LT1494/LT1495/LT1496
1.5µA Max, Single, Dual
and Quad Over-The-Top Precision
Rail-to-Rail Input and Output Op Amps
U
FEATURES
■
■
■
■
■
■
■
■
■
■
■
■
DESCRIPTIO
Low Supply Current: 1.5µA Max
Rail-to-Rail Input and Output
Low Offset Voltage: 375µV Max
Operating Temperature Range: – 40°C to 125°C
Over-The-TopTM Inputs Operate Above V+
Wide Supply Range: 2.2V to 36V
Single Supply Input Range: – 0.3V to 36V
Low Input Bias Current: 250pA
Low Input Offset Current: 20pA
High AVOL: 100V/mV Minimum Driving 100kΩ Load
Output Sources and Sinks 500µA Load Current
Reverse Battery Protected to 18V
The LT®1494/LT1495/LT1496 are the lowest power
(IS ≤ 1.5µA) op amps with precision specifications. The
extremely low supply current is combined with excellent
amplifier specifications: input offset voltage is 375µV
maximum with a typical drift of only 0.4µV/°C, input offset
current is 100pA maximum. A minimum open-loop gain
(AVOL) of 100V/mV ensures that gain errors are small. The
device characteristics change little over the supply range
of 2.2V to ±15V. Supply rejection is 90dB and the common
mode rejection ratio is 90dB. Operation is specified for 3V,
5V and ±15V supplies. Reverse battery protection
(–18V␣ min) and inputs that operate above the positive
supply make the LT1494/LT1495/LT1496 easy to use in
harsh environments.
U
APPLICATIO S
■
■
■
■
The low bias currents and offset current of the amplifier
permit the use of megohm level source resistors without
introducing significant errors. Voltage noise at 4µVP-P is
remarkably low considering the low supply current.
Battery- or Solar-Powered Systems
Portable Instrumentation
Remote Sensor Amplifier
Micropower Filter
The LT1494 is available in the 8-Pin MSOP, PDIP and SO
packages.The LT1495 is available in plastic 8-Pin PDIP
and SO packages with the standard dual op amp pinout.
The LT1496 is available in 14-Pin SO and PDIP packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Over-The-Top is a trademark of Linear Technology Corporation.
U
TYPICAL APPLICATION
Micropower Integrating Current Sense
RI
1M
30
0.1µF
25
RS
0.1Ω 1M
1/2 LT1495
–
+
1/2 LT1495
IL
LOAD
10M
15
VO
10
+
5
10M
1495 TA01
VCC
200k
OUTPUT SWITCHES
WHEN ILdt = 0.98 VCC
100 AMPLIFIERS
VS = ±2.5V
–40°C TO 85°C
20
–
UNITS
VCC
TC VOS Distribution
RESET
( )
0
– 2.0 –1.6 –1.2 –0.8 –0.4 0 0.4 0.8 1.2 1.6 2.0
TC VOS (µV/°C)
1495 TA02
RI
C = (4.9A)(SEC) FOR VCC = 5V
RS
IS = 3µA DURING INTEGRATION; IS = 5µA END OF INTEGRATION
1
LT1494/LT1495/LT1496
U
W W
W
ABSOLUTE MAXIMUM RATINGS (Note 1)
Total Supply Voltage (V + to V –) .............................. 36V
Differential Input Voltage ......................................... 36V
Input Current ...................................................... ±10mA
Output Short-Circuit Duration ....................... Continuous
