LT1055/LT1056 - Precision, High Speed, JFET Input Operational Amplifiers

LT1055/LT1056
Precision, High Speed,
JFET Input Operational Amplifiers
FEATURES
DESCRIPTION
Guaranteed Offset Voltage: 150µV Max
–55°C to 125°C: 500µV Max
nn Guaranteed Drift: 4µV/°C Max
nn Guaranteed Bias Current
70°C: 150pA Max
125°C: 2.5nA Max
nn Guaranteed Slew Rate: 12V/µs Min
nn Available in 8-Pin PDIP and SO Packages
The LT®1055/LT1056 JFET input operational amplifiers
combine precision specifications with high speed performance.
nn
For the first time, 16V/µs slew rate and 6.5MHz gain
bandwidth product are simultaneously achieved with offset
voltage of typically 50µV, 1.2µV/°C drift, bias currents of
40pA at 70°C and 500pA at 125°C.
The 150µV maximum offset voltage specification is the
best available on any JFET input operational amplifier.
APPLICATIONS
The LT1055 and LT1056 are differentiated by their operating
currents. The lower power dissipation LT1055 achieves
lower bias and offset currents and offset voltage. The additional power dissipation of the LT1056 permits higher
slew rate, bandwidth and faster settling time with a slight
sacrifice in DC performance.
Precision, High Speed Instrumentation
nn Logarithmic Amplifiers
nn D/A Output Amplifiers
nn Photodiode Amplifiers
nn Voltage-to-Frequency Converters
nn Frequency-to-Voltage Converters
nn Fast, Precision Sample-and-Hold
nn
The voltage-to-frequency converter shown below is one
of the many applications which utilize both the precision
and high speed of the LT1055/LT1056.
For a JFET input op amp with 23V/µs guaranteed slew
rate, refer to the LT1022 data sheet.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
Distribution of Input Offset Voltage
(H Package)
1Hz to 10kHz Voltage-to-Frequency Converter
4.7k
3M
15V
140
0.001 (POLYSTYRENE)
75k
2
0.1µF
2N3906
3.3M
3
–
LT1056
+
33pF
6
1.5k
OUTPUT
1Hz TO 10kHz
0.005%
LINEARITY
4
–15V
LM329
–15V
100
50% TO ±60µV
80
60
40
0
THE LOW OFFSET VOLTAGE OF LT1056
CONTRIBUTES ONLY 0.1Hz OF ERROR
WHILE ITS HIGH SLEW RATE PERMITS
10kHz OPERATION.
VS = ±15V
TA = 25°C
634 UNITS TESTED
FROM THREE RUNS
20
0.1µF
= 1N4148
*1% FILM
22k
15V
7
NUMBER OF UNITS
0V TO 10V
INPUT
10kHz
TRIM
5k
120
–400
–200
200
400
0
INPUT OFFSET VOLTAGE (µV)
LT1055/56 TA02
LT1055/56 TA01
10556fd
For more information www.linear.com/LT1055
1
LT1055/LT1056
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Supply Voltage ........................................................±20V
Differential Input Voltage.........................................±40V
Input Voltage ...........................................................±20V
Output Short-Circuit Duration........................... Indefinite
Operating Temperature Range
LT1055AM/LT1055M/LT1056AM/
LT1056M (OBSOLETE)....................... –55°C to 125°C
LT1055AC/LT1055C/LT1056AC/
LT1056C................................................... 0°C to 70°C
Storage Temperature Range
All Devices.......................................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................... 300°C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
BAL 1
8
N/C
BAL 1
8
N/C
–IN 2
7
V+
–IN 2
7
V+
+IN 3
6
OUT
+IN 3
6
OUT
BAL
–
5
BAL
V
–
4
5
V
N8 PACKAGE
8-LEAD PDIP
TJMAX = 150°C, θJA = 130°C/W
4
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 130°C/W
TOP VIEW
NC
BALANCE 1
–IN 2
8
7
V+
6 OUT
5 BALANCE
4
V–
H PACKAGE
8-LEAD TO-5 METAL CAN
TJMAX = 150°C, θJA = 150°C/W, θJC = 45°C/W
+IN 3
OBSOLETE PACKAGE
Consider the N8 for Alternate Source
10556fd
2
For more information www.linear.com/LT1055
LT1055/LT1056
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1055CN8#PBF
LT1055CN8#TRPBF
LT1055CN8
8-Lead PDIP
0°C to 70°C
LT1056CN8#PBF
LT1056CN8#TRPBF
LT1056CN8
8-Lead PDIP
0°C to 70°C
LT1055S8#PBF
LT1055S8#TRPBF
1055
8-Lead Plastic SO
0°C to 70°C
LT1056S8#PBF
LT1056S8#TRPBF
1056
8-Lead Plastic SO
0°C to 70°C
LT1055ACH#PBF
LT1055ACH#TRPBF
LT1055ACH
8-Lead TO-5 Metal Can
0°C to 70°C
LT1055CH#PBF
LT1055CH#TRPBF
LT1055CH
8-Lead TO-5 Metal Can
0°C to 70°C
LT1055AMH#PBF
LT1055AMH#TRPBF
LT1055AMH
8-Lead TO-5 Metal Can
–55°C to 125°C
LT1055MH#PBF
LT1055MH#TRPBF
LT1055MH
8-Lead TO-5 Metal Can
–55°C to 125°C
LT1056ACH#PBF
LT1056ACH#TRPBF
LT1056ACH
8-Lead TO-5 Metal Can
0°C to 70°C
LT1056CH#PBF
LT1056CH#TRPBF
LT1056CH
8-Lead TO-5 Metal Can
0°C to 70°C
LT1056AMH#PBF
LT1056AMH#TRPBF
LT1056AMH
8-Lead TO-5 Metal Can
–55°C to 125°C
LT1056MH#PBF
LT1056MH#TRPBF
LT1056MH
8-Lead TO-5 Metal Can
–55°C to 125°C
OBSOLETE PACKAGE
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on nonstandard lead based finish parts.
