LM348N/NOPB - National Semiconductor

LM148/LM248/LM348

Quad 741 Op Amps

General Description

The LM148 series is a true quad 741. It consists of four

independent, high gain, internally compensated, low power

operational amplifiers which have been designed to provide

functional characteristics identical to those of the familiar

741 operational amplifier. In addition the total supply current

for all four amplifiers is comparable to the supply current of a

single 741 type op amp. Other features include input offset

currents and input bias current which are much less than

those of a standard 741. Also, excellent isolation between

amplifiers has been achieved by independently biasing each

amplifier and using layout techniques which minimize ther-

mal coupling.

The LM148 can be used anywhere multiple 741 or 1558 type

amplifiers are being used and in applications where amplifier

matching or high packing density is required. For lower

power refer to LF444.

Features

n741 op amp operating characteristics

nClass AB output stage — no crossover distortion

nPin compatible with the LM124

nOverload protection for inputs and outputs

nLow supply current drain: 0.6 mA/Amplifier

nLow input offset voltage: 1 mV

nLow input offset current: 4 nA

nLow input bias current 30 nA

nHigh degree of isolation between amplifiers: 120 dB

nGain bandwidth product

nLM148 (unity gain): 1.0 MHz

Schematic Diagram

00778601

* 1 pF in the LM149

November 2003

LM148/LM248/LM348 Series Quad 741 Op Amp

Absolute Maximum Ratings (Note 4)

If Military/Aerospace specified devices are required,

please contact the National Semiconductor Sales Office/

Distributors for availability and specifications.

LM148 LM248 LM348

Supply Voltage ±22V ±18V ±18V

Differential Input Voltage ±44V ±36V ±36V

Output Short Circuit Duration (Note 1) Continuous Continuous Continuous

Power Dissipation (P

at 25˚C) and

Thermal Resistance (θ

), (Note 2)

Molded DIP (N) P

— — 750 mW

— — 100˚C/W

Cavity DIP (J) P

1100 mW 800 mW 700 mW

110˚C/W 110˚C/W 110˚C/W

Maximum Junction Temperature (T

jMAX

) 150˚C 110˚C 100˚C

Operating Temperature Range −55˚C ≤T

≤+125˚C −25˚C ≤T

≤+85˚C 0˚C ≤T

≤+70˚C

Storage Temperature Range −65˚C to +150˚C −65˚C to +150˚C −65˚C to +150˚C

Lead Temperature (Soldering, 10 sec.) Ceramic 300˚C 300˚C 300˚C

Lead Temperature (Soldering, 10 sec.) Plastic 260˚C

Soldering Information

Dual-In-Line Package

Soldering (10 seconds) 260˚C 260˚C 260˚C

Small Outline Package

Vapor Phase (60 seconds) 215˚C 215˚C 215˚C

Infrared (15 seconds) 220˚C 220˚C 220˚C

See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of soldering surface

mount

devices.

ESD tolerance (Note 5) 500V 500V 500V

Electrical Characteristics

(Note 3)

Parameter Conditions LM148 LM248 LM348 Units

Min Typ Max Min Typ Max Min Typ Max

Input Offset Voltage T

= 25˚C, R

≤10 kΩ1.0 5.0 1.0 6.0 1.0 6.0 mV

Input Offset Current T

= 25˚C 4 25 4 50 4 50 nA

Input Bias Current T

= 25˚C 30 100 30 200 30 200 nA

Input Resistance T

= 25˚C 0.8 2.5 0.8 2.5 0.8 2.5 MΩ

Supply Current All Amplifiers T

= 25˚C, V

=±15V 2.4 3.6 2.4 4.5 2.4 4.5 mA

Large Signal Voltage Gain T

= 25˚C, V

=±15V 50 160 25 160 25 160 V/mV

OUT

=±10V, R

≥2kΩ

Amplifier to Amplifier T

= 25˚C,f=1Hzto20kHz

Coupling (Input Referred) See Crosstalk −120 −120 −120 dB

Test Circuit

Small Signal Bandwidth T

= 25˚C,

LM148 Series

1.0 1.0 1.0 MHz

Phase Margin T

= 25˚C,

LM148 Series (A

=1)

60 60 60 degrees

Slew Rate T

= 25˚C,

LM148 Series (A

=1)

0.5 0.5 0.5 V/µs

Output Short Circuit Current T

= 25˚C 25 25 25 mA

Input Offset Voltage R

≤10 kΩ6.0 7.5 7.5 mV

Input Offset Current 75 125 100 nA

LM148/LM248/LM348

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Electrical Characteristics (Continued)

