Datasheet LM321MFX, LM321MF, LM321H Datasheet (NSC)

LM321
Low Power Single Op Amp

LM321 Low Power Single Op Amp

April 2001

General Description

The LM321 brings performance and economy to low power
systems. With a high unity gain frequency and a guaranteed

0.4V/µs slew rate, the quiescent current is only
430µA/amplifier (5V). The input common mode range in­cludes ground and therefore the device is able to operate in
single supply applications as well as in dual supply applica­tions. It is also capable of comfortably driving large capaci­tive loads.

The LM321 is available in the SOT23-5 package. Overall the
LM321 is a low power, wide supply range performance op
amp that can be designed into a wide range of applications
at an economical price without sacrificing valuable board
space.

Connection Diagram

SOT23-5

Features

(VCC=5V,TA= 25˚C. Typical values unless specified).

n Gain-Bandwidth product 1MHz
n Low supply current 430µA
n Low input bias current 45nA
n Wide supply voltage range +3V to +32V
n Stable with high capacitive loads
n Single version of LM324

Applications

n Chargers
n Power supplies
n Industrial: controls, instruments
n Desktops
n Communications infrastructure

Application Circuit

DC Summing Amplifier

(V

≥ 0VDCand VO≥ VDC)

IN’s

Top View

20007601

Where: V0=V1+V2-V3-V4,(V1+V2)≥(V3+V4) to keep V

O

20007607

>

0V

DC

Ordering Information

Package Part Number Package Marking Transport Media NSC Drawing

5-Pin SOT-23 LM321MF A63A 1k Units Tape and Reel MF05A

LM321MFX 3k Units Tape and Reel

© 2001 National Semiconductor Corporation DS200076 www.national.com

Absolute Maximum Ratings (Note 1)

LM321

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Differential Input Voltage
Input Current (V
Supply Voltage (V

<

−0.3V) (Note 6) 50mA

IN

+-V−

) 32V
Input Voltage −0.3V to +32V
Output Short Circuit to GND,

+

V

≤ 15V and TA= 25˚C (Note 2) Continuous

Storage Temperature Range −65˚C to 150˚C

±

Supply Voltage

Junction Temperature (Note 3) 150˚C

Mounting Temperature

Lead Temp (Soldering, 10 sec) 260˚C
Infrared (10 sec) 215˚C

Thermal Resistance to Ambient (θ

) 265˚C/W

JA

ESD Tolerance (Note 10) 300V

Operating Ratings (Note 1)

Temperature Range −40˚C to 85˚C
Supply Voltage 3V to 30V

Electrical Characteristics Unless otherwise specified, all limits guaranteed for at T

0V, V

= 1.4V. Boldface limits apply at temperature extremes.

O

Symbol Parameter Conditions Min

(Note 5)

V

OS

Input Offset Voltage (Note 7) 2 7

= 25˚C; V+= 5V, V−=

A

Typ

(Note 4)

(Note 5)

Max

Units

mV

9

I

OS

Input Offset Current 5 50

nA

150

I

B

Input Bias Current (Note 8) 45 250

nA

500

V

CM

A

V

Input Common-Mode Voltage Range V+= 30V (Note 9)

Large Signal Voltage Gain (V+= 15V, RL=2kΩ

PSRR Power Supply Rejection Ratio R

CMRR Common Mode Rejection Ratio R
V

O

I

S

I

SOURCE

I

SINK

I

O

Output Swing V

OH

V

OL

Supply Current, No Load V+= 5V 0.430

Output Current Sourcing VID= +1V, V+= 15V,

Output Current Sinking VID= −1V

Output Short Circuit to Ground

0V

>

For CMRR

= 1.4V to 11.4V)

V

O

≤ 10kΩ,

S
+

≤ 5V to 30V

V

≤ 10kΩ 65 85 dB

S

= 50dB

25

100 V/mV

15

65 100 dB

V+= 30V, RL=2kΩ 26

+

= 30V, RL= 10kΩ 27 28

V
V+= 5V, RL= 10kΩ 520mV

0.7

+

V

= 30V 0.660

1.5

20

=2V

V

O

10

10

+

= 15V, VO=2V

V
V

= −1V

ID
+

= 15V, VO= 0.2V 12 100 µA

V

5

40

20

20

8 mA

V+= 15V 40 85 mA

+

- 1.5

+

-2

V

1.15

1.2

2.85

3

V

V

mA

mA

(Note 2)

SR Slew Rate V

GBW Gain Bandwidth Product V

+

= 15V, RL=2kΩ,

= 0.5 to 3V

V

IN

= 100pF, Unity Gain

C

L
+

= 30V, f = 100kHz,

= 10mV, RL=2kΩ,

V

IN

= 100pF

C

L

0.4 V/µs

1 MHz

φm Phase Margin 60 deg

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LM321

Electrical Characteristics Unless otherwise specified, all limits guaranteed for at T

0V, V

= 1.4V. Boldface limits apply at temperature extremes. (Continued)

O

Symbol Parameter Conditions Min

(Note 5)

THD Total Harmonic Distortion f = 1kHz, A

=2kΩ,VO=2VPP,

R

L

= 100pF, V+= 30V

C

L

e

n

Note 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 guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.