For more information on lead free part markings, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
TA = 25°C. VS = ±15V, VCM = 0V unless otherwise noted.
LT1055AM/LT1056AM
LT1055AC/LT1056AC
SYMBOL PARAMETER
CONDITIONS
VOS
Input Offset Voltage (Note 2)
IOS
IB
TYP
MAX
TYP
MAX
UNITS
LT1055 H Package
LT1056 H Package
LT1055 N8 Package
LT1056 N8 Package
50
50
150
180
70
70
120
140
400
450
700
800
µV
µV
µV
µV
Input Offset Current
Fully Warmed Up
2
10
2
20
pA
Input Bias Current
Fully Warmed Up
VCM = 10V
±10
30
±50
130
±10
30
±50
150
pA
pA
Common Mode VCM = –11V to 8V
VCM = 8V to 11V
1012
1012
1011
4
1012
1012
1011
4
Ω
Ω
Ω
pF
Input Noise Voltage
0.1Hz to 10Hz
1.8
2.5
2.0
2.8
µVP-P
µVP-P
Input Noise Voltage Density
fO = 10Hz (Note 3)
fO = 1kHz (Note 4)
Input Resistance:Differential
Input Capacitance
en
MIN
LT1055M/LT1056M
LT1055CH/LT1056CH
LT1055CN8/LT1056CN8
LT1055
LT1056
In
Input Noise Current Density
fO = 10Hz, 1kHz (Note 5)
AVOL
Large-Signal Voltage Gain
VO = ±10V
RL = 2k
RL = 1k
Input Voltage Range
28
14
50
20
1.8
4
MIN
30
15
60
22
nV/√Hz
nV/√Hz
1.8
4
fA/√Hz
150
130
400
300
120
100
400
300
V/mV
V/mV
±11
±12
±11
±12
V
86
100
83
98
dB
CMRR
Common Mode Rejection Ratio
VCM = ±11V
PSRR
Power Supply Rejection Ratio
VS = ±10V to ±18V
90
106
88
104
dB
VOUT
Output Voltage Swing
RL = 2k
±12
±13.2
±12
±13.2
V
10556fd
For more information www.linear.com/LT1055
3
LT1055/LT1056
ELECTRICAL CHARACTERISTICS
TA = 25°C. VS = ±15V, VCM = 0V unless otherwise noted.t
LT1055AM/LT1056AM
LT1055AC/LT1056AC
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
SR
Slew Rate
LT1055
LT1056
10
12
13
16
GBW
Gain Bandwidth Product
f = 1MHz
LT1055
LT1056
5.0
6.5
IS
Supply Current
LT1055
LT1056
2.8
5.0
Offset Voltage Adjustment Range RPOT = 100k
MAX
LT1055M/LT1056M
LT1055CH/LT1056CH
LT1055CN8/LT1056CN8
TYP
7.5
9.0
12
14
V/µs
V/µs
4.5
5.5
MHz
MHz
4.0
6.5
2.8
5.0
±5
MAX
UNITS
MIN
4.0
7.0
±5
mA
mA
mV
The l denotes the specifications which apply over the temperature range 0°C ≤ TA ≤ 70°C. VS = ±15V, VCM = 0V unless otherwise noted.
LT1055AC
LT1056AC
MIN
LT1055CH/LT1056CH
LT1055CN8/LT1056CN8
SYMBOL PARAMETER
CONDITIONS
TYP
MAX
TYP
MAX
UNITS
VOS
Input Offset Voltage (Note 2)
LT1055 H Package
LT1056 H Package
LT1055 N8 Package
LT1056 N8 Package
l
l
l
l
100
100
330
360
140
140
250
280
750
800
1250
1350
µV
µV
µV
µV
Average Temperature
Coefficient of Input Offset
Voltage
H Package (Note 6)
N8 Package (Note 6)
l
l
1.2
4.0
1.6
3.0
8.0
12.0
µV/°C
µV/°C
IOS
Input Offset Current
Warmed Up
TA = 70°C
LT1055
LT1056
l
l
10
14
50
70
16
18
80
100
pA
pA
IB
Input Bias Current
Warmed Up
TA = 70°C
LT1055
LT1056
l
l
±30
±40
±150
±80
±40
±50
±200
±240
pA
pA
AVOL
Large-Signal Voltage Gain
VO = ±10V, RL = 2k
l
80
250
60
250
V/mV
CMRR
l
85
100
82
98
dB
PSRR
Common Mode Rejection Ratio VCM = ±10.5V
Power Supply Rejection Ratio
VS = ±10V to ±18V
l
89
105
87
103
dB
VOUT
Output Voltage Swing
l
±12
±13.1
±12
±13.1
V
RL = 2k
MIN
The l denotes the specifications which apply over the temperature range –55°C ≤ TA ≤ 125°C. VS = ±15V, VCM = 0V, unless otherwise noted.
