LM108A/LM308A/LM108/LM308
a LM108A/LM308A
( y | IN LM108/LM308
TEC
HNOLOGY "Operational Amplifiers
FEATURES DESCRIPTION
m Guaranteed 200pA max. input offset current The LM108 series of precision operational amplifiers
m Guaranteed 2nA max. input bias current are particularly well-suited for high source impedance
m Guaranteed 600uA max. supply current applications requiring low offset and bias currents as
= Guaranteed 0.5mV max. offset voltage well as low power dissipation. Unlike FET input ampli-
m Guaranteed 5uV/°C max. drift fiers, the offset and bias currents of the LM108 do not
= Wide supply voltage range: + 2V to + 18V change significantly with temperature variations. Ad-
vanced design, processing and testing techniques
make Linear's LM108 a superior choice over previous
APPLICATIONS devices.
= Integrators A photodiode sensor application is shown below. For 2 |
ue Transducer amplifiers applications requiring higher performance, see the
= Analog memories LT1008, and LT1012.
m Light meters
Amplifier For Photodiode Sensor input Currents
RI 2.0
5M
1% 1.5
AAA
OO +
nn o
Si
—
on
INPUT CURRENT (nA)
©
е ©
a
©
OUTPUT
OFFSET
Vour = 10V/uA
©
o
on
R2
oM
1%
0
-55-35-15 5 25 45 65 85 105 125
TEMPERATURE (°C)
LY LINEAR 2.303
LM108A/LM308A
LM108/LM308
Hf 4
ABSOLUTE MAXIMUM RATINGS — PACKAGE/ORDER INFORMATION
Supply Voltage
LM108A/LM108 .................... +20V
LM308A/LM308 .................... + 18V
Differential Input Current (Note 1)......... + 10mA
Input Voltage (Note 2). .................. + 15V
Output Short Circuit Duration. .......... Indefinite
Operating Temperature Range
LM108A/LM108 ............ —55°C to 125°C
LM308A/LM308 ................ 0°Cto 70°C
Storage Temperature Range
AliDevices................. —65°C to 150°C
Lead Temperature (Soldering, 10 sec.)...... 300°C
ove ORDER PART NO.
. LM108AH
LM108H
- LM308AH
LM308H —
METAL CAN H PACKAGE
TOP VIEW
COMP1 1 8 COMP2
IN 2 7 V+ LM308ANS
+IN 3 6 OUT LM308N8
V- 4 5 NC o
PLASTIC DIP N8 PACKAGE
ELECTRICAL CHARACTERISTICS +5\ < V, < + 20V and —55% < T, < 125%, unless otherwise noted.
ВЕ LM108A LM108
SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
Vos Input Offset Voltage Ta = 25°C 0.3 0.5 0.7 2.0 my
© 1.0 3.0 mV
AV Average Temperature Coefficient
ATemp of Input Offset Voltage © 1.0 5.0 3.0 15 uV/°C
los Input Offset Current Ta = 25°C 005 0.2 0.05 0.2 nA
© 04 0.4 nA
Al Average Temperature Coefficient
ATemp of input Offset Current o 0.5 2.5 0.5 2.5 рА/°С
В Input Bias Current Ta = 25°C 0.5 2.0 0.5 2.0 nA
© 3.0 3.0 nA
AvoL Large Signal Voltage Gain Ta = 25°C, Vs + 15V, 80 300 50 300 V/mV
Vour = + 10V, Rı > 10kQ e| 40 25 V/mV
CMRR Common Mode Rejection Ratio e| 9 110 85 100 dB
PSRR Power Supply Rejection Ratio ®| 9 110 80 96 dB
Input Voltage Range Vs = + 15V ® | + 13.5 + 13.5 У
Vout Output Voltage Swing Vs = + 15V Rı = 10k ®| +13 +14 13 +14 V
Ra Input Resistance Ta = 25°C (Note 3) 30 70 30 70 MQ
ls Supply Current Ta = 25°C 0.3 0.6 0.3 0.6 mA
Ta = 125°C 0.15 04 015 04 mA
_
2-304 ALY NEAR
ELECTRICAL CHARACTERISTICS +ôV < Y, + 15V and 0°C < Ta < 70°C, unless otherwise noted.
LM108A/LM308A
LM108/LM308
LM308A LM308
SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
Vos Input Offset Voltage Ta = 25°C 0.3 0.5 2.0 7.5 mV
e 0.73 10 mV
AVos verage Temperature Coefficient
ATemp o Input Offset Voltage e 2.0 5.0 6.0 30 uV/°C
los Input Offset Current Ta = 25°C 0.2 1.0 0.2 10 nA
e 1.5 1.5 nA
Al Average Temperature Coefficient
ATemp of Input Offset Current e 2.0 10 2.0 10 pA/°C
в input Bias Current Ta = 25°C 15 7.0 15 7.0 nA
e 10 10 nA
AvoL Large Signal Voitage Gain Ta = 25°C, Vg + 15V, 80 300 25 300 VimV
Vour = + 10V, R, = 10kQ e| 60 15 V/mV
CMRR Common Mode Rejection Ratio ®| 9 110 80 100 ds
PSRR Power Supply Rejection Ratio e; 9% 110 80 96 dB
Input Voltage Range Vs = + 15V e| +14 +14 V
Vout Output Voitage Swing Vs = + 15VR = 10kQ e| +13 +14 +13 +14 V
Rin input Resistance Ta = 25°C (Note 3) 10 40 10 40 MQ
ls Supply Current Ta = 25°C 0.3 0.8 0.3 0.8 mA
The @ denotes the specifications which apply over the full operating
temperature range.
