LM321
www.ti.com
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
LM321 Low Power Single Op Amp
Check for Samples: LM321
1FEATURES DESCRIPTION
The LM321 brings performance and economy to low
2• (VCC = 5V, TA= 25°C. Typical values unless power systems. With a high unity gain frequency and
specified.) a specified 0.4V/µs slew rate, the quiescent current is
• Gain-Bandwidth Product 1MHz only 430µA/amplifier (5V). The input common mode
• Low Supply Current 430µA range includes ground and therefore the device is
able to operate in single supply applications as well
• Low Input Bias Current 45nA as in dual supply applications. It is also capable of
• Wide Supply Voltage Range +3V to +32V comfortably driving large capacitive loads.
• Stable With High Capacitive Loads The LM321 is available in the SOT-23 package.
• Single Version of LM324 Overall the LM321 is a low power, wide supply range
performance op amp that can be designed into a
APPLICATIONS wide range of applications at an economical price
without sacrificing valuable board space.
• Chargers
• Power Supplies
• Industrial: Controls, Instruments
• Desktops
• Communications Infrastructure
Connection Diagram Application Circuit
SOT-23 DC Summing Amplifier
(VIN's ≥0 VDC and VO≥VDC)
Top View
Where: V0= V1+ V2- V3- V4, (V1+V2)≥
(V3+ V4) to keep VO> 0 VDC
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2001–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
LM321
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
Absolute Maximum Ratings (1)
Differential Input Voltage ±Supply Voltage
Input Current (VIN <−0.3V) (2) 50mA
Supply Voltage (V+- V−) 32V
Input Voltage −0.3V to +32V
Output Short Circuit to GND,
V+≤15V and TA= 25°C (3) Continuous
Storage Temperature Range −65°C to 150°C
Junction Temperature (4) 150°C
Mounting Temperature
Lead Temp (Soldering, 10 sec) 260°C
Infrared (10 sec) 215°C
Thermal Resistance to Ambient (θJA) 265°C/W
ESD Tolerance (5) 300V
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not ensured. For ensured specifications and the test
conditions, see the Electrical Characteristics.
(2) 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 −0.36V (at
25°C).
(3) Short circuits from the output 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 +15V,
continuous short circuits can exceed the power dissipation ratings and cause eventual destruction.
(4) The maximum power dissipation is a function of TJ(MAX),θJA , and TA. The maximum allowable power dissipation at any ambient
temperature is PD= (TJ(MAX) - TA)/ θJA. All numbers apply for packages soldered directly onto a PC board.
(5) Human Body Model, 1.5kΩin series with 100pF.
Operating Ratings (1)
Temperature Range −40°C to 85°C
Supply Voltage 3V to 30V
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not ensured. For ensured specifications and the test
conditions, see the Electrical Characteristics.
2Submit Documentation Feedback Copyright © 2001–2013, Texas Instruments Incorporated
Product Folder Links: LM321
LM321
www.ti.com
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
Electrical Characteristics
Unless otherwise specified, all limits specified for at TA= 25°C; V+= 5V, V−= 0V, VO= 1.4V. Boldface limits apply at
temperature extremes.
Symbol Parameter Conditions Min Typ Max Units
(1) (2) (1)
VOS Input Offset Voltage (3) 2 7 mV
9
IOS Input Offset Current 5 50 nA
150
IBInput Bias Current (4) 45 250 nA
500
VCM Input Common-Mode Voltage Range V+= 30V (5) 0 V+- 1.5 V
For CMRR > = 50dB V+-2
AVLarge Signal Voltage Gain (V+= 15V, RL= 2kΩ25 100 V/mV
VO= 1.4V to 11.4V) 15
PSRR Power Supply Rejection Ratio RS≤10kΩ, 65 100 dB
V+≤5V to 30V
CMRR Common Mode Rejection Ratio RS≤10kΩ65 85 dB
VOOutput Swing VOH V+= 30V, RL= 2kΩ26 V
V+= 30V, RL= 10kΩ27 28
VOL V+= 5V, RL= 10kΩ5 20 mV
ISSupply Current, No Load V+= 5V 0.430 1.15 mA
0.7 1.2
V+= 30V 0.660 2.85
1.5 3
ISOURCE Output Current Sourcing VID = +1V, V+= 15V, 20 40 mA
VO= 2V 10 20
ISINK Output Current Sinking VID =−1V 10 20
V+= 15V, VO= 2V 5 8 mA
VID =−1V
V+= 15V, VO= 0.2V 12 100 µA
IOOutput Short Circuit to Ground V+= 15V 40 85 mA
(6)
SR Slew Rate V+= 15V, RL= 2kΩ,
VIN = 0.5 to 3V 0.4 V/µs
CL= 100pF, Unity Gain
GBW Gain Bandwidth Product V+= 30V, f = 100kHz,
VIN = 10mV, RL=2kΩ, 1 MHz
CL= 100pF
φm Phase Margin 60 deg
THD Total Harmonic Distortion f = 1kHz, AV= 20dB
RL= 2kΩ, VO= 2VPP, 0.015 %
CL= 100pF, V+= 30V
enEquivalent Input Noise Voltage f = 1kHz, RS= 100Ω40 nV/
V+= 30V
(1) All limits are specified by testing or statistical analysis.