LT1055AM
LT1056AM
SYMBOL PARAMETER
CONDITIONS
VOS
Input Offset Voltage (Note 2)
Average Temperature
Coefficient of Input Offset
Voltage
(Note 6)
IOS
Input Offset Current
Warmed Up
TA = 125°C
IB
Input Bias Current
Warmed Up
TA = 125°C
AVOL
Large-Signal Voltage Gain
VO = ±10V, RL = 2k
l
40
120
35
120
V/mV
CMRR
l
85
100
82
98
dB
PSRR
Common Mode Rejection Ratio VCM = ±10.5V
Power Supply Rejection Ratio
VS = ±10V to ±17V
l
88
104
86
102
dB
VOUT
Output Voltage Swing
l
±12
±12.9
±12
±12.9
RL = 2k
MIN
LT1055M
LT1056M
TYP
MAX
l
l
180
180
l
LT1055
LT1056
LT1055
LT1056
LT1055
LT1056
TYP
MAX
UNITS
500
550
250
250
1200
1250
µV
µV
1.3
4.0
1.8
8.0
µV/°C
l
l
0.20
0.25
1.2
1.5
0.25
0.30
1.8
2.4
nA
nA
l
l
±0.4
±0.5
±2.5
±3.0
±0.5
±0.6
±4.0
±5.0
nA
nA
MIN
V
10556fd
4
For more information www.linear.com/LT1055
LT1055/LT1056
ELECTRICAL CHARACTERISTICS
TA = 25°C. VS = ±15V, VCM = 0V unless otherwise noted.
LT1055CS8/LT1056CS8
SYMBOL PARAMETER
CONDITIONS
VOS
Input Offset Voltage (Note 2)
IOS
Input Offset Current
IB
Input Bias Current
Input Resistance
Differential
Common Mode
MIN
TYP
MAX
UNITS
500
1500
µV
Fully Warmed Up
5
30
pA
Fully Warmed Up
VCM = 10V
±30
30
±100
150
pA
pA
VCM = –11V to 8V
VCM = 8V to 11V
0.4
0.4
0.05
TΩ
TΩ
TΩ
4
pF
Input Capacitance
Input Noise Voltage
0.1Hz to 10Hz
Input Noise Voltage Density
fO = 10Hz (Note 4)
fO = 1kHz (Note 4)
35
15
70
22
nV/√Hz
nV/√Hz
in
Input Noise Current Density
fO = 10Hz, 1kHz (Note 5)
2.5
10
fA/√Hz
AVOL
Large-Signal Voltage Gain
VO = ±10V
en
LT1055
LT1056
2.5
3.5
RL = 2k
RL = 1k
Input Voltage Range
CMRR
Common Mode Rejection Ratio
VCM = ±11V
µVP-P
µVP-P
120
100
400
300
V/mV
V/mV
±11
±12
V
83
98
dB
PSRR
Power Supply Rejection Ratio
VS = ±10V to ±18V
88
104
dB
VOUT
Output Voltage Swing
RL = 2K
±12
±13.2
V
SR
Slew Rate
LT1055
LT1056
7.5
9.0
12
14
V/µs
V/µs
GBW
Gain Bandwidth Product
f = 1MHz
LT1055
LT1056
4.5
5.5
MHz
MHz
IS
Supply Current
LT1055
LT1056
2.8
5.0
Offset Voltage Adjustment Range
RPOT = 100k
4.0
7.0
±5
mA
mA
mV
The l denotes the specifications which apply over the temperature range 0°C ≤ TA ≤ 70°C. VS = ±15V, VCM = 0V unless otherwise noted.
LT1055CS8/LT1056CS8
SYMBOL PARAMETER
VOS
TYP
MAX
UNITS
Input Offset Voltage (Note 2)
CONDITIONS
l
MIN
800
2200
µV
Average Temperature Coefficient of Input Offset Voltage
l
4
15
µV/°C
IOS
Input Offset Current
Warmed Up, TA = 70°C
l
18
150
pA
IB
Input Bias Current
Warmed Up, TA = 70°C
l
±60
±400
pA
AVOL
Large-Signal Voltage Gain
VO = ±10V, RL = 2k
l
60
CMRR
Common Mode Rejection Ratio
VCM = ±10.5V
l
PSRR
Power Supply Rejection Ratio
VS = ±10V to ±18V
l
VOUT
Output Voltage Swing
RL = 2K
l
250
V/mV
82
98
dB
87
103
dB
±12
±13.1
V
10556fd
For more information www.linear.com/LT1055
5
LT1055/LT1056
ELECTRICAL CHARACTERISTICS
For MIL-STD components, please refer to LTC883 data sheet for test
listing and parameters.
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: Offset voltage is measured under two different conditions:
(a) approximately 0.5 seconds after application of power; (b) at TA = 25°C
only, with the chip heated to approximately 38°C for the LT1055 and to
45°C for the LT1056, to account for chip temperature rise when the device
is fully warmed up.
Note 3: 10Hz noise voltage density is sample tested on every lot of A
grades. Devices 100% tested at 10Hz are available on request.
Note 4: This parameter is tested on a sample basis only.
Note 5: Current noise is calculated from the formula: in = (2qlB)1/2, where
q = 1.6 • 10–19 coulomb. The noise of source resistors up to 1GΩ swamps
the contribution of current noise.
Note 6: Offset voltage drift with temperature is practically unchanged when
the offset voltage is trimmed to zero with a 100k potentiometer between
the balance terminals and the wiper tied to V+. Devices tested to tighter
drift specifications are available on request.