For MIL-STD components, please refer to LTC 883 data sheet for test
listing and parameters.
Note 1: Differential input voltages greater than 1V will cause
excessive current to flow through the input protection diodes unless
current limiting resistance is used.
Note 2: For supply voltages less than + 15V, the maximum input
voltage is equal to the supply voltage.
Note 3: Guaranteed by design.
a M——.Ñ )DÑ Ñl T —T—Í ÑÑ w— TC LDT——o——;;];;;—;]T]]TD——L——— Ll. ——
TYPICAL APPLICATIONS
Standard Compensation Circuit
COMPENSATION CIRCUITS
Alternate* Frequency Compensation
Feedforward Compensation
ca
R1 R2 R1 R2
—V dh AA AAA
IN YY Y
—_ Vin
— Vout
— Vout
+ Vin A — + > + Vin ww -—— 4
‹ В1 Со - с:**
— %0— 5
C= + R2 T toe
Cc" * Со = 30 pF —
* * BANDWIDTH AND SLEW RATE ARE
* IMPROVES REJECTION OF POWER
PROPORTIONAL TO 1/C;
SUPPLY NOISE BY A FACTOR OF TEN.
** BANDWIDTH AND SLEW RATE ARE
PROPORTIONAL TO 1/Cs
LY LINEAR 2-305
LM108A/LM308A
LM108/LM308
TYPICAL PERFORMANCE CHARACTERISTICS
EQUIVALENT INPUT OFFSET VOLTAGE (mV)
VOLTAGE GAIN (dB)
VOLTAGE GAIN (dB)
Guaranteed Offset Error
100
Ta = 25°C
10
1.0
0.1
0.1 1.0 10 100
MATCHED SOURCE RESISTANCE (Mg)
Open Loop
Frequency Response
120
180
100 С, = 3 pF С, = 3pF
80 Cs = 100 pF 135
60
90
40
20 [GAIN — 45
PHASE ==
0 Cs = 100
= 30
-20 a
1 10 100 1k 10k 100k 1M 10M
FREQUENCY (Hz)
Voltage Gain
120
Ta = 25°C
110
Ta = —55°C
100 Ta = 125°C
90
5 10 15 20
SUPPLY VOLTAGE (+ V)
(sse15ap) 9Y1 3SYHd
1000
DRIFT ERROR (uV/°C)
OUTPUT SWING (+ V)
OUTPUT SWING (+ V)
Guaranteed Drift Error
100
1.0
0.1 1.0 10 100
MATCHED SOURCE RESISTANCE (M9)
Large Signal
Frequency Response
16
Ta = 25°C
Vs = + 15V
= 3 pF
—
nN
1k 10k 100k 1M
FREQUENCY (Hz)
Output Swing
—e Vg = + 15V
Ne
10
Y
LA
Zn — >
Th = me
Т, = —55°С-
gt
0 2 4 6 8
OUTPUT CURRENT ( + mA)
Input Noise Voltage
1000
E
=
2 100
cc
=
=
=
=
10
10 100 1K 10k 100k
FREQUENCY (Hz)
Voltage Follower
Pulse Response
=
«3
=
= OUTPUT
od
ul
ca
E
2
Ta = 25°C
Vg = +15V
Cy = 30 pF
—10
0 20 40 60 80 100 120 140 160
TIME (us)
Supply Current
600
500
el Ta = —55°C
= 400
e Ta = 25%
= 300
=—
= 5
E 200 Ta = 125°C
on
100
0
5 10 15 20
SUPPLY VOLTAGE (+ V)
2-306
Ly NA
LM108A/LM308A
LM108/LM308
TVPICAL PERFORMANCE CHARACTERISTICS
Closed Loop Output Impedance Power Supply Rejection
10° | 120 T
"a. Vg = oc
’ 100 , Ta = 25°C —
10° / 7 = Ns Ay = 1
aa у = =, |
m z2 4 A z 90 NN TIVE SUPPLY
Зоо) ANA \ E No 3 POSITIVE
= \ y t 60 —
q EN N us À `
= о Ау = 1, С, = 30 pF 2 N
E Ay = 1000, С; = OpF > AY
= — a
= / А, = 1000, Le = 30 pF & 20 |NEGATIVE SUPPLY e]
= | | mn ~
S40-! Ta = 25°C — | | Ne
Y lout = + IMA 0 | =—, = 30 pF ña
Vs = +15V == Cs = 100 pF
107? L.. Á —20 | L
10 100 1k 10k 100k 1M 10M 100 tk 10k 100k 1M 10M
FREQUENCY (Hz) FREQUENCY (Hz)
_ _ EE ;—]—o—;] zo
Low Drift Integrator With Reset Inverting Amplifier With High Input Resistance
R2 R1 R2 R3
2M 2M 505
1% 1% 1%
INPUT ——
; R4
RESET > 50k
1%
R2 > Rt
R2 >>R3
n, — R2(R3 + 4) — OUTPUT
' R1R3
OUTPUT M T 100 pF
* Q1 AND Q3 SHOULD NOT HAVE
INTERNAL GATE-PROTECTION DIODES.