(2) Typical values represent the most likely parametric norm.
(3) VO≅1.4V, RS= 0Ωwith V+from 5V to 30V; and over the full input common-mode range (0V to V+- 1.5V) at 25°C.
(4) 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.
(5) The input common-mode voltage of either input signal voltage should not be allowed to go negative by more than 0.3V (at 25°C). The
upper end of the common-mode voltage range is V+- 1.5V at 25°C, but either or both inputs can go to +32V without damage,
independent of the magnitude of V+.
(6) Short circuits from the output 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 +15V,
continuous short circuits can exceed the power dissipation ratings and cause eventual destruction.
Copyright © 2001–2013, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: LM321
LM321
www.ti.com
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
Typical Performance Characteristics
Unless otherwise specified, VS= +5V, single supply, TA= 25°C.
Small Signal Pulse Response Large Signal Pulse Response
Supply Current Sinking Current
vs. vs.
Supply Voltage Output Voltage
Source Current
vs.
Output Voltage Open Loop Frequency Response
Copyright © 2001–2013, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: LM321
LM321
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
www.ti.com
APPLICATION HINTS
The LM321 op amp can operate with a single or dual power supply voltage, has true-differential inputs, and
remain in the linear mode with an input common-mode voltage of 0 VDC. This amplifier operates over a wide
range of power supply voltages, with little change in performance characteristics. At 25°C amplifier operation is
possible down to a minimum supply voltage of 3V.
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 amplifier has 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 to reduce distortion.
Capacitive loads which are applied directly to the output of the amplifier reduce the loop stability margin. Values
of 50pF can be accommodated using the worst-case non-inverting unity gain connection. Large closed loop
gains or resistive isolation should be used if large load capacitance must be driven by the amplifier.
The bias network of the LM321 establishes a supply 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. The larger value
of output source current which is available at 25°C provides a larger output current capability at elevated
temperatures 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, 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.
6Submit Documentation Feedback Copyright © 2001–2013, Texas Instruments Incorporated
Product Folder Links: LM321
LM321
www.ti.com
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
TYPICAL APPLICATIONS
Non-Inverting DC Gain (0V Input = 0V Output)
DC Summing Amplifier (V)
Amplitude Modulator Circuit (IN's ≥0 VDC and VO≥VDC)
Where: V0= V1+ V2- V3- V4, (V1+V2)≥(V3+ V4) to keep VO> 0
VDC
Power Amplifier LED Driver
V0= 0 VDC for VIN = 0 VDC, AV= 10
Copyright © 2001–2013, Texas Instruments Incorporated Submit Documentation Feedback 7
Product Folder Links: LM321
LM321
www.ti.com
SNOS935B –FEBRUARY 2001–REVISED MARCH 2013
REVISION HISTORY
Changes from Revision A (March 2013) to Revision B Page
• Changed layout of National Data Sheet to TI format ............................................................................................................ 8
Copyright © 2001–2013, Texas Instruments Incorporated Submit Documentation Feedback 9
Product Folder Links: LM321
PACKAGE OPTION ADDENDUM
www.ti.com 11-Apr-2013
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
(4)
Samples
LM321MF ACTIVE SOT-23 DBV 5 1000 TBD Call TI Call TI -40 to 85 A63A
LM321MF/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 A63A
LM321MFX ACTIVE SOT-23 DBV 5 3000 TBD Call TI Call TI -40 to 85 A63A
LM321MFX/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 A63A
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a
continuation of the previous line and the two combined represent the entire Top-Side Marking for that device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
PACKAGE OPTION ADDENDUM
www.ti.com 11-Apr-2013
Addendum-Page 2
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LM321MF SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LM321MF/NOPB SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LM321MFX SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LM321MFX/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
PACKAGE MATERIALS INFORMATION
www.ti.com 14-Mar-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM321MF SOT-23 DBV 5 1000 210.0 185.0 35.0
LM321MF/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0
LM321MFX SOT-23 DBV 5 3000 210.0 185.0 35.0
LM321MFX/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 14-Mar-2013
Pack Materials-Page 2
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of
non-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products Applications
Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive
Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications
Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers
DLP® Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps
DSP dsp.ti.com Energy and Lighting www.ti.com/energy
Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial
Interface interface.ti.com Medical www.ti.com/medical
Logic logic.ti.com Security www.ti.com/security
Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense
Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video
RFID www.ti-rfid.com
OMAP Applications Processors www.ti.com/omap TI E2E Community e2e.ti.com
Wireless Connectivity www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2013, Texas Instruments Incorporated
