LT1789-1 [Linear]
Micropower, Single Supply Rail-to-Rail Output Instrumentation Amplifiers; 微功耗，单电源轨至轨输出仪表放大器
| 型号： | LT1789-1 |
| 厂家： | 
Linear |
| 描述： | Micropower, Single Supply Rail-to-Rail Output Instrumentation Amplifiers |
| 文件： | 总24页 (文件大小：510K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LT1789-1/LT1789-10
Micropower,
Single Supply Rail-to-Rail
Output Instrumentation Amplifiers
U
FEATURES
DESCRIPTIO
The LT®1789-1/LT1789-10 are micropower, precision in-
strumentation amplifiers that are optimized for single supply
operation from 2.2V to 36V. The quiescent current is 95µA
max, the inputs common mode to ground and the output
swings within 110mV of ground. The gain is set with a single
external resistor for a gain range of 1 to 1000 for the LT1789-
1 and 10 to 1000 for the LT1789-10.
■
Micropower: 95µA Supply Current Max
■
Low Input Offset Voltage: 100µV Max
■
Low Input Offset Voltage Drift: 0.5µV/°C Max
Single Gain Set Resistor:
■
G = 1 to 1000 (LT1789-1)
G = 10 to 1000 (LT1789-10)
Inputs Common Mode to V–
Wide Supply Range: 2.2V to 36V Total Supply
CMRR at G = 10: 96dB Min
■
■
■
■
■
■
■
■
■
The high accuracy of the LT1789-1 (40ppm maximum
nonlinearity and 0.25% max gain error) is unmatched by
othermicropowerinstrumentationamplifiers.TheLT1789-10
maximizesboththeinputcommonmoderangeanddynamic
output range when an amplification of 10 or greater is
required, allowing precise signal processing where other
instrumentation amplifiers fail to operate. The LT1789-1/
LT1789-10 are laser trimmed for very low input offset
voltage, low input offset voltage drift, high CMRR and high
PSRR. The output can handle capacitive loads up to 400pF
(LT1789-1), 1000pF (LT1789-10) in any gain configuration
whiletheinputsareESDprotectedupto10kV(humanbody).
Gain Error: G = 10, 0.25% Max
Gain Nonlinearity: G = 10, 40ppm Max
Input Bias Current: 40nA Max
PSRR at G = 10: 100dB Min
1kHz Voltage Noise: 48nV/√Hz
0.1Hz to 10Hz Noise: 1.5µVP-P
U
APPLICATIO S
■
Portable Instrumentation
■
Bridge Amplifiers
■
Strain Gauge Amplifiers
The LT1789-1/LT1789-10 are offered in the 8-pin SO pack-
age, requiring significantly less PC board area than discrete
multi op amp and resistor designs.
■
Thermocouple Amplifiers
■
Differential to Single-Ended Converters
■
Medical Instrumentation
, LTC and LT are registered trademarks of Linear Technology Corporation.
U
TYPICAL APPLICATIO
0.5A to 4A Voltage Controlled Current Source
C1
4700pF
V
S
C3
V
S
120Ω
R1
8k
0.1µF
90.9k
–
+
7
2
3
R3
100Ω
TIP127*
V
IN
6
R2
10k
LT1636
*ENSURE ADEQUATE POWER
DISSIPATION CAPABILITY AT
HIGHER VOLTAGES,
V
S
5
4
7
3
8
+
–
3
4
CURRENTS AND DUTY CYCLES
R4
10k
1
2
6
R
*
I
LT1789-1
4
SENSE
0.1Ω
REF
5
LOAD
C2
3300pF
1
2
V
S
= 3.3V TO 32V
V
IN
I
=
LOAD
R
• 10
SENSE
= 1A PER VOLT AS SHOWN
R
LOAD
*
RISE TIME ≈ 250µs, 10% TO 90%,
1A TO 2A OUTPUT STEP INTO 0.25Ω LOAD
1789 TA01
1789f
1
LT1789-1/LT1789-10
W W
U W
U W
U
ABSOLUTE AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
(Note 1)
Supply Voltage (V+ to V–) ........................................ 36V
Input Differential Voltage ......................................... 36V
Input Current (Note 3) ........................................ ±20mA
Output Short-Circuit Duration.......................... Indefinite
Operating Temperature Range ................ –40°C to 85°C
Specified Temperature Range (Note 4)
LT1789C-1, LT1789C-10 .................... –40°C to 85°C
LT1789I-1, LT1789I-10 ...................... –40°C to 85°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
TOP VIEW
LT1789CS8-1
LT1789IS8-1
LT1789CS8-10
LT1789IS8-10
R
1
2
3
4
8
7
6
5
R
G
G
–IN
+IN
+V
S
OUT
REF
–V
S
S8 PART MARKING
S8 PACKAGE
8-LEAD PLASTIC SO
17891
1789I1
178910
789I10
TJMAX = 150°C, θJA = 190°C/ W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
3V and 5V ELECTRICAL CHARACTERISTICS
VS = 3V, 0V; VS = 5V, 0V; RL = 20k, VCM = VREF = half supply, TA = 25°C, unless otherwise noted.
LT1789-1
LT1789-10
TYP
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX
MIN
MAX
UNITS
G
Gain Range
LT1789-1, G = 1 + (200k/R )
1
1000
G
LT1789-10, G = 10 • [1+ (200k/R )]
10
1000
G
Gain Error (Note 6)
G = 1, V = 0.1V to (+V ) – 1V
0.02
0.20
%
O
S
LT1789-1, V = 0.1V to (+V ) – 0.3V
O
S
LT1789-10, V = 0.2V to (+V ) – 0.3V
O
S
G = 10, (Note 2)
0.06
0.06
0.13
0.25
0.27
0.01
0.09
0.16
0.25
0.30
%
%
%
G = 100, (Note 2)
G = 1000, (Note 2)
Gain Nonlinearity (Note 6)
G = 1, V = 0.1V to (+V ) – 1V
35
100
ppm
O
S
LT1789-1, V = 0.1V to (+V ) – 0.3V
O
S
LT1789-10, V = 0.2V to 4.7V, V = 5V
O
S
(Note 8)
G = 10
12
18
90
40
75
15
20
100
100
100
ppm
ppm
ppm
G = 100
G = 1000
V
V
V
Total Input Referred Offset Voltage
Input Offset Voltage
V
= V + V /G
OST
OST OSI OSO
G = 1000
15
150
0.2
19
100
750
4
20
650
0.2
19
160
3000
4
µV
µV
nA
nA
OSI
Output Offset Voltage
Input Offset Current
G = 1 (LT1789-1), G =10 (LT1789-10)
OSO
I
I
(Note 6)
(Note 6)
OS
Input Bias Current
40
40
B
e
n
Input Noise Voltage,
RTI (Referred to Input)
G = 1, f = 0.1Hz to 10Hz
5.0
1.5
1.0
µV
P-P
µV
P-P
µV
P-P
O
G = 10
4.6
1.1
G = 100, 1000
1789f
2
LT1789-1/LT1789-10
3V and 5V ELECTRICAL CHARACTERISTICS
VS = 3V, 0V; VS = 5V, 0V; RL = 20k, VCM = VREF = half supply, TA = 25°C, unless otherwise noted.