TYPICAL PERFORMANCE CHARACTERISTICS
BIAS OR OFFSET CURRENTS
MAY BE POSITIVE OR NEGATIVE
100
BIAS CURRENT
30
10
3
OFFSET CURRENT
0
25
75
100
50
AMBIENT TEMPERATURE (°C)
125
80
800
TA = 125°C
40
A
–40
B
–120
–15
B
TA = 125°C
A = POSITIVE INPUT CURRENT
B = NEGATIVE INPUT CURRENT
–5
0
5
10
–10
COMMON MODE INPUT VOLTAGE (V)
100
80
60
40
20
15
*DISTRIBUTION IN THE PLASTIC (N8) PACKAGE
IS SIGNIFICANTLY WIDER.
50% YIELD
TO ±140µV
80
60
40
20
–1200
0
–800 –600 –400 –200 0 200 400 600 800
INPUT OFFSET VOLTAGE (µV)
LT1055/56 G03
Long Term Drift of
Representative Units
100
50
VS = ±15V
TA = 25°C
80
60
LT1056CN8
40
LT1055CN8
LT1056 H PACKAGE
20
0
0
VS = ±15V
TA = 25°C
40
LT1055 H PACKAGE
0
–10 –8 –6 –4 –2 0 2
4 6 8 10
OFFSET VOLTAGE DRIFT WITH TEMPERATURE (µV/°C)
VS = ±15V
TA = 25°C
550 UNITS
TESTED FROM
120 TWO RUNS
(LT1056)
100
140
Warm-Up Drift
CHANGE IN OFFSET VOLTAGE (µV)
BATTERY VOLTAGE (V)
120
50% TO
±1.5µV/°C
–800
160
LT1055/56 G02
Distribution of Offset Voltage Drift
with Temperature (H Package)*
VS = ±15V
634 UNITS TESTED
FROM THREE RUNS
0
–400
TA = 70°C
–80
400
TA = 25°C
A
0
TA = 70°C
LT1055/56 G01
140
1200
VS = ±15V
WARMED UP
NUMBER OF INPUTS
300
120
OFFSET VOLTAGE CHANGE (µV)
VS = ±15V
VCM = 0V
WARMED UP
Distribution of Input Offset
Voltage (N8 Package)
INPUT BIAS CURRENT, TA = 125°C (pA)
INPUT BIAS AND OFFSET CURRENT (pA)
1000
Input Bias Current Over the
Common Mode Range
INPUT BIAS CURRENT, TA = 25°C, TA = 70°C (pA)
Input Bias and Offset Currents
vs Temperature
1
3
4
2
TIME AFTER POWER ON (MINUTES)
30
20
10
0
–10
–20
–30
–40
5
LT1055/56 G05
–50
0
1
3
2
TIME (MONTHS)
4
5
LT1055/56 GO6
LT1055/56 G04
10556fd
6
For more information www.linear.com/LT1055
LT1055/LT1056
TYPICAL PERFORMANCE CHARACTERISTICS
LT1056
LT1055
0
2
6
4
TIME (SECONDS)
8
10
Voltage Noise vs Frequency
100
7
70
PEAK-TO-PEAK
NOISE
5
3
50
30
fO = 10kHz
2
20
fO = 1kHz
1
10
20
30
50
60
40
CHIP TEMPERATURE (°C)
70
LT1055/56 GO7
1000
RMS NOISE VOLTAGE DENSITY (nV/√Hz)
0.1Hz TO 10Hz PEAK-TO-PEAK NOISE (µV/P-P)
Noise vs Chip Temperature
10
RMS NOISE VOLTAGE DENSITY (nV/√Hz)
NOISE VOLTAGE (1µV/DIVISION)
0.1Hz to 10Hz Noise
300
100
LT1056
1/f CORNER = 28HZ
30
10
10
80
VS = ±15V
TA = 25°C
LT1055
1/f CORNER
= 20HZ
1
3
10
100
30
FREQUENCY (Hz)
LT1055/56 G09
LT1055/56 G08
LT1055 Large-Signal Response
20mV/DIV
5V/DIV
Small-Signal Response
5V/DIV
LT1056 Large-Signal Response
1000
300
AV = 1, CL = 100pf, 0.5µs/DIV
AV = 1, CL = 100pf, 0.5µs/DIV
LT1055/56 G10
LT1055/56 G12
AV = 1, CL = 100pf, 0.2µs/DIV
LT1055/56 G11
VS = ±15V
TA = 25°C
18
12
LT1055
8
LT1056 GBW
SLEW RATE (V/µS)
24
Output Impedance vs Frequency
LT1056
LT1055 GBW
20
6
4
10
LT1056 SLEW
2
LT1055 SLEW
6
0
0.1
1
FREQUENCY (MHz)
10
LT1055/56 G13
0
100
10
30
VS = ±15V
fO = 1MHz FOR GBW
–25
25
75
TEMPERATURE (°C)
125
LT1055/56 G14
GAIN BANDWIDTH PRODUCT (MHz)
PEAK-TO-PEAK OUTPUT SWING (V)
30
Slew Rate, Gain Bandwidth vs
Temperature
OUTPUT IMPEDANCE (Ω)
Undistorted Output Swing vs
Frequency
VS = ±15V
TA = 25°C
AV = 100
LT1055
LT1056
10
AV = 10
LT1055
1
LT1056
LT1055
LT1056
AV = 1
0.1
1
10
100
FREQUENCY (kHz)
1000
LT1055/56 G15
10556fd
For more information www.linear.com/LT1055
7
LT1055/LT1056
TYPICAL PERFORMANCE CHARACTERISTICS
Gain, Phase Shift vs Frequency
VS = ±15V
