LT1457
Dual, Precision
JFET Input Op Amp
FEATURES
s
s
s
s
s
s
s
s
DESCRIPTION
The LT1457 is a dual, JFET input op amp optimized for
handling large capacitive loads in combination with preci-
sion performance.
Precision specifications include 220µV offset voltage in
plastic and surface mount packages. At 70°C input bias
current is 50pA, input offset current is 20pA. Channel
separation is 130dB.
Other dual JFET input op amps from Linear Technology
include the LT1057, which is three times faster than the
LT1457 but at the expense of significantly lower capacitive
load handling capability; and the LT1113 with 4.5nV/√Hz
voltage noise.
Handles 10,000pF Capacitive Load
450µV Max Offset Voltage
1200µV Max Offset Voltage in S8 Package
50pA Bias Current at 70°C
13nV/√Hz Voltage Noise
4V/µs Slew Rate
4µV/°C Drift
130dB Channel Separation
APPLICATIONS
s
s
s
s
Sample-and-Hold (Drives Large Hold Capacitors)
A/D and D/A Converters
Photodiode Amplifiers
Voltage-to-Frequency Converters
TYPICAL PERFORMANCE CHARACTERISTICS
Capacitive Load Handling
100
V
S
= ±15V
T
A
= 25°C
A
V
= +1
PERCENT OF UNITS
21
18
15
12
9
6
3
0
0.1
0
–1.0 –0.8 –0.6 –0.4 –0.2 0 0.2 0.4 0.6 0.8 1.0
INPUT OFFSET VOLTAGE (mV)
LT1457 • TA02
Input Offset Voltage Distribution
S8 Package
V
S
=
±15V
T
A
= 25°C
400 DUALS
(800 OP AMPS)
TESTED FROM
3 RUNS
80
OVERSHOOT (%)
60
40
20
1
10
CAPACITIVE LOAD (nF)
100
LT11457• TA01
U
U W
U
1
LT1457
ABSOLUTE
MAXIMUM
RATINGS
Supply Voltage ......................................................
±20V
Differential Input Voltage .......................................
±40V
Input Voltage .......................... Equal to Supply Voltages
Output Short-Circuit Duration .......................... Indefinite
Operating Temperature Range ................ – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
PACKAGE/ORDER INFORMATION
TOP VIEW
OUT A
–IN A
+IN A
V
–
1
2
A
3
4
B
6
5
–IN B
+IN B
8
7
V
+
OUT B
ORDER PART
NUMBER
LT1457ACN8
LT1457CN8
N8 PACKAGE
8-LEAD PLASTIC DIP
T
JMAX
= 115°C,
θ
JA
= 130°C/ W
TOP VIEW
+IN A
V
–
+IN B
–IN B
1
2
3
4
B
S8 PACKAGE
8-LEAD PLASTIC SOIC
NOTE: THIS PIN CONFIGURATION DIFFERS FROM
THE 8-LEAD DIP PIN LOCATIONS. INSTEAD, IT
FOLLOWS THE INDUSTRY STANDARD LT1013DS8
SO PACKAGE CONFIGURATION.