LT1789-1
TYP
LT1789-10
SYMBOL PARAMETER
CONDITIONS
MIN
MAX
MIN
TYP
MAX
UNITS
2
2
Total RTI Noise = √e + (e /G)
ni
no
e
Input Noise Voltage Density,
RTI
f = 1kHz (Note 7)
48
85
52
90
nV/√Hz
nV/√Hz
ni
O
e
Output Noise Voltage Density, f = 1kHz (Note 3)
RTI
330
270
no
O
i
Input Noise Current
Input Noise Current Density
Input Resistance
f = 0.1Hz to 10Hz
16
62
16
62
pA
P-P
n
O
f = 1kHz
O
fA/√Hz
GΩ
R
V
= 0V to (+V ) – 1V (Note 6)
0.75
0
1.6
0.75
0
1.6
IN
IN
S
C
Input Capacitance
Differential
Common Mode
1.6
1.6
1.6
1.6
pF
pF
IN
V
Input Voltage Range
+V – 1
S
+V – 1.2
S
V
CM
CMRR
Common Mode Rejection Ratio 1k Source Imbalance, (Note 6)
LT1789-1,V = 0V to (+V )–1V
CM
S
LT1789-10, V = 0V to (+V )–1.2V
CM
S
G = 1
79
96
100
100
88
dB
dB
dB
dB
G = 10
G = 100
G = 1000
106
114
114
88
98
98
105
113
113
PSRR
Power Supply Rejection Ratio V = 2.5V to 12.5V, V = V = 1V
S
CM
REF
G = 1
G = 10
G = 100
G = 1000
90
100
113
116
116
dB
dB
dB
dB
100
102
102
94
102
102
109
120
120
Minimum Supply Voltage
Supply Current
2.2
67
54
2.5
95
2.2
67
62
2.5
95
V
µA
mV
V
I
(Note 7)
S
V
V
Output Voltage Swing LOW
Output Voltage Swing HIGH
Short-Circuit Current
(Note 7)
100
110
OL
OH
(Note 7)
+V – 0.3 +V – 0.19
+V – 0.3 +V – 0.19
S S
S
S
I
Short to GND
Short to +V
2.2
8.5
2.2
8.5
mA
mA
SC
S
BW
SR
Bandwidth
G = 1
60
30
3
kHz
kHz
kHz
kHz
G = 10
G = 100
G = 1000
25
12
1.5
0.2
Slew Rate
G = 10, V
4V Step
= 0.5V to 4.5V
0.023
240
0.062
190
V/µs
µs
OUT
Settling Time to 0.01%
Reference Input Resistance
Reference Input Current
Reference Gain to Output
R
REFIN
220
220
kΩ
µA
I
V
= 0V
2.7
2.7
REFIN
REF
AV
REF
1 ±0.0001
1 ±0.0001
1789f
3
LT1789-1/LT1789-10
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of
0°C ≤ TA ≤ 70°C. VS = 3V, 0V; VS = 5V, 0V; RL = 20k, VREF = half supply, unless otherwise noted. (Note 4)
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
Gain Error (Note 6)
CONDITIONS
G = 1, V = 0.3V to (+V ) – 1V
MIN
MAX
MIN
MAX
UNITS
●
0.25
%
O
S
V = 0.3V to (+V ) – 0.5V
O
S
G = 10 (Note 2)
●
●
0.53
0.55
0.30
0.53
%
%
G = 100 (Note 2)
Gain Nonlinearity (Note 6)
G = 1, V = 0.3V to (+V ) – 1V
●
185
ppm
O
S
LT1789-1, V = 0.3V to (+V ) – 0.5V
O
S
LT1789-10, V = 0.3V to 4.7V, V = 5V
O
S
(Note 8)
G = 10
G = 100
●
●
90
120
130
130
ppm
ppm
G/T
Gain vs Temperature
G < 1000 (Notes 2, 3)
Total Input Referred Offset Voltage V = V + V /G
OST
●
5
3
50
5
3
50
ppm/°C
V
V
V
V
V
V
V
OST
OSI
OSO
Input Offset Voltage
G = 1000
●
●
●
●
●
●
●
●
●
●
●
150
10
190
10
µV
µV
OSI
Input Offset Voltage Hysteresis
Output Offset Voltage
(Notes 3, 5)
OSIH
OSO
OSOH
G = 1 (LT1789-1), G = 10 (LT1789-10)
950
100
0.5
4
3700
900
0.7
µV
Output Offset Voltage Hysteresis (Notes 3, 5)
50
0.2
1.5
300
0.3
7
µV
/T
Input Offset Voltage Drift (RTI)
Output Offset Voltage Drift
Input Offset Current
(Note 3)
(Note 3)
(Note 6)
µV/°C
µV/°C
nA
OSI
/T
20
OSO
I
I
I
4.5
4.5
OS
/T
Input Offset Current Drift
Input Bias Current
3
3
pA/°C
nA
OS
B
(Note 6)
45
45
I /T
B
Input Bias Current Drift
Input Voltage Range
50
50
pA/°C
V
V
0.2
(+V ) – 1
0.2
(+V ) – 1.5
CM
S
S
CMRR
Common Mode Rejection Ratio
1k Source Imbalance, (Note 6)
LT1789-1, V = 0.2V to (+V ) – 1V
CM
S
LT1789-10, V = 0.2V to (+V ) – 1.5V
CM
S
G = 1
●
●
●
77
94
98
dB
dB
dB
G = 10
85
96
G = 100, 1000
PSRR
Power Supply Rejection Ratio
V = 2.5V to 12.5V, V = V = 1V
S
CM
REF
G = 1
●
●
●
88
98
100
dB
dB
dB
G = 10
G = 100, 1000
92
100
Minimum Supply Voltage
Supply Current
●
●
●
●
2.5
115
110
2.5
115
120
V
µA
mV
V
I
(Note 7)
(Note 7)
(Note 7)
S
V
V
Output Voltage Swing LOW
Output Voltage Swing HIGH
OL
OH
+V – 0.38
S
+V – 0.38
S
1789f
4
LT1789-1/LT1789-10
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range
of –40°C ≤ TA ≤ 85°C. VS = 3V, 0V; VS = 5V, 0V; RL = 20k, VREF = half supply, unless otherwise noted. (Note 4)