TA = 25°C
20
40
GAIN (dB)
GAIN
LT1056
LT1055
0
20
1
10
100
1k 10k 100k 1M 10M 100M
FREQUENCY (Hz)
–10
4
2
FREQUENCY (MHz)
1
6
LT1055/56 G16
1mV
5mV 2mV
–5
–10
0.5mV
5mV
0
10mV
1mV 0.5mV
VS = ±15V
TA = 25°C
1
0
2
Common Mode Range vs
Temperature
10mV
5
2mV
5mV
0
0.5mV
1mV
5mV
–5
10mV
13
VS = ±15V
TA = 25°C
1
0
2
–15
3
VS = ±15V
50
0
TEMPERATURE (°C)
–50
120
VS = ±15V
TA = 25°C
100
CMRR (dB)
PSRR
CMRR
60
40
20
125
LT1055/56 G22
0
10
100
1k
10k 100k
FREQUENCY (Hz)
1M
10M
LT1055/56 G23
100
LT1055/56 G21
Common Mode Rejection Ratio vs
Frequency
80
25
75
TEMPERATURE (°C)
–12
LT1055/56 G20
VS = ±10V TO ±17V FOR PSRR
VS = ±15V, VCM = ±10.5V FOR CMRR
–25
–11
SETTLING TIME (µS)
110
90
11
±10
–14
Common Mode and Power Supply
Rejections vs Temperature
100
12
–13
0.5mV
2mV 1mV
LT1055/56 G19
CMRR, PSRR (dB)
LT1055/56 G18
14
–10
3
125
–25
25
75
TEMPERATURE (°C)
15
SETTLING TIME (µS)
120
30
10
–75
8 10
10
OUTPUT VOLTAGE SWING FROM 0V (V)
OUTPUT VOLTAGE SWING FROM 0V (V)
5
100
LT1056 Settling Time
2mV
10mV
RL = 1k
LT1055/56 G17
LT1055 Settling Time
10
300
160
VS = ±15V
TA = 25°C
0
–20
140
BATTERY VOLTAGE (V)
GAIN (dB)
LT1056
LT1055
10
PHASE SHIFT (DEGREES)
60
120
LT1056
LT1055
VS = ±15V
VO = ±10V
RL = 2k
PHASE
100
80
1000
Power Supply Rejection Ratio vs
Frequency
140
POWER SUPPLY REJECTION RATIO (dB)
120
Voltage Gain vs Temperature
100
VOLTAGE GAIN (V/mV)
Gain vs Frequency
140
TA = 25°C
120
100
POSITIVE
SUPPLY
80
NEGATIVE
SUPPLY
60
40
20
0
10
100
100k
10k
1k
FREQUENCY (Hz)
1M
10M
LT1055/56 G24
10556fd
8
For more information www.linear.com/LT1055
LT1055/LT1056
TYPICAL PERFORMANCE CHARACTERISTICS
Supply Current vs Supply Voltage
Output Swing vs Load Resistance
8
TA = –55°C
LT1056
25°C
4
TA = 125°C
TA = –55°C
LT1055
25°C
2
TA = 125°C
9
3
5
10
15
SUPPLY VOLTAGE (V)
20
TA = –125°C
VS = ±15V
0
–3
TA = –25°C
–6
–9
TA = –55°C
–15
0.1
TA = –55°C
40
TA = –25°C
6
–12
0
TA = –55°C
SHORT-CIRCUIT CURRENT (mA)
6
OUTPUT VOLTAGE SWING (V)
SUPPLY CURRENT (mA)
12
0
Short-Circuit Current vs Time
50
15
TA = –125°C
TA = 125°C
20
10
0
VS = ±15V
–10
SINKING
–20
TA = 125°C
–30
TA = 25°C
–40
0.3
1
3
LOAD RESISTANCE (kΩ)
–50
10
LT1055/56 G26
LT1055/56 G25
TA = 25°C
30
TA = –55°C
0
2
1
3
TIME FROM OUTPUT SHORT TO GROUND
(MINUTES)
LT1055/56 G27
APPLICATIONS INFORMATION
The LT1055/LT1056 may be inserted directly into LF155A/
LT355A, LF156A/LT356A, OP-15 and OP-16 sockets.
Offset nulling will be compatible with these devices with
the wiper of the potentiometer tied to the positive supply.
Offset Nulling
V+
Board leakage can be minimized by encircling the input
circuitry with a guard ring operated at a potential close to
that of the inputs: in inverting configurations the guard ring
should be tied to ground, in noninverting connnections
to the inverting input at pin 2. Guarding both sides of the
+
6
OUT
4
V–
LT1055/56 AI1
No appreciable change in offset voltage drift with temperature will occur when the device is nulled with a
potentiometer, RP, ranging from 10k to 200k.
The LT1055/LT1056 can also be used in LF351, LF411,
AD547, AD611, OPA-111, and TL081 sockets, provided
that the nulling cicuitry is removed. Because of the LT1055/
LT1056’s low offset voltage, nulling will not be necessary
in most applications.