A
8
7
6
5
–IN A
OUT A
V
+
OUT B
LT1457S8
S8 PART MARKING
1457
T
JMAX
= 130°C,
θ
JA
= 190°C/ W
Consult factory for Industrial and Military grade parts.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
V
OS
Input Offset Voltage
I
OS
I
B
Input Offset Current
Input Bias Current
Input Resistance-Differential
-Common-Mode
Input Capacitance
e
n
e
n
i
n
A
VOL
Input Noise Voltage
Input Noise Voltage Density
Input Noise Current Density
Large-Signal Voltage Gain
Input Voltage Range
CMRR
PSRR
V
OUT
SR
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing
Slew Rate
V
CM
=
±10.5V
0.1Hz to 10Hz
CONDITIONS
LT1457AC/C
LT1457S8
V
S
=
±15V,
T
A
= 25°C,V
CM
= 0V unless otherwise noted. (Note 1)
LT1457AC
MIN TYP
MAX
150
450
3
±5
10
12
10
12
10
11
4
2.0
26
13
1.5
150
120
±10.5
86
88
±12
2
350
250
14.3
–11.5
100
103
±13
4
22
4
100
80
±10.5
82
86
±12
2
40
±50
LT1457C/LT1457S8
MIN
TYP
MAX
200
800
220
1200
4
±7
10
12
10
12
10
11
4
2.1
28
14
1.8
300
220
14.3
–11.5
98
102
±13
4
24
6
50
±75
UNITS
µV
µV
pA
pA
Ω
Ω
Ω
pF
µV
P–P
nV/√Hz
nV/√Hz
fA/√Hz
V/mV
V/mV
V
V
dB
dB
V
V/µs
Fully Warmed Up
Fully Warmed Up
V
CM
= –11V to 8V
V
CM
= 8V to 11V
f
O
= 10Hz
f
O
= 1kHz (Note 2)
f
O
= 10Hz, 1kHz (Note 3)
V
O
=
±10V,
R
L
= 2k
V
O
=
±10V,
R
L
= 1k
V
S
=
±4.5V
to
±18V
R
L
= 2k
2
U
W
U
U
W W
W
LT1457
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
GBW
I
S
Gain-Bandwidth Product
Supply Current Per Amplifier
Channel Separation
CONDITIONS
(Note 5)
V
S
=
±15V,
T
A
= 25°C,V
CM
= 0V unless otherwise noted. (Note 1)
LT1457AC
MIN TYP
MAX
1.0
1.7
1.8
3.0
132
LT1457C/LT1457S8
MIN
TYP
MAX
1.0
1.7
1.8
130
3.0
UNITS
MHz
mA
dB
DC to 5kHz, V
IN
=
±10V
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
Input Offset Voltage
V
OS
Average Temperature Coefficient of
Input Offset Voltage (Note 4)
Input Offset Current
Input Bias Current
Large-Signal Voltage Gain
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing
Supply Current Per Amplifier
CONDITIONS
LT1457AC/C
LT1457S8
V
S
=
±15V,
V
CM
= 0V, 0°C
≤
T
A
≤
70°C, unless otherwise noted.
MIN
q
q
q
LT1457AC
TYP
MAX
250
900
3
18
±50
220
98
102
±12.8
1.7
10
150
±250
LT1457C/LT1457S8
MIN
TYP
MAX
330
1500
400
1900
4
16
20
±60
200
96
100
±12.8
1.7
250
±350
UNITS
µV
µV
µV/°C
pA
pA
V/mV
dB
dB
V
mA
mA
I
OS
I
B
A
VOL
CMRR
PSRR
V
OUT
I
S
Warmed Up, T
A
= 70°C
Warmed Up, T
A
= 70°C
V
O
=
±10V,
R
L
= 2k
V
CM
=
±10.4V
V
S
=
±4.5V
to
±18V
R
L
= 2k
T
A
= 70°C
q
q
q
q
q
70
85
87
±12
50
80
84
±12
3.2
3.2
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
Input Offset Voltage
V
OS
Average Temperature Coefficient of
Input Offset Voltage
Input Offset Current
Input Bias Current
Large-Signal Voltage Gain
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing
Supply Current Per Amplifier
CONDITIONS
LT1457AC/C
LT1457S8
V
S
=
±15V,
V
CM
= 0V, –40°C
≤
T
A
≤
85°C, unless otherwise noted. (Note 6)
LT1457AC
MIN TYP
MAX
350
1100
3
0.1
±
0.2
120
97
100
±12.7
1.7
10
0.5
±
0.7
30
80
83
±12
3.8
1.7
LT1457C/LT1457S8
MIN
TYP
MAX
400
1800
500
2300
4
16
0.1
±0.2
110
95
98
±12.6
0.6
±0.9
UNITS
µV
µV
µV/°C
nA
nA
V/mV
dB
dB
V
mA
mA
q
q
q
I
OS
I
B
A
VOL
CMRR
PSRR
V
OUT
I
S
Warmed Up, T
A
= 85°C
Warmed Up, T
A
= 85°C
V
O
=
±10V,
R
L
= 2k
V
CM
=
±10.4V
V
S
=
±5V
to
±17V
R
L
= 2k
T
A
= – 40°C
T
A
= 85°C
q
q
q
q
40
84
86
±12
3.8
The
q
denotes the specifications which apply over the full operating
temperature range.