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
Gain Error (Note 6)
CONDITIONS
G = 1, V = + 0.3V to (+V ) – 1V
MIN
MAX
MIN
MAX
UNITS
●
0.30
%
O
S
V = 0.3V to (+V ) – 0.5V
O
S
G = 10 (Note 2)
●
●
0.57
0.59
0.35
0.62
%
%
G = 100 (Note 2)
Gain Nonlinearity (Note 6)
G = 1, V = 0.3V to (+V ) – 1V
●
250
ppm
O
S
LT1789-1, V = 0.3V to (+V ) – 0.5V
O
S
LT1789-10, V = 0.3V to 4.7V, V = 5V
O
S
(Note 8)
G = 10
G = 100
●
●
105
160
150
170
ppm
ppm
G/T
Gain vs Temperature
G < 1000 (Notes 2, 3)
Total Input Referred Offset Voltage V = V + V /G
OST
●
5
3
50
5
3
50
ppm/°C
V
V
V
V
V
V
V
OST
OSI
OSO
Input Offset Voltage
G = 1000
●
●
●
●
●
●
●
●
●
●
●
175
10
205
10
µV
µV
OSI
Input Offset Voltage Hysteresis
Output Offset Voltage
(Notes 3, 5)
OSIH
OSO
OSOH
G = 1 (LT1789-1), G = 10 (LT1789-10)
1050
100
0.5
4
4000
900
0.7
20
µV
Output Offset Voltage Hysteresis (Notes 3, 5)
50
0.2
1.5
300
0.3
7
µV
/T
Input Offset Voltage Drift (RTI)
Output Offset Voltage Drift
Input Offset Current
(Note 3)
(Note 3)
(Note 6)
µV/°C
µV/°C
nA
OSI
/T
OSO
I
I
I
5
5
OS
/T
Input Offset Current Drift
Input Bias Current
3
3
pA/°C
nA
OS
B
(Note 6)
50
50
I /T
B
Input Bias Current Drift
Input Voltage Range
50
50
pA/°C
V
V
0.2
+V – 1 0.2
S
+V – 1.5
CM
S
CMRR
Common Mode Rejection Ratio
1k Source Imbalance, (Note 6)
LT1789-1 V = 0.2V to (+V ) – 1V
CM
S
LT1789-10 V = 0.2V to (+V ) – 1.5V
CM
S
G = 1
●
●
●
75
92
96
dB
dB
dB
G = 10
84
94
G = 100, 1000
PSRR
Power Supply Rejection Ratio
V = 2.5V to 12.5V, V = V = 1V
S
CM
REF
G = 1
●
●
●
86
96
98
dB
dB
dB
G = 10
G = 100, 1000
90
98
Minimum Supply Voltage
Supply Current
●
●
●
●
2.5
125
120
2.5
125
130
V
µA
mV
V
I
(Note 7)
(Note 7)
(Note 7)
S
V
V
Output Voltage Swing LOW
Output Voltage Swing HIGH
OL
OH
+V – 0.40
S
+V – 0.40
S
1789f
5
LT1789-1/LT1789-10
ELECTRICAL CHARACTERISTICS
VS = ±15V, RL = 20k, VCM = VOUT = 0V, TA = 25°C, unless otherwise noted.
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
CONDITIONS
LT1789-1, G = 1 + (200k/R )
MIN
MAX
MIN
MAX
UNITS
G
Gain Range
1
1000
G
LT1789-10, G = 10 • [1 + (200k/R )]
10
1000
G
Gain Error
V = ±10V
G = 1
G = 10 (Note 2)
G = 100 (Note 2)
G = 1000 (Note 2)
O
0.01
0.04
0.04
0.07
0.10
0.15
0.15
0.20
%
%
%
%
0.01
0.03
0.03
0.15
0.20
0.25
Gain Nonlinearity
V = ±10V
G = 1
G = 10
G = 100
G = 1000
O
8
1
6
20
10
20
ppm
ppm
ppm
ppm
5
5
25
40
40
160
20
100
V
V
V
Total Input Referred Offset Voltage V
= V + V /G
OST
OST OSI OSO
Input Offset Voltage
Output Offset Voltage
Input Offset Current
Input Bias Current
G = 1000
G = 1 (LT1789-1), G = 10 (LT1789-10)
30
200
0.2
17
235
1
30
0.6
0.2
17
295
3.3
4
µV
mV
nA
OSI
OSO
I
I
4
OS
40
40
nA
B
e
n
Input Noise Voltage, RTI
f = 0.1Hz to 10Hz
G = 1
G = 10
G = 100, 1000
O
5.0
1.5
1.0
µV
µV
µV
P-P
P-P
P-P
4.6
1.1
2
2
Total RTI Noise = √e + (e /G)
ni
no
e
e
Input Noise Voltage Density, RTI f = 1kHz
49
330
19
90
14
53
270
19
95
14
nV/√Hz
nV/√Hz
ni
O
Output Noise Voltage Density, RTI f = 1kHz
no
O
i
Input Noise Current
Input Noise Current Density
Input Resistance
f = 0.1Hz to 10Hz
pA
P-P
n
O
f = 1kHz
O
100
4.7
62
pA/√Hz
GΩ
R
2
2
4.7
IN
C
Input Capacitance
Differential
Common Mode
20
17
20
17
pF
pF
IN
V
Input Voltage Range
–15
–15
V
CM
CMRR
Common Mode Rejection Ratio
1k Source Imbalance, V = –15V to 14V
G = 1
G = 10
G = 100, 1000
CM
80
98
102
89
108
117
dB
dB
dB
93
102
108
123
PSRR
Power Supply Rejection Ratio
LT1789-1, V = ±1.25V to ±16V
S
LT1789-10, V = ±1.50V to ±16V
S
G = 1
G = 10
G = 100, 1000
94
104
106
107
118
121
dB
dB
dB
100
106
115
129
Minimum Supply Voltage
Supply Current
±1.25
±1.50
V
µA
V
I
85
130
85
130
S
V
Output Voltage Swing
Short-Circuit Current
±14.5 ±14.7
±14.5 ±14.7
O
I
Short to –V
Short to +V
2.2
8.5
2.2
8.5
mA
mA
SC
S
S
1789f
6
LT1789-1/LT1789-10
ELECTRICAL CHARACTERISTICS
VS = ±15V, RL = 20k, VCM = VOUT = 0V, TA = 25°C, unless otherwise noted.