LY LIN 2.307
LM108A/LM308A
LM108/LM308
EE
TYPICAL APPLICATIONS
Amplifier For Piezoelectric Transducers Amplifier For Bridge Transducers
a vt
OUTPUT
R3 ci
22M я (7 30 pF
c1 L 100k
10uF T 4 À
R2 100k 3
11M
€
RI <
wi
[C3 TRANSDUCER NY
52 TS R3
T 100k rm SM
= 102k
NA
Fast* Summing Amplifier
C5% =
li
Vi
Ry Bilateral Current Source
ANN
Rs IL
AN 1 [
INPUT
< 150k 0.002 uF 0.002 uF | — R3 Vin
IF 2 “TRIAS
| R3 = R4 + R5
: IM q OUTPUT
3 - > R3
de 1M
8
C2
Т 300 pF
À À * Power Bandwidth: 250 КН?
- - Small Signal Bandwidth: 3.5 MHz =
+ In addition to increasing speed, Slew Rate: 10V/uS
lout
the LM101A raises high and low 6x 1078 R4
frequency gain, increases output 1C5 = R 1M
drive capability and eliminates f 1%
thermal feedback.
R RA
Sample and Hold 100k e e 100K
vt 0.1% 0.1% 0.1% 0.1%
N DD” м лу AAA, AAA
iM
INPUT |
21. ^ 2
al œ — TD e =
SAMPLE Ñ— al 3 OUTPUT
ne OUTPUT 8 a3
C2 C
* Teflon, polyethylene or с1* T 100 pF 100 pF
polycarbonate dielectric 1 uF = = ,
capacitor. L - = R1=R4R2=R3
Worst case drift = — <4— —— ———— — Ri
less than 2.5 mV/sec. 30 pF INPUTS + АТН
R2
2.308 47 LINEAR
LM108A/LM308A
LM108/LM308
APPLICATIONS INFORMATION
Input guarding MN Input protection
Input guarding is used to reduce surface leakage. a Current is limited by R2 even when input is connected
Guarding both sides of the board is required. Bulk toa voltage source outside the common mode range. If
leakage reduction is less and depends on the guard one supply reverses, current is controlled by Ri.
ring width. COMPENSATION These resistors do not affect normal operation.
|
INPUT ANA
— OUTPUT
The guard ring is connected to a low impedance point
at same potential as the sensitive input leads. Connec-
tions for various op amp configurations are shown
below.
AT Re
INPUT —AAA VV
PA The input resistor controls the current when the input
exceeds the supply voltages, when the power for the
op amp is turned off, or when the output is shorted.
—- OUTPUT
— OUTPUT
INVERTING
Offset Voltage Test Circuit
R1
50k *
AAA
Y Y Y
— OUTPUT
+ 15V
m
7
2 R3
Im a В ` -
INPUT oO +
FOLLOWER
R2 | 2 $
AAA 1000* < — Vo
6
=
4 —
©
R3
50k* _45V * RESISTORS MUST HAVE
o NS LOW THERMOELECTRIC
Ao POTENTIAL
> OUTPUT A, = 1000
INPUT O í t THIS CIRCUIT IS ALSO USED AS THE BURN-IN
CONFIGURATION WITH SUPPLY VOLTAGES EQUAL
ТО = 20\, 1 = 3 = 10К, А2 = 2000, Ау= 100.
47 LINCAR 2-309
NON-INVERTING
LM108A/LM308A
LM108/LM308
SCHEMATIC DINGRAM
COMPENSATION COMPENSATION
8 7
20k 20k 10k 10k 12
2k 018
> 013 1
a7 09 ot 2 5.6k
08 1 90 6
| 014 015 017 — A AA—— OUTPUT
Qs e 5 К ] 016 J 240
é $ 019
— e a Ко N
027 .
023
+
INPUTS 03 Q25
2 940
3 ¢ AA 020
+ 20k
za
820
4 024
> 20k
ik 4
v o V-
PACKAGE DESCRIPTION
H Package N8 Package
Metal Can 8 Lead Plastic
0.370
— (0355 — =
0.060 50
0 040 MAX
0.005 MIN
0.145
0.115
; :
y
< Los +: 0.05 тур
3 ТУР 21 a
0 100 850 3029
TYP
NOTE DIMENSIONS IN INCHES UNLESS OTHERWISE NOTED.
“LEADS WITHIN 0 007 OF TRUE POSITION (TP) AT GALIGE PLANE.
T max Sa
150°C | 150°C/W | 45°C/W 100°C | 130°C/W
2-310 ALY LINEAR
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