ETC LM308A/D

LM308A
Precision Operational
Amplifier
The LM308A operational amplifier provides high input impedance,
low input offset and temperature drift, and low noise. These
characteristics are made possible by use of a special Super Beta
processing technology. This amplifier is particularly useful for
applications where high accuracy and low drift performance are
essential. In addition high speed performance may be improved by
employing feedforward compensation techniques to maximize slew
rate without compromising other performance criteria.
The LM308A offers extremely low input offset voltage and drift
specifications allowing usage in even the most critical applications
without external offset nulling.
• Operation from a Wide Range of Power Supply Voltages
• Low Input Bias and Offset Currents
• Low Input Offset Voltage and Guaranteed Offset Voltage Drift
Performance
• High Input Impedance
http://onsemi.com
MARKING
DIAGRAMS
8
PDIP–8
N SUFFIX
CASE 626
8
LM308AN
AWL
YYWW
1
1
8
SO–8
D SUFFIX
CASE 751
8
1
LM308
ALYWA
1
Frequency Compensation
R2
Inverting
Input
Noninverting
Input
R1
Output
R3
+
Compen A
Cf
A
= Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
R2
Compen B
Cf ≥ 30
1
1+
Inverting
Input
Noninverting
Input
R1
Output
R3
+
Compen B
100pF
PIN CONNECTIONS
R2
R1
Standard Compensation
Modified Compensation
Compen A
1
2
Inputs
Input
5.0pF
10k
Input
10
k
+
500pF
CompenA
RS > 10k
100k
C2*
0.01µF
Output
CompenB
3.0k
10pF
VEE
10pF
+
 Semiconductor Components Industries, LLC, 2000
April, 2000 – Rev. 1
4
Compen B
7
VCC
6
Output
5
NC
Compen B
3.0k
CompenA
CL
75pF
to
0.01µF
10pF
*C2 >
Standard Feedforward
Compensation
+
8
(Top View)
500
500pF
3
–
5 x 105
pF
R2
Feedforward Compensations for
Decoupling Load Capacitance
1
ORDERING INFORMATION
Device
Package
Shipping
LM308AN
PDIP–8
50 Units/Rail
LM308AD
SO–8
98 Units/Rail
LM308ADR2
SO–8
2500 Tape & Reel
Publication Order Number:
LM308A/D
LM308A
MAXIMUM RATINGS (TA = +25°C, unless otherwise noted.)
Symbol
Value
Unit
Power Supply Voltage
VCC, VEE
±18
Vdc
Input Voltage (Note 1.)
VI
±15
V
Input Differential Current (Note 2.)
IID
±10
mA
Output Short Circuit Duration
tSC
Indefinite
–
Operating Ambient Temperature Range
TA
0 to +70
°C
Storage Temperature Range
Tstg
–65 to +150
°C
Junction Temperature
TJ
+150
°C
Rating
1. For supply voltages less than ±15 V, the maximum input voltage is equal to the supply voltage.
2. The inputs are shunted with back–to–back diodes for overvoltage protection. Therefore, excessive current will flow if a differential input
voltage in excess of 1.0 V is applied between the inputs, unless some limiting resistance is used.
ELECTRICAL CHARACTERISTICS (Unless otherwise noted these specifications apply for supply voltages of +5.0 V ≤ VCC ≤
+15 V and –5.0 V ≥ VEE ≥ –15 V, TA = +25°C.)
Symbol
Min
Typ
Max
Unit
Input Offset Voltage
VIO
–
0.3
0.5
mV
Input Offset Current
IIO
–
0.2
1.0
nA
Input Bias Current
IIB
–
1.5
7.0
nA
Input Resistance
ri
10
40
–
MΩ
ICC, IEE
–
±0.3
±0.8
mA
AVOL
80
300
–
V/mV
VIO
–
–
0.73
mV
Characteristic
Power Supply Currents
(VCC = +15 V, VEE = –15 V)
Large Signal Voltage Gain
(VCC = +15 V, VEE = –15 V, VO = ±10 V, RL ≥ 10 kΩ)
The following specifications apply over the operating temperature range.