LT1789-1
TYP
LT1789-10
SYMBOL PARAMETER
CONDITIONS
MIN
MAX
MIN
TYP
MAX
UNITS
BW
SR
Bandwidth
G = 1
60
30
3
kHz
kHz
kHz
kHz
G = 10
G = 100
G = 1000
25
12
1.5
0.2
Slew Rate
V
OUT
= ±10V
0.012 0.026
460
0.028 0.066
270
V/µs
µs
Settling Time to 0.01%
Reference Input Resistance
Reference Input Current
Reference Gain to Output
10V Step
R
REFIN
220
220
kΩ
µA
I
V
REF
= 0
2.7
2.7
REFIN
AV
REF
1 ±0.0001
1 ±0.0001
The ● denotes the specifications which apply over the temperature range of 0°C ≤ TA ≤ 70°C. VS = ±15V, RL = 20k, VCM = VREF = 0V,
unless otherwise noted. (Note 4)
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
CONDITIONS
= ±10V
MIN
MAX
MIN
MAX
UNITS
Gain Error
V
O
G = 1
●
●
●
●
0.15
0.38
0.38
0.43
%
%
%
%
G = 10 (Note 2)
G = 100 (Note 2)
G = 1000 (Note 2)
0.20
0.43
0.48
Gain Nonlinearity
V = ±10V
O
G = 1
G = 10
G = 100
G = 1000
●
●
●
●
25
15
25
ppm
ppm
ppm
ppm
45
45
180
120
G/T
Gain vs Temperature
G < 1000 (Notes 2, 3)
●
5
8
50
5
8
50
ppm/°C
V
V
V
V
V
V
V
Total Input Referred Offset Voltage V
= V + V /G
OST OSI OSO
OST
Input Offset Voltage
G = 1000
(Notes 3, 5)
G = 1
●
●
●
●
●
●
●
●
●
●
●
285
30
325
30
µV
µV
OSI
Input Offset Voltage Hysteresis
Output Offset Voltage
OSIH
OSO
OSOH
1.2
120
0.7
5
4
mV
Output Offset Voltage Hysteresis (Notes 3, 5)
50
0.2
1.5
400
0.3
8
1000
0.8
22
µV
/T
Input Offset Voltage Drift (RTI)
Output Offset Voltage Drift
Input Offset Current
(Note 3)
(Note 3)
µV/°C
µV/°C
nA
OSI
/T
OSO
I
I
I
4.5
4.5
OS
/T
Input Offset Current Drift
Input Bias Current
2
2
pA/°C
nA
OS
B
45
14
45
14
I /T
B
Input Bias Current Drift
Input Voltage Range
35
35
pA/°C
V
V
G = 1, Other Input Grounded
1k Source Imbalance,
–14.8
–14.8
CM
CMRR
Common Mode Rejection Ratio
V
G = 1
G = 10
G = 100, 1000
= –14.8V to 14V
CM
●
●
●
78
96
100
dB
dB
dB
91
100
1789f
7
LT1789-1/LT1789-10
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of
0°C ≤ TA ≤ 70°C. VS = ±15V, RL = 20k, VCM = VREF = 0V, unless otherwise noted. (Note 4)
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
PSRR Power Supply Rejection Ratio
CONDITIONS
MIN
MAX
MIN
MAX
UNITS
LT1789-1, V = ±1.25V to ±16V
S
LT1789-10, V = ±1.50V to ±16V
S
G = 1
G = 10
G = 100, 1000
●
●
●
92
102
104
dB
dB
dB
98
104
Minimum Supply Voltage
Supply Current
●
●
●
●
±1.25
±1.50
V
µA
I
150
150
S
V
Output Voltage Swing
Slew Rate
±14.25
±14.25
V
O
SR
V
= ±10V
0.010
0.026
V/µs
OUT
The ● denotes the specifications which apply over the temperature range of –40°C ≤ TA ≤ 85°C. VS = ±15V, RL = 20k, VCM = VREF = 0V,
unless otherwise noted. (Note 4)
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
CONDITIONS
MIN
MAX
MIN
MAX
UNITS
Gain Error
V = ±10V
O
G = 1
●
●
●
●
0.20
0.57
0.57
0.62
%
%
%
%
G = 10 (Note 2)
G = 100 (Note 2)
G = 1000 (Note 2)
0.25
0.62
0.67
Gain Nonlinearity
V = ±10V
O
G = 1
●
●
●
●
30
20
ppm
ppm
ppm
ppm
G = 10
G = 100
G = 1000
50
50
200
30
130
G/T
Gain vs Temperature
G < 1000 (Notes 2, 3)
●
5
8
50
5
8
50
ppm/°C
V
V
V
V
V
V
V
Total Input Referred Offset Voltage V
= V + V /G
OST OSI OSO
OST
Input Offset Voltage
G = 1000
(Notes 3, 5)
G = 1
●
●
●
●
●
●
●
●
●
●
●
305
30
1.3
120
0.7
5
340
30
µV
µV
OSI
Input Offset Voltage Hysteresis
Output Offset Voltage
OSIH
OSO
OSOH
4.2
1000
0.8
22
mV
Output Offset Voltage Hysteresis (Notes 3, 5)
50
0.2
1.5
400
0.3
8
µV
/T
Input Offset Voltage Drift (RTI)
Output Offset Voltage Drift
Input Offset Current
(Note 3)
(Note 3)
µV/°C
µV/°C
nA
OSI
/T
OSO
I
I
I
5
5
OS
/T
OS
Input Offset Current Drift
Input Bias Current
2
2
pA/°C
nA
50
14
50
14
B
I /T
B
Input Bias Current Drift
Input Voltage Range
35
35
pA/°C
V
V
CM
G = 1, Other Input Grounded
1k Source Imbalance,
–14.8
–14.8
CMRR
Common Mode Rejection Ratio
V
= –14.8V to 14V
CM
G = 1
●
●
●
76
94
98
dB
dB
dB
G = 10
G = 100, 1000
89
98
1789f
8
LT1789-1/LT1789-10
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of
–40°C ≤ TA ≤ 85°C. VS = ±15V, RL = 20k, VCM = VREF = 0V, unless otherwise noted. (Note 4)
LT1789-1
TYP
LT1789-10
TYP
SYMBOL PARAMETER
PSRR Power Supply Rejection Ratio
CONDITIONS
LT1789-1, V = ±1.25V to ±16V
MIN
MAX
MIN
MAX
UNITS
S
LT1789-10, V = ±1.50V to ±16V
S
G = 1
●
●
●
90
100
102
dB
dB
dB
G = 10
G = 100, 1000
96
102
Minimum Supply Voltage
Supply Current
●
●
●
●
±1.25
±1.50
V
µA
I
160
160
S
V
Output Voltage Swing
Slew Rate
±14.15
±14.15
V
O
SR
V
= ±10V
0.008
0.024
V/µs
OUT
Note 1: Absolute Maximum Ratings are those values beyond which the life
Note 5: Hysteresis in offset voltage is created by package stress that
of a device may be impaired.
differs depending on whether the IC was previously at a higher or lower
temperature. Offset voltage hysteresis is always measured at 25°C, but
the IC is cycled to 85°C I-grade (or 70°C C-grade) or –40°C I-grade
(0°C C-grade) before successive measurement. 60% of the parts will
pass the typical limit on the data sheet.
Note 2: Does not include the effect of the external gain resistor R .
G
Note 3: This parameter is not 100% tested.
Note 4: The LT1789C-1/ LT1789C-10 is guaranteed to meet specified
performance from 0°C to 70°C and is designed, characterized and
expected to meet these extended temperature limits, but is not tested at
–40°C and 85°C. The LT1789I-1/ LT1789I-10 is guaranteed to meet the
extended temperature limits.
Note 6: V = 5V limits are guaranteed by correlation to V = 3V and
S
S
V = ±15V tests.
S
Note 7: V = 3V limits are guaranteed by correlation to V = 5V and
S
S
V = ±15V tests.
S
Note 8: This parameter is not tested at V = 3V on the LT1789-10 due to
S
an increase in sensitivity to test system noise. Actual performance is
expected to be similar to performance at V = 5V.
