)
NS Package Number J14A
SAMPLE TEXT 20 Pin Leadless Chip Carrier, Type C (E)
NS Package Number E20A
LM124A/LM124QML
www.national.com25
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
SAMPLE TEXT Ceramic Flatpak Package
NS Package Number W14B
SAMPLE TEXT 14-Pin Ceramic Package (WG)
NS Package Number WG14A
LM124A/LM124QML
www.national.com 26
Notes
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.
For the most current product information visit us at www.national.com.
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS
WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body, or
(b) support or sustain life, and whose failure to perform when
properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to result
in a significant injury to the user.
2. A critical component is any component of a life support
device or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship
Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned
Substances’’ as defined in CSP-9-111S2.
National Semiconductor
Americas Customer
Support Center
Email: new.feedback@nsc.com
Tel: 1-800-272-9959
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Europe Customer Support Center
Fax: +49 (0) 180-530 85 86
Email: europe.support@nsc.com
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Fax: 81-3-5639-7507
Email: jpn.feedback@nsc.com
Tel: 81-3-5639-7560
www.national.com
LM124A/LM124QML Low Power Quad Operational Amplifiers