N/C
OFFSET
TRIM
V+
7
OUTPUT
8
1
6
Achieving Picoampere/Microvolt Performance
In order to realize the picoampere-microvolt level accuracy
of the LT1055/LT1056 proper care must be exercised. For
2
5
OFFSET
TRIM
4
3
TS
LT1055
LT1056
7
PU
3
5
–
V–
IN
1 RP
2
example, leakage currents in circuitry external to the op
amp can significantly degrade performance. High quality
insulation should be used (e.g. Teflon, Kel-F); cleaning of
all insulating surfaces to remove fluxes and other residues will probably be required. Surface coating may be
necessary to provide a moisture barrier in high humidity
environments.
GUARD
LT1055/56 AI2
10556fd
For more information www.linear.com/LT1055
9
LT1055/LT1056
APPLICATIONS INFORMATION
printed circuit board is required. Bulk leakage reduction
depends on the guard ring width.
The LT1055/LT1056 has the lowest offset voltage of any
JFET input op amp available today. However, the offset
voltage and its drift with time and temperature are still
not as good as on the best bipolar amplifiers because the
transconductance of FETs is considerably lower than that
of bipolar transistors. Conversely, this lower transconductance is the main cause of the significantly faster speed
performance of FET input op amps.
Offset voltage also changes somewhat with temperature
cycling. The AM grades show a typical 20µV hysteresis
(30µV on the M grades) when cycled over the –55°C to
125°C temperature range. Temperature cycling from 0°C
to 70°C has a negligible (less than 10µV) hysteresis effect.
The offset voltage and drift performance are also affected
by packaging. In the plastic N8 package the molding compound is in direct contact with the chip, exerting pressure
on the surface. While NPN input transistors are largely
unaffected by this pressure, JFET device matching and drift
are degraded. Consequently, for best DC performance, as
shown in the typical performance distribution plots, the
TO-5 H package is recommended.
Noise Performance
ing an LT1056 at ±5V supplies or with a 20°C/W caseto-ambient heat sink reduces 0.1Hz to 10Hz noise from
typically 2.5µVP-P (±15V, free-air) to 1.5µVP-P. Similiarly,
the noise of an LT1055 will be 1.8µVP-P typically because
of its lower power dissipation and chip temperature.
High Speed Operation
Settling time is measured in the test circuit shown. This test
configuration has two features which eliminate problems
common to settling time measurments: (1) probe capacitance is isolated from the “false summing” node, and (2)
it does not require a “flat top” input pulse since the input
pulse is merely used to steer current through the diode
bridges. For more details, please see Application Note 10.
As with most high speed amplifiers, care should be taken with
supply decoupling, lead dress and component placement.
When the feedback around the op amp is resistive (RF),
a pole will be created with RF, the source resistance and
capacitance (RS, CS), and the amplifier input capacitance
(CIN ≈ 4pF). In low closed-loop gain configurations and
with RS and RF in the kilohm range, this pole can create
excess phase shift and even oscillation. A small capacitor (CF) in parallel with RF eliminates this problem. With
RS (CS + CIN) = RFCF, the effect of the feedback pole is
completely removed.
The current noise of the LT1055/LT1056 is practically
immeasurable at 1.8fA/√Hz. At 25°C it is negligible up to
1G of source resistance, RS (compound to the noise of
RS). Even at 125°C it is negligible to 100M of RS.
The voltage noise spectrum is characterized by a low 1/f
corner in the 20Hz to 30Hz range, significantly lower than
on other competitive JFET input op amps. Of particular
interest is the fact that with any JFET IC amplifier, the
frequency location of the 1/f corner is proportional to
the square root of the internal gate leakage currents and,
therefore, noise doubles every 20°C. Furthermore, as illustrated in the noise versus chip temperature curves, the
0.1Hz to 10Hz peak-to-peak noise is a strong function of
temperature, while wideband noise (fO = 1kHz) is practically unaffected by temperature.
Consequently, for optimum low frequency noise, chip
temperature should be minimized. For example, operat-
CF
RF
–
RS
CS
CIN
OUTPUT
+
LT1055/56 AI03
Phase Reversal Protection
Most industry standard JFET input op amps (e.g., LF155/
LF156, LF351, LF411, OP15/16) exhibit phase reversal at
the output when the negative common mode limit at the
input is exceeded (i.e., from –12V to –15V with ±15V supplies). This can cause lock-up in servo systems. As shown
below, the LT1055/LT1056 does not have this problem
due to unique phase reversal protection circuitry (Q1 on
simplified schematic).