S
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-1, LT1789-10)
Input Bias Current
vs Temperature
Input Bias Current
vs Common Mode Input Voltage
Supply Current vs Supply Voltage
120
110
100
90
0
–5
–10
–12
–14
–16
–18
–20
–22
–24
–26
–28
–30
V
V
= 5V, 0V
CM
–55°C
S
= 2.5V
125°C
125°C
80
25°C
85°C
–10
–15
–20
–25
25°C
70
60
–55°C
50
40
V
V
= 5V, 0V
REF
30
S
= 2.5V
20
0
20
30 35
5
10 15
25
40
–50 –25
0
25
50
75 100 125
–0.5 0 0.5
2.5 3
1 4.5 5
1.5 2 3.5 4
TOTAL SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
COMMON MODE INPUT VOLTAGE (V)
1789 G01
1789 G02
1789 G03
1789f
9
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-1)
Output Voltage Swing
vs Load Current
Slew Rate vs Temperature
Gain vs Frequency
80
70
5.0
4.8
4.6
4.4
4.2
4.0
0.050
V
V
= 5V, 0V
S
REF
V
V
= 5V, 0V
= 2.5V
–55°C
S
REF
= 2.5V
0.045
0.040
G = 1000
G = 100
G = 10
125°C
SOURCE
G = 1
= 20k
60
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
R
L
25°C
50
0.035
0.030
0.025
0.020
0.015
40
RISING
V
V
= 5V, 0V
= 2.5V
S
REF
30
125°C
20
25°C
FALLING
10
G = 1
0
SINK
–55°C
–10
–20
0.010
100
1k
10k
100k
–25
0
50
75 100 125
–50
25
0.001
0.01
0.1
1
10
FREQUENCY (Hz)
OUTPUT CURRENT (mA)
TEMPERATURE (°C)
1789 G05
1789 G04
1789 G06
Negative Power Supply Rejection
Ratio vs Frequency
Positive Power Supply Rejection
Ratio vs Frequency
Common Mode Rejection Ratio
vs Frequency
120
110
100
140
120
100
80
140
120
100
80
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
REF
V
V
= 5V, 0V
= 2.5V
REF
S
REF
S
S
= 2.5V
G = 100, 1000
G = 10
INPUT REFERRED
INPUT REFERRED
G = 1000
G =10
G = 1
G = 100
G = 10
G = 100, 1000
G = 1
90
80
G = 1
60
60
70
60
40
40
20
20
50
40
0
0
10
100
1k
10k 20k
10
100
1k
10k 20k
10
100
1k
10k 20k
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
1879 G07
1789 G08
1789 G09
Settling Time to 0.01% vs Output
Step
Output Impedance vs Frequency
Overshoot vs Capacitive Load
100
90
10
8
10k
1k
V
S
= ±15V
= 20k
V
V
= 5V, 0V
= 2.5V
V
V
V
= 5V, 0V
= 2.5V
OUT
S
REF
S
REF
R
L
G = 1
= 100mV
P-P
80
6
70
4
60
50
2
100
10
0
40
30
20
10
0
–2
–4
–6
–8
–10
A
= 1
V
A
= 10
V
A
≥ 100
V
1
100
1
10
100
1000
0
100
300
SETTLING TIME (µs)
400
500
200
1k
10k
100k
FREQUENCY (Hz)
CAPACITIVE LOAD (pF)
1789 G11
1789 G10
1789 G12
1789f
10
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-1)
Voltage Noise Density vs
Frequency
Current Noise Density vs
Frequency
1000
100
10
1000
100
10
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
= 2.5V
S
REF
S
REF
INPUT REFERRED
G = 1
G = 10
R
S
G = 100, 1000
LT1789-1
10
1
10
100
1k
1
100
1k
FREQUENCY (Hz)
FREQUENCY (Hz)
1789 G13
1789 G14
0.1Hz to 10Hz Noise Voltage,
RTI, G = 1000
0.1Hz to 10Hz Noise Voltage,
G = 1
0.1Hz to 10Hz Noise Current
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
= 2.5V
V
= 5V, 0V
= 2.5V
REF
S
REF
S
REF
S
V
0
1
2
3
4
5
6
7
8
9
10
1
3
0
1
2
3
4
5
6
7
8
9
10
0
2
4
5
6
7
8
9 10
TIME (SEC)
TIME (SEC)
TIME (SEC)
1789 G16
1789 G15
1789 G17
Turn-On Characteristics
1.5
0.5
V
V
V
= 5V, 0V
S
= 2.5V
= 2.5V
REF
CM
G = 1000
T
= 25°C
A
–0.5
–1.5
20
0
10
30
40
TIME (ms)
1789 G18
1789f
11
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-10)
Output Voltage Swing
vs Load Current
Gain vs Frequency
Slew Rate vs Temperature
5.0
4.8
4.6
4.4
4.2
4.0
80
70
60
50
40
30
20
10
0
0.12
0.11
0.10
0.09
0.08
0.07
0.06
0.05
0.04
V
V
= 5V, 0V
REF
–55°C
S
= 2.5V
125°C
SOURCE
G = 1000
G = 100
G = 10
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
RISING
25°C
V
V
= 5V, 0V
REF
S
= 2.5V
125°C
FALLING
25°C
SINK
–55°C
–10
–20
0.001
0.01
0.1
1
10
100
1k
10k
100k
–25
0
25
50
75
125
–50
100
OUTPUT CURRENT (mA)
FREQUENCY (Hz)
TEMPERATURE (°C)
1789 G22
1789 G21
1789 G23
Common Mode Rejection Ratio
vs Frequency
Negative Power Supply Rejection
Ratio vs Frequency
Positive Power Supply Rejection
Ratio vs Frequency
140
120
100
80
120
110
100
90
140
120
100
80
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
REF
V
V
= 5V, 0V
= 2.5V
S
REF
S
S
REF
G = 100, 1000
G = 100, 1000
G = 10
= 2.5V
G = 1000
INPUT REFERRED
INPUT REFERRED
G = 10
G = 100
G = 10
80
60
60
70
40
40
60
20
20
50
40
0
0
10
100
1k
10k 20k
10
100
1k
10k 20k
10
100
1k
10k 20k
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
1789 G26
1789 G24
1789 G25
Settling Time to 0.01% vs
Output Step
Output Impedance vs Frequency
Overshoot vs Capacitive Load
10k
1k
100
90
10
8
V
V
= 5V, 0V
= 2.5V
V
S
= ±15V
V
V
V
= 5V, 0V
= 2.5V
OUT
S
REF
S
REF
R
= 20k
L
G = 10
= 100mV
P-P
6
80
70
4
2
60
50
100
10
0
40
30
20
10
0
–2
–4
–6
–8
–10
G = 1000
G = 100
G = 10
1
100
1k
10k
100k
0
100
300
SETTLING TIME (µs)
400
500
200
10
100
CAPACITIVE LOAD (pF)
1000
FREQUENCY (Hz)
1789 G28
1789 G27
1789 G29
1789f
12
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-10)
Current Noise Density vs
Frequency
Voltage Noise Density vs
Frequency
1000
100
10
1000
100
10
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
= 2.5V
S
REF
S
REF
INPUT REFERRED
G = 10
G = 100
G = 1000
R
S
LT1789-10
10
1
100
1k
1
10
100
1k
FREQUENCY (Hz)
FREQUENCY (Hz)
1789 G31
1789 G30
0.1Hz to 10Hz Noise Voltage,
RTI, G = 1000
0.1Hz to 10Hz Noise Voltage,
RTI, G = 10