Note 1:
Typical parameters are defined as the 60% yield of distributions of
individual amplifiers; i.e., out of 100 LT1457s (200 op amps) typically 120
will be better than the indicated specification.
Note 2:
This parameter is tested on a sample basis only.
Note 3:
Current noise is calculated from the formula: i
n
= (2qI
b
)
1/2
, where
q = 1.6 x 10
–19
coulomb. The noise of source resistors up to 1GΩ
swamps the contribution of current noise.
Note 4:
This parameter is not 100% tested.
Note 5:
Gain-Bandwidth product is not tested. It is guaranteed by design
and by inference from the slew rate measurement.
Note 6:
The LT1457 is not tested and not quality-assurance-sampled at
– 40°C and at 85°C. These specifications are guaranteed by design,
correlation, and/or inference from 0°C, 25°C, and 70°C tests.
3
LT1457
TYPICAL PERFORMANCE CHARACTERISTICS
Input Bias and Offset Current vs
Temperature
1000
160
INPUT BIAS AND OFFSET CURRENT (pA)
INPUT BIAS CURRENT (pA)
300
CHANGE IN OFFSET VOLTAGE (µV)
V
S
= ±15V
V
CM
= 0V
WARMED UP
100
BIAS CURRENT
30
10
OFFSET CURRENT
3
0
25
50
75
AMBIENT TEMPERATURE (°C)
100
Input Offset Voltage Distribution
N8 Package
24
21
V
S
=
±15V
T
A
= 25°C
1000
OFFSET VOLTAGE CHANGE (µV)
VOLTAGE GAIN (V/mV)
PERCENT OF UNITS
18
15
12
9
6
3
900 DUALS
(1800 OP AMPS)
TESTED FROM 3
RUNS
0
0.2 0.4 0.6 0.8
–0.8 –0.6 –0.4 –0.2 0
INPUT OFFSET VOLTAGE (mV)
LT1457 • TPC04
Voltage Noise vs Frequency
100
RMS VOLTAGE NOISE DENSITY (nV/√Hz)
70
50
V
S
= ±15V
T
A
= 25°C
CHANNEL SEPARATION (dB)
NOISE VOLTAGE (1µV/DIV)
30
20
1/f CORNER = 28Hz
10
3
10
30
100 300 1k
FREQUENCY (Hz)
3k
10k
0
2
4
6
TIME (SECONDS)
8
10
4
U W
LT1457 • TPC01
LT1457 • TPC07
Input Bias Current Over
the Common-Mode Range
150
V
S
= ±15V
120
140
120
100
80
60
40
20
0
–20
–15
T
A
= 25°C
0
–10
–5
0
5
10
COMMON-MODE INPUT VOLTAGE (V)
15
T
A
= 70°C
Warm-Up Drift
V
S
= ±15V
T
A
= 25°C
90
S8 PACKAGE
60
N8 PACKAGE
30
0
1
2
3
4
TIME AFTER POWER ON (MINUTES)
5
LT1457 • TPC02
LT1457 • TPC03
Voltage Gain vs Temperature
50
R
L
= 2k
300
R
L
= 1k
100
V
S
= ±15V
V
O
= ±10V
40
30
20
10
0
–10
–20
–30
–40
10
–50
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
Long Term Drift of
Representative Units
V
S
= ±15V
T
A
= 25°C
30
0
1
2
3
TIME (MONTHS)
4
5