(Note 3)

Parameter Conditions LM148 LM248 LM348 Units

Min Typ Max Min Typ Max Min Typ Max

Input Bias Current 325 500 400 nA

Large Signal Voltage Gain V

=±15V, V

OUT

=±10V, 25 15 15 V/mV

>2kΩ

Output Voltage Swing V

=±15V, R

=10kΩ±12 ±13 ±12 ±13 ±12 ±13 V

=2kΩ±10 ±12 ±10 ±12 ±10 ±12 V

Input Voltage Range V

=±15V ±12 ±12 ±12 V

Common-Mode Rejection R

≤10 kΩ70 90 70 90 70 90 dB

Ratio

Supply Voltage Rejection R

≤10 kΩ,±5V ≤V

≤±15V 77 96 77 96 77 96 dB

Note 1: Any of the amplifier outputs can be shorted to ground indefinitely; however, more than one should not be simultaneously shorted as the maximum junction

temperature will be exceeded.

Note 2: The maximum power dissipation for these devices must be derated at elevated temperatures and is dicated by TJMAX,θJA, and the ambient temperature,

TA. The maximum available power dissipation at any temperature is Pd=(T

JMAX −T

A)/θJA or the 25˚C PDMAX, whichever is less.

Note 3: These specifications apply for VS=±15V and over the absolute maximum operating temperature range (TL≤TA≤TH) unless otherwise noted.

Note 4: Refer to RETS 148X for LM148 military specifications.

Note 5: Human body model, 1.5 kΩin series with 100 pF.

Cross Talk Test Circuit V

=±15V

00778606 00778607

00778643

LM148/LM248/LM348

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Typical Performance Characteristics

Supply Current Input Bias Current

00778623 00778624

Voltage Swing Positive Current Limit

00778625 00778626

Negative Current Limit Output Impedance

00778627

00778628

LM148/LM248/LM348

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Typical Performance Characteristics (Continued)

Common-Mode Rejection Ratio Open Loop Frequency Response

00778629 00778630

Bode Plot LM148 Large Signal Pulse Response (LM148)

00778631 00778633

Small Signal Pulse Response (LM148) Undistorted Output Voltage Swing

00778635 00778637

LM148/LM248/LM348

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Typical Performance Characteristics (Continued)

Gain Bandwidth Slew Rate

00778638 00778639

Inverting Large Signal Pulse Response (LM148) Input Noise Voltage and Noise Current

00778641 00778642

Positive Common-Mode Input Voltage Limit Negative Common-Mode Input Voltage Limit

00778643

00778605

LM148/LM248/LM348

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Application Hints

The LM148 series are quad low power 741 op amps. In the

proliferation of quad op amps, these are the first to offer the

convenience of familiar, easy to use operating characteris-

tics of the 741 op amp. In those applications where 741 op

amps have been employed, the LM148 series op amps can

be employed directly with no change in circuit performance.

The package pin-outs are such that the inverting input of

each amplifier is adjacent to its output. In addition, the

amplifier outputs are located in the corners of the package

which simplifies PC board layout and minimizes package

related capacitive coupling between amplifiers.

The input characteristics of these amplifiers allow differential

input voltages which can exceed the supply voltages. In

addition, if either of the input voltages is within the operating

common-mode range, the phase of the output remains cor-

rect. If the negative limit of the operating common-mode

range is exceeded at both inputs, the output voltage will be

positive. For input voltages which greatly exceed the maxi-

mum supply voltages, either differentially or common-mode,

resistors should be placed in series with the inputs to limit

the current.

Like the LM741, these amplifiers can easily drive a 100 pF

capacitive load throughout the entire dynamic output voltage

and current range. However, if very large capacitive loads

must be driven by a non-inverting unity gain amplifier, a

resistor should be placed between the output (and feedback

connection) and the capacitance to reduce the phase shift

resulting from the capacitive loading.

The output current of each amplifier in the package is limited.

Short circuits from an output to either ground or the power

supplies will not destroy the unit. However, if multiple output

shorts occur simultaneously, the time duration should be

short to prevent the unit from being destroyed as a result of

excessive power dissipation in the IC chip.

As with most amplifiers, care should be taken lead dress,

component placement and supply decoupling in order to

ensure stability. For example, resistors from the output to an

input should be placed with the body close to the input to

minimize “pickup” and maximize the frequency of the feed-

back pole which capacitance from the input to ground cre-

ates.

