LM148/LM248/LM348
Quad 741 Op Amps
LM149
Wide Band Decompensated (A
V (MIN)
= 5)
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
thermal coupling. The LM149 series has the same features
as the LM148 plus a gain bandwidth product of 4 MHz at a
gain of 5 or greater.
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
n
741 op amp operating characteristics
n
Class AB output stage -- no crossover distortion
n
Pin compatible with the LM124
n
Overload protection for inputs and outputs
n
Low supply current drain:
0.6 mA/Amplifier
n
Low input offset voltage:
1 mV
n
Low input offset current:
4 nA
n
Low input bias current
30 nA
n
High degree of isolation between amplifiers:
120 dB
n
Gain bandwidth product
n
LM148 (unity gain):
1.0 MHz
n
LM149 (A
V
5):
4 MHz
Schematic Diagram
DS007786-1
* 1 pF in the LM149
December 2000
LM148/LM149
Series
Quad
741
Op
Amp
2001 National Semiconductor Corporation
DS007786
www.national.com
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/LM149
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
d
at 25C) and
Thermal Resistance (
jA
), (Note 2)
Molded DIP (N) P
d
--
--
750 mW
jA
--
--
100C/W
Cavity DIP (J) P
d
1100 mW
800 mW
700 mW
JA
110C/W
110C/W
110C/W
Maximum Junction Temperature (T
jMAX
)
150C
110C
100C
Operating Temperature Range
-55C
T
A
+125C
-25C
T
A
+85C
0C
T
A
+70C
Storage Temperature Range
-65C to +150C
-65C to +150C
-65C to +150C
Lead Temperature (Soldering, 10 sec.) Ceramic
300C
300C
300C
Lead Temperature (Soldering, 10 sec.) Plastic
260C
Soldering Information
Dual-In-Line Package
Soldering (10 seconds)
260C
260C
260C
Small Outline Package
Vapor Phase (60 seconds)
215C
215C
215C
Infrared (15 seconds)
220C
220C
220C
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/LM149
LM248
LM348
Units
Min
Typ Max Min
Typ Max Min
Typ Max
Input Offset Voltage
T
A
= 25C, R
S
10 k
1.0
5.0
1.0
6.0
1.0
6.0
mV
Input Offset Current
T
A
= 25C
4
25
4
50
4
50
nA
Input Bias Current
T
A
= 25C
30
100
30
200
30
200
nA
Input Resistance
T
A
= 25C
0.8
2.5
0.8
2.5
0.8
2.5
M
Supply Current All Amplifiers
T
A
= 25C, V
S
=
15V
2.4
3.6
2.4
4.5
2.4
4.5
mA
Large Signal Voltage Gain
T
A
= 25C, V
S
=
15V
50
160
25
160
25
160
V/mV
V
OUT
=
10V, R
L
2 k
Amplifier to Amplifier
T
A
= 25C, f = 1 Hz to 20 kHz
Coupling
(Input Referred) See Crosstalk
-120
-120
-120
dB
Test Circuit
Small Signal Bandwidth
LM148 Series
1.0
1.0
1.0
MHz
T
A
= 25C
LM149 Series
4.0
4.0
4.0
MHz
Phase Margin
LM148 Series (A
V
= 1)
60
60
60
degrees
T
A
= 25C
LM149 Series (A
V
= 5)
60
60
60
degrees
Slew Rate
LM148 Series (A
V
= 1)
0.5
0.5
0.5
V/s
T
A
= 25C
LM149 Series (A
V
= 5)
2.0
2.0
2.0
V/s
Output Short Circuit Current
T
A
= 25C
25
25
25
mA
Input Offset Voltage
R
S
10 k
6.0
7.5
7.5
mV
Input Offset Current
75
125
100
nA
LM148/LM149/LM248/LM348
www.national.com
2
Electrical Characteristics
(Continued)
(Note 3)
Parameter
Conditions
LM148/LM149
LM248
LM348
Units
Min
Typ Max Min
Typ Max Min
Typ Max
Input Bias Current
325
500
400
nA
Large Signal Voltage Gain
V
S
=
15V, V
OUT
=
10V,
25
15
15
V/mV
R
L
>
2 k
Output Voltage Swing
V
S
=
15V, R
L
= 10 k
12
13
12
13
12
13
V
R
L
= 2 k
10
12
10
12
10
12
V
Input Voltage Range
V
S
=
15V
12
12
12
V
Common-Mode Rejection
R
S
10 k
70
90
70
90
70
90
dB
Ratio
Supply Voltage Rejection
R
S
10 k
,
5V
V
S
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 T
jMAX
,
jA
, and the ambient temperature,
T
A
. The maximum available power dissipation at any temperature is P
d
= (T
jMAX
- T
A
)/
jA
or the 25C P
dMAX
, whichever is less.
Note 3: These specifications apply for V
S
=
15V and over the absolute maximum operating temperature range (T
L
T
A
T
H
) unless otherwise noted.
Note 4: Refer to RETS 148X for LM148 military specifications and refer to RETS 149X for LM149 military specifications.
Note 5: Human body model, 1.5 k
in series with 100 pF.
Cross Talk Test Circuit
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
characteristics 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 LM149 series has the same characteristics as the
LM148 except it has been decompensated to provide a
wider bandwidth. As a result the part requires a minimum
gain of 5.
DS007786-6
DS007786-7
DS007786-43
V
S
=
15V
LM148/LM149/LM248/LM348
www.national.com
3
Typical Performance Characteristics
Supply Current
DS007786-23
Input Bias Current
DS007786-24
Voltage Swing
DS007786-25
Positive Current Limit
DS007786-26
Negative Current Limit
DS007786-27
Output Impedance
DS007786-28
Common-Mode Rejection
Ratio
DS007786-29
Open Loop Frequency
Response
DS007786-30
Bode Plot LM148
DS007786-31
LM148/LM149/LM248/LM348
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4
Typical Performance Characteristics
(Continued)
Bode Plot LM149
DS007786-32
Large Signal Pulse
Response (LM148)
DS007786-33
Large Signal Pulse
Response (LM149)
DS007786-34
Small Signal Pulse
Response (LM148)
DS007786-35
Small Signal Pulse
Response (LM149)
DS007786-36
Undistorted Output
Voltage Swing
DS007786-37
Gain Bandwidth
DS007786-38
Slew Rate
DS007786-39
Inverting Large Signal Pulse
Response (LM149)
DS007786-40
LM148/LM149/LM248/LM348
www.national.com
5
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