0.1Hz to 10Hz Noise Current
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
= 2.5V
V
V
= 5V, 0V
= 2.5V
S
REF
S
REF
S
REF
0
1
2
3
4
5
6
7
8
9 10
0
1
2
3
4
5
6
7
8
9 10
0
1
2
3
4
5
6
7
8
9 10
TIME (SEC)
TIME (SEC)
TIME (SEC)
1789 G34
1789 G33
1789 G32
Turn-On Characteristics
1.5
0.5
V
V
V
= 5V, 0V
S
= 2.5V
= 2.5V
REF
CM
G = 1000
T
= 25°C
A
–0.5
–1.5
20
0
10
30
40
TIME (ms)
1789 G18
1789f
13
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-1)
Large-Signal Transient Response
G = 1, 10, 100
Large-Signal Transient Response
G = 1000
1789-1 G38
1789-1 G39
500µs/DIV
VS = ±15V
L = 20k
CL = 50pF
2ms/DIV
VS = ±15V
RL = 20k
CL = 50pF
R
Small-Signal Transient Response
G = 1
Small-Signal Transient Response
G = 10
1789-1 G40
1789-1 G41
100µs/DIV
VS = 5V, 0V
VREF = 2.5V
100µs/DIV
V
V
S = 5V, 0V
REF = 2.5V
R
L = 20k
RL = 20k
CL = 50pF
CL = 50pF
Small-Signal Transient Response
G = 1000
Small-Signal Transient Response
G = 100
1789-1 G43
1789-1 G42
2ms/DIV
VS = 5V, 0V
VREF = 2.5V
RL = 20k
200µs/DIV
VS = 5V, 0V
VREF = 2.5V
RL = 20k
C
L = 50pF
C
L = 50pF
1789f
14
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-10)
Large-Signal Transient Response
G = 10, 100
Large-Signal Transient Response
G = 1000
1789-10 G44
1789-1 0 G45
500µs/DIV
VS = ±15V
500µs/DIV
VS = ±15V
RL = 20k
CL = 50pF
R
L = 20k
CL = 50pF
Small-Signal Transient Response
G = 10
1789-10 G46
100µs/DIV
VS = 5V, 0V
VREF = 2.5V
RL = 20k
C
L = 50pF
Small-Signal Transient Response
G = 100
Small-Signal Transient Response
G = 1000
1789-10 G47
1789-10 G48
200µs/DIV
2ms/DIV
V
V
S = 5V, 0V
REF = 2.5V
V
V
S = 5V, 0V
REF = 2.5V
RL = 20k
RL = 20k
CL = 50pF
CL = 50pF
1789f
15
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-1)
Valid Output Voltage vs Input
Common Mode Voltage
VS = ±15V
Valid Output Voltage vs Input
Common Mode Voltage
VS = ±2.5V
Valid Output Voltage vs Input
Common Mode Voltage
VS = ±1.5V
15
10
5
3.0
2.5
1.5
1.0
T
= 25°C
T
= 25°C
A
A
T = 25°C
A
A
V
= 10
G ≥ 2
G = 1
A
= 1
= 2
V
2.0
A
= 1
V
A
V
A = 10
1.5
A
= 2
V
V
0.5
1.0
0.5
0
0
0
–0.5
–1.0
–1.5
–2.0
–2.5
–5
–10
–15
–0.5
–1.0
–1.5
–15
–5
0
5
10
15
–10
–2.5
–1.5
–0.5
0.5
1.5
2.5
–1.5
–0.5
0
0.5
1.0
1.5
–1.0
INPUT COMMON MODE VOLTAGE (V)
INPUT COMMON MODE VOLTAGE (V)
INPUT COMMON MODE VOLTAGE (V)
15V
2.5V
1.5V
+
+
+
+
+
+
V
V
V
V /2
D
V /2
D
V /2
D
V
V
V
LT1789-1
LT1789-1
LT1789-1
OUT
OUT
OUT
V /2
D
V /2
D
V /2
D
REF
REF
REF
20K
20K
20K
V
CM
V
CM
V
CM
–
–
–
V
–
–
–
V
V
1789 G49
–15V
–2.5V
–1.5V
1789 G50
1789 G51
Valid Output Voltage vs Input
Common Mode Voltage
VS = 5V
Valid Output Voltage vs Input
Common Mode Voltage
VS = 3V
5
4
3
2
1
0
3
T
= 25°C
T = 25°C
A
A
2
1
0
G = 1
G = 1
G = 2
G = 10
G = 2
G = 10
0
1
2
3
4
5
2.0
3.0
0
0.5
1.5
2.5
1.0
INPUT COMMON MODE VOLTAGE (V)
INPUT COMMON MODE VOLTAGE (V)
5V
3V
+
+
+
+
V
V
V /2
D
V /2
D
V
V
LT1789-1
LT1789-1
OUT
OUT
V /2
D
V /2
D
REF
REF
20K
20K
V
V
CM
CM
–
–
V
–
–
V
1789 G52
1789 G53
1789f
16
LT1789-1/LT1789-10
U W
TYPICAL PERFOR A CE CHARACTERISTICS
(LT1789-10)
Valid Output Voltage vs Input
Common Mode Voltage
VS = ±15V
Valid Output Voltage vs Input
Common Mode Voltage
VS = ±2.5V
Valid Output Voltage vs Input
Common Mode Voltage
VS = ±1.5V
15
10
5
2.5
2.0
1.5
G = 10
T
= 25°C
T = 25°C
A
A
A
V
= 10
T
= 25°C
A
A
V
= 10
G = 100
1.0
0.5
A
V
= 100
1.5
A
V
= 100
1.0
0.5
0
0
0
–0.5
–1.0
–1.5
–2.0
–2.5
–5
–10
–15
–0.5
–1.0
–1.5
–15
–5
0
5
10
15
0
–0.5
–10
–2.5
–1.5
0.5
1.5
2.5
–1.5
–0.5
0
0.5
1.0
1.5
–1.0
INPUT COMMON MODE VOLTAGE (V)
INPUT COMMON MODE VOLTAGE (V)
INPUT COMMON MODE VOLTAGE (V)
15V
2.5V
1.5V
+
+
+
+
+
+
V
V
V
V /2
D
V /2
D
V /2
D
V
V
V
LT1789-10
LT1789-10
LT1789-10
OUT
OUT
OUT
V /2
D
V /2
D
V /2
D
REF
REF
REF
20K
20K
20K
V
CM
V
CM
V
CM
–
–
–
–
–
–
V
V
V
–15V
–2.5V
–1.5V
1789 G54
1789 G55
1789 G56
Valid Output Voltage vs Input
Common Mode Voltage
VS = 5V
Valid Output Voltage vs Input
Common Mode Voltage
VS = 3V
5
4
3
2
1
0
3
2
1
0
T
= 25°C
A
T
= 25°C
A
G = 10
G = 10
G = 100
G = 100
0
1
2
3
4
5
2.0
3.0
0
0.5
1.5
2.5
1.0
INPUT COMMON MODE VOLTAGE (V)
INPUT COMMON MODE VOLTAGE (V)
5V
3V
+
+
+
+
V
V
V /2
D
V /2
D
V
V
LT1789-10
LT1789-10
OUT
OUT
V /2
D
V /2
D
REF
REF
20K
20K
V
V
CM
CM
–
–
–
–
V
V
1789 G57
1789 G58
1789f
17
LT1789-1/LT1789-10
W
BLOCK DIAGRA
+
+
V
V
100k
+
V
5.7k
+IN
3
–
+
R1
R2
R
1
8
G
110k/10k* 110k/100k*
A1
5
REF
–
+
–
+
V
V
V
V
V
B
–
V
+
A3
R
G
100k
+
–
V
5.7k
–IN
2
–
+
R3
R4
110k/10k* 110k/100k*
A2
6
7
OUT
–
–
V
V
+
V
–
V
B
V
*LT1789-1/LT1789-10
–
4
V
1789 BD
Figure 1. Block Diagram
1789f
18
LT1789-1/LT1789-10
W U U
APPLICATIO S I FOR ATIO
U
Setting the Gain
voltage dominates, whereas at low gains the output offset
voltage dominates. The total offset voltage is:
The gain of the LT1789-1 and LT1789-10 is set by the
value of resistor RG, applied across pins 1 and 8. For the
LT1789-1, the gain G will be:
Total input offset voltage (RTI)
= input offset + (output offset/G)
G = 1+ 200k/RG
Total output offset voltage (RTO)
= (input offset • G) + output offset
and RG can be calculated from the desired gain by
RG = 200k/(G – 1)
Reference Terminal
For the LT1789-10, the gain G will be
G =10 • (1 + 200k/RG)