Operating Temperature Range (Note 2)
LT1494C/LT1495C/LT1496C .............. – 40°C to 85°C
LT1494I/LT1495I/LT1496I ................. – 40°C to 85°C
LT1494H/LT1495H/LT1496H ........... – 40°C to 125°C
Specified Temperature Range (Note 3)
LT1494C/LT1495C/LT1496C .............. – 40°C to 85°C
LT1494I/LT1495I/LT1496I ................. – 40°C to 85°C
LT1494H/LT1495H/LT1496H ........... – 40°C to 125°C
Storage Temperature Range ................. – 65°C to 150°C
Junction Temperature ........................................... 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
U
W
U
PACKAGE/ORDER INFORMATION
ORDER PART
NUMBER
TOP VIEW
NC
–IN
+IN
V–
8 NC
7 V+
6 OUT
5 NC
1
2
3
4
LT1494CMS8
LT1494IMS8
MS8 PACKAGE
8-LEAD PLASTIC MSOP
TJMAX = 150°C, θJA = 250°C/ W
MS8 PART MARKING
LTFF
LTFG
NC 1
8
NC
–IN 2
7
V+
+IN 3
6
OUT
V– 4
5
NC
N8 PACKAGE
8-LEAD PDIP
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 130°C/ W (N8)
TJMAX = 150°C, θJA = 190°C/ W (S8)
ORDER PART
NUMBER
TOP VIEW
OUT A 1
8
–IN A 2
A
+IN A 3
V– 4
N8 PACKAGE
8-LEAD PDIP
V+
7
OUT B
6
–IN B
5
+IN B
B
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 130°C/ W (N8)
TJMAX = 150°C, θJA = 190°C/ W (S8)
LT1495CN8
LT1495CS8
LT1495IN8
LT1495IS8
LT1495HS8
S8 PART MARKING
1495
1495I
1495H
Consult LTC Marketing for parts specified with wider operating temperature ranges.
2
ORDER PART
NUMBER
TOP VIEW
LT1494CN8
LT1494CS8
LT1494IN8
LT1494IS8
LT1494HS8
S8 PART MARKING
1494
1494I
1494H
ORDER PART
NUMBER
TOP VIEW
OUT A
1
–IN A
2
+IN A
3
12 +IN D
V+
4
11 V –
+IN B
5
–IN B
6
OUT B
7
14 OUT D
A
D
13 –IN D
10 +IN C
B
N PACKAGE
14-LEAD PDIP
C
9
–IN C
8
OUT C
S PACKAGE
14-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 130°C/ W (N)
TJMAX = 150°C, θJA = 160°C/ W (S)
LT1496CN
LT1496CS
LT1496IN
LT1496IS
LT1496HS
LT1494/LT1495/LT1496
ELECTRICAL CHARACTERISTICS
TA = 25°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half supply, unless otherwise noted.
SYMBOL PARAMETER
Input Offset Voltage
VOS
IB
Input Bias Current
IOS
en
in
AVOL
Input Offset Current
Input Noise Voltage
Input Noise Voltage Density
Input Noise Current Density
Large-Signal Voltage Gain
CMRR
Input Voltage Range
Common Mode Rejection Ratio
PSRR
VOL
Power Supply Rejection Ratio
Minimum Operating Supply Voltage
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
Reverse Supply Voltage
Slew Rate
Gain Bandwidth Product
SR
GBW
CONDITIONS
VS = 5V
VS = 3V
VS = 5V, MS8 Package
VS = 3V, MS8 Package
(Note 5)
VCM = 10V (Note 6)
(Note 5)
0.1Hz to 10Hz
f = 100Hz
f = 100Hz
VS = 5V, VO = 0.25V to 4.5V, RL = 100k
VS = 3V, VO = 0.25V to 2.5V, RL = 100k
VCM = 0V to 4V, VS = 5V
VCM = 0V to 10V, VS = 5V
VS = 2.2V to 12V, VCM = VO = 0.5V
No Load
ISINK = 100µA
No Load
ISOURCE = 100µA
(Note 5)
(Note 6)
IS = 10µA per Amplifier
AV = –1, VS = ±5V
f = 100Hz