Input Offset Voltage
Input Offset Current
Average Temperature Coefficient of Input Offset Voltage
IIO
–
–
1.5
nA
∆VIO/∆T
–
1.0
5.0
µV/°C
∆IIO/∆T
–
2.0
10
pA/°C
IIB
–
–
10
nA
AVOL
60
–
–
V/mV
VICR
±14
–
–
V
CMR
96
110
–
dB
PSR
96
110
–
dB
VOR
±13
±14
–
V
TA (min) ≤ TA ≤ TA (max)
Average Temperature Coefficient of Input Offset Current
Input Bias Current
Large Signal Voltage Gain
(VCC +15 V, VEE = –15 V, VO = ±10 V, RL ≥ 10 kΩ)
Input Voltage Range
(VCC = +15 V, VEE = –15 V)
Common Mode Rejection
(RS ≤ 50 kΩ)
Supply Voltage Rejection
(RS ≤ 50 kΩ)
Output Voltage Range
(VCC = +15 V, VEE = –15 V, RL = 10 kΩ)
http://onsemi.com
2
0.25
1.8
1.6
0.20
1.4
IIO
1.2
1.0
0.15
IIB
0.8
0.10
0.6
0.4
0.05
0.2
0
-60 -40
-20
0
20
40
60
80
T, TEMPERATURE (°C)
100
0
120 140
EQUIVALENT INPUT OFFSET VOLTAGE (mV)
2.0
I IO, INPUT OFFSET CURRENT (nA)
I IB , INPUT BIAS CURRENT (nA)
LM308A
100
10
1.0
0.1
100 k
Figure 1. Input Bias and Input Offset Currents
IEE , SUPPLY CURRENTS ( µ A)
TA = 0°C
+25°C
-55°C
+70°C
+125°C
80
0
5.0
10
15
=
CF = 0
f = 100 Hz
90
400
TA = -55°C
0°C
300
+25°C
200
+70°C
+125°C
100
0
20
0
5.0
15
10
VCC =  VEE, SUPPLY VOLTAGES (V)
VCC =  VEE, SUPPLY VOLTAGES (V)
Figure 3. Voltage Gain versus Supply Voltages
Figure 4. Power Supply Currents versus
Power Supply Voltages
140
VOR, OUTPUT VOLTAGE RANGE (± Vp-p)
100
80
CF = 3.0 pF
60
40
CF = 30 pF
20
0
-20
1.0
20
20
120
AVOL , VOLTAGE GAIN (dB)
500
I CC
AVOL , VOLTAGE GAIN (dB)
120
100
100 M
Figure 2. Maximum Equivalent Input Offset
Voltage Error versus Input Resistance
130
110
1.0 M
10 M
ri, INPUT RESISTANCE (Ω)
CF = 100 pF
10
100
1.0 k
10 k
100 k 1.0 M
10 M
100 M
VCC = +15 V
VEE = -15 V
TA = +25°C
16
12
8.0
CF = 3.0 pF
4.0
CF = 30 pF
0
1.0 k
f, FREQUENCY (Hz)
10 k
100 k
f, FREQUENCY (Hz)
Figure 5. Open Loop Frequency Response
Figure 6. Large Signal Frequency Response
http://onsemi.com
3
1.0 M
LM308A
SUGGESTED DESIGN APPLICATIONS
INPUT GUARDING
input pins are adjacent to pins that are at supply potentials.
This leakage can be significantly reduced by using guarding
to lower the voltage difference between the inputs and
adjacent metal runs. The guard, which is a conductive ring
surrounding the inputs, is connected to a low–impedance
point that is at approximately the same voltage as the inputs.
Leakage currents from high voltage pins are then absorbed
by the guard.
Special care must be taken in the assembly of printed
circuit boards to take full advantage of the low input currents
of the LM308A amplifier. Boards must be thoroughly
cleaned with alcohol and blown dry with compressed air.
After cleaning, the boards should be coated with epoxy or
silicone rubber to prevent contamination.
Even with properly cleaned and coated boards, leakage
currents may cause trouble at +125°C, particularly since the
C5 (2)
RS
Input
150k
R1
R4
0.002µF
0.002
µF
R2
1M
LM308A
150pF
1
6
2
3
1.0M
Compen B
300pF
VCC
Output
1.0M
Input
LM101A(3)
or equiv
Q1
Sample
(1) Power Bandwidth: 250 kHz
Small Signal Bandwidth:
3.5 MHz
Slew Rate: 10 V/µs
(2) C5 =
6 X 10-8
R1
1.0µF (1)
30pF
(1) Teflon, Polyethylene or Polycarbonate
Dielectric Capacitor
Figure 7. Fast (1) Summing Amplifier with
Low Input Current
Figure 8. Sample and Hold
Inverting Amplifier
Input
Output
Q2
(3) In addition to increasing speed,
the LM101A raises high and low
frequency gain, increases output
drive capability and eliminates
thermal feedback.
R1
Follower
R2
Noninverting Amplifier
R2
R3 (1)
R3 (1)
Output
Output
Input
Output
R1
R3 (1)
C1
C1
(1) Used to compensate for large source resistances.
Figure 9. Connection of Input Guards
http://onsemi.com
4
C1
Input
R1 R2
Note:
must be an impedance.