The output voltage of the LT1789-1/LT1789-10 (Pin 6) is
referenced to the voltage on the reference terminal (Pin
5). Resistance in series with the REF pin must be mini-
mized for best common mode rejection. For example, a
22Ω resistance from the REF pin to ground will not only
increase the gain error by 0.02% but will lower the CMRR
to 80dB.
and RG can be calculated from the desired gain by
RG = 200k/(0.1 • G – 1)
For the lowest achievable gain, RG may be set to infinity by
leaving Pins 1 and 8 open.
Output Offset Trimming
Input and Output Offset Voltage
The LT1789-1/LT1789-10 is laser trimmed for low offset
voltage so that no external offset trimming is required for
most applications. In the event that the offset needs to be
adjusted,thecircuitinFigure2isanexampleofanoptional
offset adjust circuit. The op amp buffer provides a low
impedance to the REF pin where resistance must be kept
to a minimum for best CMRR and lowest gain error.
The offset voltage of the LT1789-1/LT1789-10 has two
components: the output offset and the input offset. The
total offset voltage referred to the input (RTI) is found by
dividingtheoutputoffsetbytheprogrammedgain(G)and
adding it to the input offset. At high gains the input offset
–
2
+
V
OUTPUT
6
–IN
1
8
3
R
G
LT1789-1/-10
REF
–
2
3
10mV
+
+IN
5
1
100Ω
10k
LT1880
+
±10mV
ADJUSTMENT RANGE
100Ω
–10mV
–
V
1789 F02
Figure 2. Optional Trimming of Output Offset Voltage
1789f
19
LT1789-1/LT1789-10
W U U
U
APPLICATIO S I FOR ATIO
Input Bias Current Return Path
Output Voltage vs Input Common Mode Voltage
The low input bias current of the LT1789-1/LT1789-10
(19nA) and the high input impedance (1.6GΩ) allow the
use of high impedance sources without introducing sig-
nificant offset voltage errors, even when the full common
moderangeisrequired.However,apathmustbeprovided
for the input bias currents of both inputs when a purely
differential signal is being amplified. Without this path the
inputs will float high and exceed the input common mode
rangeoftheLT1789-1/LT1789-10,resultinginasaturated
input stage. Figure 3 shows three examples of an input
bias current path. The first example is of a purely differen-
tial signal source with a 10kΩ input current path to
ground. Since the impedance of the signal source is low,
only one resistor is needed. Two matching resistors are
needed for higher impedance signal sources as shown in
the second example. Balancing the input impedance im-
proves both common mode rejection and DC offset. The
need for input resistors is eliminated if a center tap is
present as shown in the third example.
All instrumentation amplifiers have limiting factors that
can cause an output to be invalid (the output is not equal
totheinputdifferentialvoltagemultipliedbythegain)even
though the output appears to be operating in a linear
region. Limiting factors such as input voltage range and
output swing can be easily measured, however, there are
also internal nodes that can limit. These internal nodes
cannot be measured externally and can lead to erroneous
output readings.
To ensure a valid output for a given input common mode
voltage and input differential voltage, the following four
limiting factors must be taken into consideration (refer to
the block diagram):
1) The input voltage ranges of the input amplifiers A1 and
A2.
2) The output swings of the input amplifiers A1 and A2
(internal nodes).
–
–
+
–
+
MICROPHONE,
LT1789-1/
LT1789-1/
LT1789-10
LT1789-1/
LT1789-10
R
HYDROPHONE,
ETC
R
G
R
G
THERMOCOUPLE
G
LT1789-10
+
200k
200k
10k
CENTER-TAP PROVIDES
BIAS CURRENT RETURN
1789 F03
Figure 3. Providing an Input Common Mode Current Path
1789f
20
LT1789-1/LT1789-10
W
U U
U
APPLICATIO S I FOR ATIO
single supplies, where both the reference voltage and
inputcommonmodevoltagearenearV+. Thisisalsomore
of a concern with the LT1789-10 because the ratio of
R1:R2 is 1:10 instead of 1:1.
3) The input voltage range of the output amplifier A3
(internal node).
4) The output swing of the output amplifier A3.
These limits can be determined using the relationships
below.
4)The output voltage swing limits are also found in the
electrical tables.
1)The input voltage range limits can be found in the
electrical tables.
The Output Voltage vs Input Common Mode Voltage
typical performance curves show the regions of operation
for the three supply voltages specified.
2)The output voltages of the input amplifiers A1 and A2
can be found by the following formulas:
Single Supply Operation
V
OUT A1 = (VD/2)(G)(R1/R2) + VCM + 0.6V
There are usually two types of input signals that need to be
processed; differential signals, like the output of a bridge
or single ended signals, such as the output from a ther-
mistor. Both signals require special consideration when
operating with a single supply.
VOUT A2 = (–VD/2)(G)(R1/R2) + VCM + 0.6V
Where VD is the input differential voltage and VCM is the
input common mode voltage.
The typical output swing limits for A1 and A2 can be found
in the Output Swing vs Load Current typical performance
curve, using R1 + R2 as the load resistance.