10556fd
10
For more information www.linear.com/LT1055
LT1055/LT1056
APPLICATIONS INFORMATION
Settling Time Test Circuit
15V
+
0.01 DISC
10pF (TYPICAL)
15k
10µF
SOLID
TANTALUM
10k
–
–15V
0.01 DISC
50Ω
2W
15V
+ 10µF
SOLID
TANTALUM
2k
+
PULSE GEN
INPUT
(5V MIN STEP)
+
2k
LT1055
LT1056
15k
+
10µF
SOLID
TANTALUM
AUT OUTPUT
AMPLIFIER
UNDER
TEST
10k
15k
2N3866
15V
2N160
1/2
U440
HP5082-8210
HEWLETT
PACKARD
0.01 DISC
3Ω
–15V
50Ω
3Ω
2N3866
100Ω
DC ZERO
15k
+
0.01 DISC
OUTPUT
TO SCOPE
15V
1/2
U440
–15V
15V
4.7k
10µF
SOLID TANTALUM
= 1N4148
–15V
2N5160
4.7k
–15V
LT1055/56 AI04
Voltage Follower with Input Exceeding the Negative
Common Mode Range
15V
2
INPUT
±15V
SINE WAVE
3
–
7
LT1055/56
+
4
6
OUTPUT
2k
–15V
LT1055/56 AI05
10V/DIV
10V/DIV
0.5ms/DIV
0.5ms/DIV
0.5ms/DIV
LT1055/56 AI06
Output
LT1055/LT1056
10V/DIV
Output
(LF155/LF56, LF441, OP-15/OP-16)
Input
LT1055/56 AI07
LT1055/56 AI08
10556fd
For more information www.linear.com/LT1055
11
LT1055/LT1056
TYPICAL APPLICATIONS †
Exponential Voltage-to-Frequency Converter for Music Synthesizers
INPUT
0V TO 10V
EXPONENT
TRIM
2500Ω*
11.3k*
5
6
3.57k*
ZERO TRIM
500pF
POLYSTYRENE
15V
500k
2N3904
7
–
500Ω*
6
LT1055
3
+
SAWTOOTH
OUTPUT
–15V
1.1k
4.7k
15V
2
4
2N3906
1k*
562Ω*
LM329
4.7k
10k*
10k*
2
1k*
–
2
+
3
SCALE FACTOR
1V IN OCTAVE OUT
*1% METAL FILM RESISTOR
PIN NUMBERED TRANSISTORS = CA3096 ARRAY
15V
3k
6
LM301A
3
1
15V
7
8
13
8
1
4
0.01µF
7
14
1N148
9
33Ω
15 2.2k
–15V
†For
TEMPERATURE CONTROL LOOP
LT1055/56 TA03
ten additional applications utilizing the
LT1055 and LT1056, please see the LTC1043
data sheet and Application Note 3.
12-Bit Charge Balance A/D Converter
74C00
28k
0.003µF
14k
0.01µF
2
3
249k*
CLK OUTPUT (B)
15V
7
–
10k
6
LT1055
+
10k
33k
6
33k
10k
–
+
15V
2
LT1001
4
OUTPUT
(A)
15V
LM329
15V
7
CLK
Q
74C74
Q
P
CL
2N3904
1N4148
COUPLE
THERMALLY
1N4148
D
4
–15V
1N4148
0V TO 10V INPUT
1N4148
3
CIRCUIT OUTPUT
fOUT (A)
RATIO
fCLK (B)
–15V
LT1055/56 TA04
10556fd
12
For more information www.linear.com/LT1055
LT1055/LT1056
TYPICAL APPLICATIONS
Fast “No Trims” 12-Bit Multiplying CMOS DAC Amplifier
Fast, 16-Bit Current Comparator
RFEEDBACK
REFERENCE
IN
* = 1% FILM RESISTOR
15V
–
OUTPUT
LT1055
IOUT2
DELAY = 250ns
HP5082-2810
IOUT1
TYPICAL 12-BIT
CMOS DAC
4.7k
15V
+
50k*
–
100k*
INPUT
7
6
LT1056
3
LT1009
2.5V
LT1055/56 TA05
2
15V
+
4
2
3
–15V
+
3k
8
7
LT1011
–
OUTPUT
1
4
–15V
LT1055/56 TA06
Temperature-to-Frequency Converter
15V
560Ω
1k*
1k*
15V
2N2222
10k
2N2907
6.2k*
LM329
2k
100°C
ADJ
500Ω
0°C ADJ
6.2k*
0.01µF
POLYSTYRENE
510pF
15V
2
3
–
+
820Ω*
2N2222
4.7k
10k
7
LT1055
2.7k
TTL OUTPUT
0kHz TO 1kHz =
0°C TO 100°C
6
4
–15V
LM134
510Ω
2V
137Ω*
*1% FILM RESISTOR
LT1055/56 TA07
10556fd
For more information www.linear.com/LT1055
13
LT1055/LT1056
TYPICAL APPLICATIONS
100kHz Voltage Controlled Oscillator
15V
2
*1% FILM RESISTOR
=1N4148
100kHz
DISTORTION
TRIM
2k
9.09k*
22.1k
10k*
2
–
7
LT1056
3
+
6 2N4391 2N4391 5k*
4
–15V
4
–15V
2.5k*
68k
FINE
DISTORTION
TRIMS
POLYSTYRENE
500pF
22M
15V
0V TO 10V
INPUT
+
4.5k
1k
15V
50k
10Hz
DISTORTION
TRIM
–15V
2
3
2N4391
+
4
–15V
VR
Y1
Y2
GT
UP
–V
–15V
22k
2
HP50822810
3
+
–15
10k
1k
8
1k
7
LT1011
–
+15V
SINE OUT
2VRMS
0kHs TO 100kHs
5k
FREQUENCY
TRIM
68k
15pF
+V
CC
W
Z1
Z2
10k*
6
LT1056
10k
X1
X2
U1
U2 AD639
COM
15V
15V
7
–
6
LT1056
3
FREQUENCY LINEARITY = 0.1%
FREQUENCY STABILITY = 150ppm/°C
SETTLING TIME = 1.7µs
DISTORTION = 0.25% AT 100kHz,
0.07% AT 10zHz
7
–
1
4
20pF
0.01µF
–15V
10k
LM329
4.7k
–15V
4.7k
15V
LT1055/56 TA08
12-Bit Voltage Output D/A Converter
12-BIT CURRENT OUTPUT D/A
CONVERTER (e.g., 6012,565
OR DAC-80)
CF
2
0 TO 2
OR 4mA
CF = 15pF TO 33pF
SETTLING TIME TO 2mV
(0.8 LSB) = 1.5µs TO 2µs
3
–
15V
7
6
LT1056
+
4
OUTPUT
0V TO 10V
–15V
LT1055/56 TA09
10556fd
14
For more information www.linear.com/LT1055
LT1055/LT1056
SIMPLIFIED SCHEMATIC
NULL
5
7 V+
7k
7k
Q8
Q7
NULL 1
J5
J6
–INPUT 2
+INPUT 3
300Ω
J1
7.5pF
J7
Q9
J2
Q15
Q12
20Ω
Q10
Q11
6 OUTPUT
J3
J8
Q1
14k
Q13
Q14
Q5
8k
200Ω
14k
Q2
9pF
Q3
120µA*
(160)
J4
120µA*
(160)
Q4
800µA*
(1000)
400µA*
(1100)
Q16
3k
50Ω
4 V–
*CURRENTS AS SHOWN FOR LT1055. (X) = CURRENTS FOR LT1056.