LT1457 • TPC05
LT1457 • TPC06
0.1Hz to 10Hz Noise
160
V
S
= ±15V
T
A
= 25°C
Channel Separation vs Frequency
140
LIMITED BY
THERMAL
INTERACTION AT
DC = 132dB
LIMITED BY PIN TO
PIN CAPACITANCE
V
S
= ±15V
T
A
= 25°C
V
IN
= 20V
P-P
TO 5kHz
R
L
= 2k
1
10
R
S
= 10Ω
120
100
80
R
S
= 1k
100k
1M
60
100
1k
10k
FREQUENCY (Hz)
LT1457 • TPC08
LT1457 • TPC09
LT1457
TYPICAL PERFORMANCE CHARACTERISTICS
Common-Mode Rejection Ratio
vs Frequency
120
100
80
V
S
= ±15V
T
A
= 25°C
COMMON -MODE RANGE (V)
15
14
13
CMRR, PSRR (dB)
12
11
±10
–11
–12
–13
–14
0
10
100
1k
10k 100k
FREQUENCY (Hz)
1M
10M
–15
–50
V
S
= ±15V
– 25
0
25
50
TEMPERATURE (°C)
75
100
90
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
110
PSRR
CMRR (dB)
60
40
20
Slew Rate, Gain-Bandwidth
Product vs Temperature
10
V
S
= ±15V
8
SUPPLY CURRENT PER AMPLIFIER (mA)
2.5
3
SHORT-CIRCUIT CURRENT (mA)
SLEW RATE (V/µs)
SLEW FALL
6
GBW
4
SLEW RISE
2
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
1.0
Gain, Phase vs Frequency
25
20
15
PEAK TO PEAK OUTPUT SWING (V)
PHASE MARGIN = 80°, C
L
= 10pF
PHASE MARGIN = 51°, C
L
= 1000pF
C
L
= 10pF
PHASE
C
L
= 1000pF
GAIN
VOLTAGE GAIN (dB)
PSRR (dB)
10
5
0
–5
–10
–15
0.1
V
S
= ±15V
T
A
= 25°C
C
L
= 1000pF
C
L
= 10pF
10
LT1457 • TPC16
1.0
FREQUENCY (MHz)
U W
LT1457• TPC10
LT1457 • TPC18
Common-Mode Range vs
Temperature
120
Common-Mode and Power Supply
Rejections vs Temperature
V
S
= ±5V TO ±17V FOR PSRR
V
S
= ±15V, V
CM
= ±10.5V FOR CMRR
CMRR
100
LT1457 • TPC11
LT1457 • TPC12
Supply Current vs Temperature
50
40
30
20
10
0
–10
–20
–30
– 40
0
–50
– 50
–25
0
25
50
TEMPERATURE (°C)
75
100
Short-Circuit Current vs Time
(One Output Shorted to Ground)
T
A
= – 40°C
2.0
2
V
S
= ±15V
V
S
= ±5V
GBW (MHz)
PHASE MARGIN (DEG)
T
A
= 25°C
T
A
= 25°C
T
A
= 85°C
T
A
= 85°C
1.5
1
T
A
= – 40°C
V
S
= ±15V
0
1
2
3
TIME FROM OUTPUT SHORT TO GROUND (MINUTES)
LT1457 • TPC15
LT1457 • TPC14
Undistorted Output Swing vs
Frequency
30
100
80
60
40
20
0
–20
V
S
= ±15V
T
A
= 25°C
24
100
18
80
60
40
6
20
0
10k
0
100k
1M
FREQUENCY (Hz)
10M
LT11457• TPC17
Power Supply Rejection Ratio
vs Frequency
140
T
A
= 25°C
120
POSITIVE
SUPPLY
NEGATIVE
SUPPLY
12
10
100
1k
10k 100k
FREQUENCY (Hz)
1M
10M
LT1457• TPC13
5
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