Note 2: Short circuits from the output V
current is approximately 40mA independent of the magnitude of V
dissipation ratings and cause eventual destruction.

Note 3: The maximum power dissipation is a function of T
P

D

Note 4: Typical values represent the most likely parametric norm.
Note 5: All limits are guaranteed by testing or statistical analysis.
Note 6: 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
duration that an input is driven negative. This is not destructive and normal outputstateswillre-establishwhentheinputvoltage,which was negative, again returns
to a value greater than −0.36V (at 25˚C).

Note 7: V
Note 8: 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 outputso

no loading change exists on the input lines.
Note 9: 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
Note 10: Human Body Model, 1.5kΩ in series with 100pF.

Equivalent Input Noise Voltage f = 1kHz, RS= 100Ω

+

= 30V

V

+

can cause excessive heating and eventual destruction. When considering short circuits to ground the maximum output

=(T

J(MAX)-TA

)/ θJA. All numbers apply for packages soldered directly onto a PC board.

≅ 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.

O

+

- 1.5V at 25˚C, but either or both inputs can go to +32V without damage, independent of the magnitude of V+.

+

. At values of supply voltage in excess of +15V, continuous short circuits can exceed the power

, θJA, and TA. The maximum allowable power dissipation at any ambient temperature is

J(MAX)

= 20dB

V

+

voltage level (or to ground for a large overdrive) for the time

= 25˚C; V+= 5V, V−=

A

Typ

(Note 4)

Max

(Note 5)

0.015 %

40 nV/

Units

Simplified Schematic

20007603

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Typical Performance Characteristics Unless otherwise specified, V

T

LM321

= 25˚C.

A

Small Signal Pulse Response Large Signal Pulse Response

20007604

Supply Current vs. Supply Voltage Sinking Current vs. Output Voltage

= +5V, single supply,

S

20007605

20007612 20007613

Source Current vs. Output Voltage Open Loop Frequency Response

20007617 20007614

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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 V
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 V

(at 25˚C).An input clamp diode

DC

with a resistor to the IC input terminal can be used.
To reduce the power supply drain, the amplifier has a classA

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. Valuesof 50pF

DC

LM321

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 V

to 30 VDC.

DC

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.

Typical Applications

Non-Inverting DC Gain (0V Input = 0V Output)

20007606

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Typical Applications (Continued)

LM321

Amplitude Modulator Circuit

Power Amplifier LED Driver

20007602

DC Summing Amplifier

(V

≥ 0VDCand VO≥ VDC)

IN’s

Where: V0=V1+V2-V3-V4,(V1+V2)≥(V3+V4) to keep V

20007607

>

0V

O

DC

V0=0VDCfor VIN=0VDC,AV=10

Fixed Current Sources Lamp Driver

20007609

20007608

20007611

20007610

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SOT23-5 Tape and Reel Specification

TAPE DIMENSIONS

LM321

20007615

±

8mm 0.130

(3.3)

Tape Size DIM A DIM Ao DIM B DIM Bo DIM F DIM Ko DIM P1 DIM W

0.124
(3.15)

0.130
(3.3)

0.126
(3.2)

0.138±0.002

±

0.05)

(3.5

0.055
(1.4

±

0.004

0.11)

0.157
(4)

0.315
(8

±

±

0.3)

0.012

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SOT23-5 Tape and Reel Specification (Continued)

LM321

REEL DIMENSIONS

8mm 7.00

330.00

Tape Size A B C D N W1 W2 W3

0.059

1.50

0.512

13.00

0.795

20.20

2.165

55.00

0.331 + 0.059/−0.000

8.40 + 1.50/−0.00

0.567

14.40

W1 + 0.078/−0.039

W1 + 2.00/−1.00

20007616

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Physical Dimensions inches (millimeters) unless otherwise noted

LM321 Low Power Single Op Amp

5-Pin SOT23

NS Package Number MF05A

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