R1 +R2
LM308A
Representative Circuit Schematic
Compensation A
Compensation B
3.5k
5.6k
VCC
7.5k
15pF
17.4k
17.4k
1.0k
1.4k
7.5k
200
7.0k
1.0k
Inputs 2.0k
VCC
65
1.0k
Output
150
VEE
80k
2.0k
20k
362
10k
1.2k
50k
VEE
http://onsemi.com
5
LM308A
PACKAGE DIMENSIONS
PDIP–8
N SUFFIX
CASE 626–05
ISSUE K
8
NOTES:
1. DIMENSION L TO CENTER OF LEAD WHEN
FORMED PARALLEL.
2. PACKAGE CONTOUR OPTIONAL (ROUND OR
SQUARE CORNERS).
3. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
5
–B–
1
4
DIM
A
B
C
D
F
G
H
J
K
L
M
N
F
–A–
NOTE 2
L
C
J
–T–
MILLIMETERS
MIN
MAX
9.40
10.16
6.10
6.60
3.94
4.45
0.38
0.51
1.02
1.78
2.54 BSC
0.76
1.27
0.20
0.30
2.92
3.43
7.62 BSC
--10
0.76
1.01
INCHES
MIN
MAX
0.370
0.400
0.240
0.260
0.155
0.175
0.015
0.020
0.040
0.070
0.100 BSC
0.030
0.050
0.008
0.012
0.115
0.135
0.300 BSC
--10
0.030
0.040
N
SEATING
PLANE
D
M
K
G
H
0.13 (0.005)
M
T A
M
B
M
SO–8
D SUFFIX
CASE 751–06
ISSUE T
D
A
8
E
5
0.25
H
1
M
B
M
4
h
B
e
X 45 A
C
SEATING
PLANE
L
0.10
A1
NOTES:
1. DIMENSIONING AND TOLERANCING PER ASME
Y14.5M, 1994.
2. DIMENSIONS ARE IN MILLIMETER.
3. DIMENSION D AND E DO NOT INCLUDE MOLD
PROTRUSION.
4. MAXIMUM MOLD PROTRUSION 0.15 PER SIDE.
5. DIMENSION B DOES NOT INCLUDE DAMBAR
PROTRUSION. ALLOWABLE DAMBAR
PROTRUSION SHALL BE 0.127 TOTAL IN EXCESS
OF THE B DIMENSION AT MAXIMUM MATERIAL
CONDITION.
C
B
0.25
M
C B
S
A
S
http://onsemi.com
6
DIM
A
A1
B
C
D
E
e
H
h
L
MILLIMETERS
MIN
MAX
1.35
1.75
0.10
0.25
0.35
0.49
0.19
0.25
4.80
5.00
3.80
4.00
1.27 BSC
5.80
6.20
0.25
0.50
0.40
1.25
0
7
LM308A
Notes
http://onsemi.com
7
LM308A
ON Semiconductor and
are trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes
without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular
purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability,
including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or
specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be
validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others.
SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or
death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold
SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable
attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim
alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer.
PUBLICATION ORDERING INFORMATION
NORTH AMERICA Literature Fulfillment:
Literature Distribution Center for ON Semiconductor
P.O. Box 5163, Denver, Colorado 80217 USA
Phone: 303–675–2175 or 800–344–3860 Toll Free USA/Canada
Fax: 303–675–2176 or 800–344–3867 Toll Free USA/Canada
Email: [email protected]
Fax Response Line: 303–675–2167 or 800–344–3810 Toll Free USA/Canada
N. American Technical Support: 800–282–9855 Toll Free USA/Canada
EUROPE: LDC for ON Semiconductor – European Support
German Phone: (+1) 303–308–7140 (M–F 1:00pm to 5:00pm Munich Time)
Email: ONlit–[email protected]
French Phone: (+1) 303–308–7141 (M–F 1:00pm to 5:00pm Toulouse Time)
Email: ONlit–[email protected]
English Phone: (+1) 303–308–7142 (M–F 12:00pm to 5:00pm UK Time)
Email: [email protected]
EUROPEAN TOLL–FREE ACCESS*: 00–800–4422–3781
*Available from Germany, France, Italy, England, Ireland
CENTRAL/SOUTH AMERICA:
Spanish Phone: 303–308–7143 (Mon–Fri 8:00am to 5:00pm MST)
Email: ONlit–[email protected]
ASIA/PACIFIC: LDC for ON Semiconductor – Asia Support
Phone: 303–675–2121 (Tue–Fri 9:00am to 1:00pm, Hong Kong Time)
Toll Free from Hong Kong & Singapore:
001–800–4422–3781
Email: ONlit–[email protected]
JAPAN: ON Semiconductor, Japan Customer Focus Center
4–32–1 Nishi–Gotanda, Shinagawa–ku, Tokyo, Japan 141–0031
Phone: 81–3–5740–2745
Email: [email protected]
ON Semiconductor Website: http://onsemi.com
For additional information, please contact your local
Sales Representative.
http://onsemi.com
8
LM308A/D