When processing differential signals , REF (Pin 5) must be
brought above the negative supply (Pin 4) to allow the
output to process both the positive and negative going
input signal. The maximum output operating range is
obtained by setting the voltage on the REF pin to half
supply. Thismustbedonewithalowimpedancesourceto
minimize CMRR and gain errors.
This limitation usually becomes dominant when gain is
taken in the input stage and the common mode input
voltage is close to either supply rail.
The LT1789-10 is less susceptible to this limiting factor
because the gain is taken in the output stage.
For single ended input signals, the REF pin can be at the
same potential as the negative supply provided the output
of the instrumentation amplifier remains inside the speci-
fied operating range. This maximizes the output range,
however the smallest input signal that can be processed is
limited by the output swing to the negative supply.
3)The voltage on the inputs to the output amplifier A3 can
be determined by the following formula:
VIN A3 = (VOUT A1 – VREF)(R2/(R1 + R2))
The input voltage range of A3 has the same input limits as
the LT1789-1. This limiting factor is more prevalent with
1789f
21
LT1789-1/LT1789-10
U
TYPICAL APPLICATIO S
Single Supply Positive Integrator
V
S
3
V
+
IN
7
V
S
R1
10k
8
6
3
4
LT1789-1
REF
+
–
1
2
1
+
V
OUT
LT1636
2
5
C1
R2
100µF 10Ω
–
4
RESET
1789 TA02
V
S
= 2.7V TO 32V
TIME CONSTANT = (R1)(C1) = 1 SECOND AS SHOWN
Avalanche Photo Diode Module Bias Current Monitor
FOR OPTIONAL “ZERO CURRENT” FEEDBACK TO
APD BIAS REGULATOR, SEE APPENDIX A, APPLICATION NOTE 92
1k*
1%
APD
HIGH VOLTAGE
BIAS INPUT
V
= 20V TO 90V
OUT
TO APD
1µF
100V
1µF
100V
100k*
100k*
Q1
1N4690
5.6V
1M*
0.2µF
5V
5V
6
–
1µF
+
–
20k
2
A1
OUTPUT
0V TO 1V =
0mA TO 1mA
S2
A2
LT1006
LT1789-1
+
10k
1µF
30k
5
0.2µF
Q2
MPSA42
20k*
–3.5V
1M*
–3.5V
20k
13
200k*
18
12
14
S1
–3.5V TO
AMPLIFIERS
5V
22µF
5V
3
S3
15
* = 0.1% METAL FILM RESISTOR
22µF
+
1µF 100V = TECATE CMC100105MX1825
CIRCLED NUMBERS = LTC1043 PIN NUMBER
#
= 1N4148
16
17
4
= TP0610L
0.056µF
5V
†
FOR MORE INFORMATION REFER TO APPLICATION NOTE 92
AN92 F04
1789f
22
LT1789-1/LT1789-10
U
PACKAGE DESCRIPTION
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
.189 – .197
(4.801 – 5.004)
.045 ±.005
.160 ±.005
NOTE 3
.050 BSC
7
5
8
6
.245
MIN
.150 – .157
(3.810 – 3.988)
NOTE 3
.228 – .244
(5.791 – 6.197)
.030 ±.005
TYP
1
3
4
2
RECOMMENDED SOLDER PAD LAYOUT
.010 – .020
(0.254 – 0.508)
× 45°
.053 – .069
(1.346 – 1.752)
.004 – .010
(0.101 – 0.254)
.008 – .010
(0.203 – 0.254)
0°– 8° TYP
.016 – .050
(0.406 – 1.270)
.050
(1.270)
BSC
.014 – .019
(0.355 – 0.483)
TYP
NOTE:
INCHES
1. DIMENSIONS IN
(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)
SO8 0303
1789f
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 represen-
tationthattheinterconnectionofitscircuitsasdescribedhereinwillnotinfringeonexistingpatentrights.
23
LT1789-1/LT1789-10
U
TYPICAL APPLICATIO S
Voltage Controlled Current Source
3V TO 32V
3
V
+
IN
7
8
6
L
LT1789-1
R
G
REF
1
2
R1
1k
5
–
4
I
LOAD
I
= A • V /R1
L
V
IN
1789 TA03
200k
G
A
V
= 1 +
R
10°C to 40°C Thermometer
29.4k
1%
+
V
S
4
6
3
8
+
LT1790
–1.25
V
S
+
–
7
1
2
6
36.5k
0.5%
LT1789-10
4
1
2
V
= 2.5V AT 25°C + 50mV/°C
OUT
5
OVER 10°C TO 40°C
LINEARITY = 0.3°C
THERMISTOR
THERMOMETRICS
DC95G104V
100k
@ 25°C
866k
1%
ACCURACY = 1°C WORST CASE
TOLERANCE STACK-UP
56.2k
1%
+
V
S
= 4V TO 18V
1789 TA04
RELATED PARTS
PART NUMBER DESCRIPTION
COMMENTS
LTC1100
LT1101
LT1102
LT1167
Precision Chopper-Stabilized Instrumentation Amplifier
Best DC Accuracy
Precision, Micropower, Single Supply Instrumentation Amplifier
High Speed, JFET Instrumentation Amplifier
Fixed Gain of 10 or 100, I < 105µA
S
Fixed Gain of 10 or 100, 30V/µs Slew Rate
Single Resistor Gain Programmable,
Precision Instrumentation Amplifier
Gain Error: 0.08% Max, Gain Nonlinearity: 10ppm Max,
60µV Max Input Offset Voltage, 90dB Min CMRR
LT1168
LTC®1418
Low Power, Single Resistor Programmable Instrumentation Amplifier
14-Bit, Low Power, 200ksps ADC with Serial and Parallel I/O
I
= 530µA Max
SUPPLY
Single Supply 5V or ±5V Operation, ±1.5LSB INL
and ±1LSB DNL Max
LT1460
LT1468
Precision Series Reference
Micropower; 2.5V, 5V, 10V Versions; High Precision
16-Bit Accurate Op Amp, Low Noise Fast Settling
16-Bit Accuracy at Low and High Frequencies, 90MHz GBW,
22V/µs, 900ns Settling
LTC1562
LTC1605
Active RC Filter
Lowpass, Bandpass, Highpass Responses; Low Noise,
Low Distortion, Four 2nd Order Filter Sections
16-Bit, 100ksps, Sampling ADC
Single 5V Supply, Bipolar Input Range: ±10V,
Power Dissipation: 55mW Typ
1789f
LT/TP 0403 2K • PRINTED IN USA
24 LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
●
●
(408) 432-1900 FAX: (408) 434-0507 www.linear.com
LINEAR TECHNOLOGY CORPORATION 2002
相关型号：
LT1789CS8-1#PBF
LT1789 - Micropower, Single Supply Rail-to-Rail Output Instrumentation Amplifier; Package: SO; Pins: 8; Temperature Range: 0°C to 70°C
Linear
LT1789CS8-1#TRPBF
LT1789 - Micropower, Single Supply Rail-to-Rail Output Instrumentation Amplifier; Package: SO; Pins: 8; Temperature Range: 0°C to 70°C
Linear
©2020 ICPDF网 联系我们和版权申明