A feedback pole is created when the feedback around any

amplifier is resistive. The parallel resistance and capacitance

from the input of the device (usually the inverting input) to AC

ground set the frequency of the pole. In many instances the

frequency of this pole is much greater than the expected 3

dB frequency of the closed loop gain and consequently there

is negligible effect on stability margin. However, if the feed-

back pole is less than approximately six times the expected

3 dB frequency a lead capacitor should be placed from the

output to the input of the op amp. The value of the added

capacitor should be such that the RC time constant of this

capacitor and the resistance it parallels is greater than or

equal to the original feedback pole time constant.

Typical Applications—LM148

One Decade Low Distortion Sinewave Generator

00778608

fMAX = 5 kHz, THD ≤0.03%

R1 = 100k pot. C1 = 0.0047 µF, C2 = 0.01 µF, C3 = 0.1 µF, R2 = R6 = R7 = 1M,

R3 = 5.1k, R4 = 12Ω,R5=240Ω, Q = NS5102, D1 = 1N914, D2 = 3.6V avalanche

diode (ex. LM103), VS=±15V

A simpler version with some distortion degradation at high frequencies can be made by using A1 as a simple inverting amplifier, and by putting back to back

zeners in the feedback loop of A3.

LM148/LM248/LM348

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Typical Applications—LM148 (Continued)

Low Cost Instrumentation Amplifier

00778609

VS=±15V

R = R2, trim R2 to boost CMRR

Low Drift Peak Detector with Bias Current Compensation

00778610

Adjust R for minimum drift

D3 low leakage diode

D1 added to improve speed

VS=±15V

LM148/LM248/LM348

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Typical Applications—LM148 (Continued)

Universal State-Variable Filter

00778611

Tune Q through R0,

For predictable results: fOQ≤4x10

Use Band Pass output to tune for Q

LM148/LM248/LM348

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Typical Applications—LM148 (Continued)

A 1 kHz 4 Pole Butterworth

00778612

Use general equations, and tune each section separately

Q1stSECTION = 0.541, Q2ndSECTION = 1.306

The response should have 0 dB peaking

A 3 Amplifier Bi-Quad Notch Filter

00778613

Ex: fNOTCH = 3 kHz, Q = 5, R1 = 270k, R2 = R3 = 20k, R4 = 27k, R5 = 20k, R6 = R8 = 10k, R7 = 100k, C1 = C2 = 0.001 µF

Better noise performance than the state-space approach.

LM148/LM248/LM348

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Typical Applications—LM148 (Continued)

A 4th Order 1 kHz Elliptic Filter (4 Poles, 4 Zeros)

00778614

R1C1 = R2C2 = t

R'1C'1 = R'2C'2 = t'

fC= 1 kHz, fS= 2 kHz, fp= 0.543, fZ= 2.14, Q = 0.841, f' P= 0.987, f' Z= 4.92, Q' = 4.403, normalized to ripple BW

Use the BP outputs to tune Q, Q', tune the 2 sections separately

R1 = R2 = 92.6k, R3 = R4 = R5 = 100k, R6 = 10k, R0 = 107.8k, RL= 100k, RH= 155.1k,

R'1 = R'2 = 50.9k, R'4 = R'5 = 100k, R'6 = 10k, R'0 = 5.78k, R'L= 100k, R'H= 248.12k, R'f = 100k. All capacitors are 0.001 µF.

Lowpass Response

00778615

LM148/LM248/LM348

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Typical Simulation

LM148, LM741 Macromodel for Computer Simulation

00778621

For more details, see IEEE Journal of Solid-State Circuits, Vol. SC-9, No. 6, December 1974

Note 6: o1 = 112IS=8x10

−16

Note 7: o2 = 144*C2=6pFforLM149

00778622

LM148/LM248/LM348

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Connection Diagram

00778602

Top View

Order Number LM148J, LM148J/883, LM248J, LM348M, or LM348N

See NS Package Number J14A, M14A or N14A

LM148J is available per JM38510/11001

LM148/LM248/LM348

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Physical Dimensions inches (millimeters)

unless otherwise noted

Ceramic Dual-In-Line Package (J)

Order Number LM148J, LM148J/883, LM248J

NS Package Number J14A

S.O. Package (M)

Order Number LM348M or LM348MX

NS Package Number M14A

LM148/LM248/LM348

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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

Molded Dual-In-Line Package (N)

Order Number LM348N

NS Package Number N14A

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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.

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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.

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LM148/LM248/LM348 Series Quad 741 Op Amp

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.