LT1055/56 SCHM
10556fd
For more information www.linear.com/LT1055
15
LT1055/LT1056
PACKAGE DESCRIPTION
Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.
H Package
8-Lead TO-5 Metal Can (.200 Inch PCD)
(Reference LTC DWG # 05-08-1320)
.040
(1.016)
MAX
.335 – .370
(8.509 – 9.398)
DIA
.305 – .335
(7.747 – 8.509)
.050
(1.270)
MAX
SEATING
PLANE
.165 – .185
(4.191 – 4.699)
GAUGE
PLANE
.010 – .045*
(0.254 – 1.143)
REFERENCE
PLANE
.500 – .750
(12.700 – 19.050)
.016 – .021**
(0.406 – 0.533)
.027 – .045
(0.686 – 1.143)
45°
PIN 1
.028 – .034
(0.711 – 0.864)
.200
(5.080)
TYP
.110 – .160
(2.794 – 4.064)
INSULATING
STANDOFF
*LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE
AND THE SEATING PLANE
.016 – .024
**FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS
(0.406 – 0.610) H8(TO-5) 0.200 PCD 0204
OBSOLETE PACKAGE
10556fd
16
For more information www.linear.com/LT1055
LT1055/LT1056
PACKAGE DESCRIPTION
Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.
N Package
8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510 Rev I)
.400*
(10.160)
MAX
8
7
6
5
1
2
3
4
.255 ±.015*
(6.477 ±0.381)
.300 – .325
(7.620 – 8.255)
.008 – .015
(0.203 – 0.381)
(
+.035
.325 –.015
8.255
+0.889
–0.381
)
.045 – .065
(1.143 – 1.651)
.065
(1.651)
TYP
.100
(2.54)
BSC
.130 ±.005
(3.302 ±0.127)
.120
(3.048) .020
MIN
(0.508)
MIN
.018 ±.003
(0.457 ±0.076)
N8 REV I 0711
NOTE:
1. DIMENSIONS ARE
INCHES
MILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
10556fd
For more information www.linear.com/LT1055
17
LT1055/LT1056
PACKAGE DESCRIPTION
Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610 Rev G)
.189 – .197
(4.801 – 5.004)
NOTE 3
.045 ±.005
.050 BSC
8
.245
MIN
.160 ±.005
.010 – .020
× 45°
(0.254 – 0.508)
NOTE:
1. DIMENSIONS IN
5
.150 – .157
(3.810 – 3.988)
NOTE 3
1
RECOMMENDED SOLDER PAD LAYOUT
.053 – .069
(1.346 – 1.752)
0°– 8° TYP
.016 – .050
(0.406 – 1.270)
6
.228 – .244
(5.791 – 6.197)
.030 ±.005
TYP
.008 – .010
(0.203 – 0.254)
7
.014 – .019
(0.355 – 0.483)
TYP
INCHES
(MILLIMETERS)
2. DRAWING NOT TO SCALE
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
4. PIN 1 CAN BE BEVEL EDGE OR A DIMPLE
2
3
4
.004 – .010
(0.101 – 0.254)
.050
(1.270)
BSC
SO8 REV G 0212
10556fd
18
For more information www.linear.com/LT1055
LT1055/LT1056
REVISION HISTORY
(Revision history begins at Rev D)
REV
DATE
DESCRIPTION
D
08/15
Corrected application circuit.
PAGE NUMBER
20
10556fd
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection
of its circuits
as described
herein will not infringe on existing patent rights.
For more
information
www.linear.com/LT1055
19
LT1055/LT1056
TYPICAL APPLICATION
±120V Output Precision Op Amp
125V
±25mA OUTPUT
HEAT SINK OUTPUT
TRANSISTORS
1µF
10k
330Ω
510Ω
2N5415
1N965
100pF
10k
2N3440
50k
2
INPUT
10k
3
–
+
1M
2N2222
1k
27Ω
1N4148
7
6
LT1055
OUTPUT
4
1N4148
50k
2N2907
1M
1k
27Ω
2N5415
2N3440
1N965
10k
33pF
100k
510Ω
1µF
330Ω
–125V
LT1055/56 TA10
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1122
Fast Settling JFET Op Amp
340ns Settling Time, GBW = 14MHz, SR = 60V/µs
LT1792
Low Noise JFET Op Amp
en = 6nV/√Hz Max at f = 1kHz
10556fd
20 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
For more information www.linear.com/LT1055
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com/LT1055
LT 0815 REV D • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 1994