MIN
100
50
0
90
74
90
V+ – 0.07
V+ – 0.32
0.7
–18
0.4
TYP
150
200
150
200
250
180
20
4
185
10
500
250
MAX
375
475
475
575
1000
360
100
36
106
95
99
2.1
50
210
V+ – 0.035
V+ – 0.160
1.3
1.0
1.0
2.7
2.2
100
410
1.5
UNITS
µV
µV
µV
µV
pA
nA
pA
µVP-P
nV/√Hz
fA/√Hz
V/mV
V/mV
V
dB
dB
dB
V
mV
mV
V
V
mA
µA
V
V/ms
kHz
3
LT1494/LT1495/LT1496
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of 0°C ≤ TA ≤ 70°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half
supply, unless otherwise noted. (Note 3)
SYMBOL PARAMETER
Input Offset Voltage
VOS
VOS TC
IB
Input Offset Voltage Drift
Input Bias Current
IOS
AVOL
Input Offset Current
Large-Signal Voltage Gain
CMRR
Input Voltage Range
Common Mode Rejection Ratio
PSRR
VOL
Power Supply Rejection Ratio
Minimum Operating Supply Voltage
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
CONDITIONS
VS = 5V
VS = 3V
VS = 5V, MS8 Package
VS = 3V, MS8 Package
(Note 4)
(Note 5)
VCM = 10V (Note 6)
(Note 5)
VS = 5V, VO = 0.25V to 4.5V, RL = 100k
VS = 3V, VO = 0.25V to 2.5V, RL = 100k
MIN
●
●
●
●
●
●
●
●
●
●
●
VCM = 0.2V to 4V, VS = 5V
VCM = 0.2V to 10V, VS = 5V
VS = 2.4V to 12V, VCM = VO = 0.5V
●
●
●
75
40
0.2
89
64
89
●
No Load
ISINK = 100µA
No Load
ISOURCE = 100µA
(Note 5)
(Note 6)
●
●
●
●
●
V+ – 0.08
V+ – 0.36
0.6
●
TYP
175
225
175
225
0.4
250
240
20
280
150
MAX
425
525
525
625
2
1200
500
120
36
106
85
99
2.3
55
225
V+ – 0.04
V+ – 0.18
1.1
1.2
2.4
110
450
1.8
UNITS
µV
µV
µV
µV
µV/°C
pA
nA
pA
V/mV
V/mV
V
dB
dB
dB
V
mV
mV
V
V
mA
µA
The ● denotes the specifications which apply over the temperature range of – 40°C ≤ TA ≤ 85°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO =
half supply, unless otherwise noted. (Note 3)
SYMBOL PARAMETER
Input Offset Voltage
VOS
VOS TC
IB
Input Offset Voltage Drift
Input Bias Current
IOS
AVOL
Input Offset Current
Large-Signal Voltage Gain
CMRR
Input Voltage Range
Common Mode Rejection Ratio
PSRR
VOL
Power Supply Rejection Ratio
Minimum Operating Supply Voltage
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
4
CONDITIONS
VS = 5V
VS = 3V
VS = 5V, MS8 Package
VS = 3V, MS8 Package
(Note 4)
(Note 5)
VCM = 10V (Note 6)
(Note 5)
VS = 5V, VO = 0.25V to 4.5V, RL = 100k
VS = 3V, VO = 0.25V to 2.5V, RL = 100k
MIN
●
●
●
●
●
●
●
●
●
●
●
VCM = 0.2V to 4V, VS = 5V
VCM = 0.2V to 10V, VS = 5V
VS = 2.7V to 12V, VCM = VO = 0.5V
●
●
●
55
30
0.2
88
88
●
No Load
ISINK = 100µA
No Load
ISOURCE = 100µA
(Note 5)
(Note 6)
●
●
●
●
●
●
V+ – 0.10
V+ – 0.38
0.4
TYP
200
250
200
250
0.4
250
275
20
215
115
MAX
475
575
575
675
2
1700
170
36
106
75
99
2.6
60
245
V+ – 0.05
V+ – 0.19
0.9
1.5
2.7
120
490
2.3
UNITS
µV
µV
µV
µV
µV/°C
pA
nA
pA
V/mV
V/mV
V
dB
dB
dB
V
mV
mV
mV
mV
mA
µA
LT1494/LT1495/LT1496
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of – 40°C ≤ TA ≤ 125°C. VS = 5V, 0V; VS = 3V, 0V; VCM = VO =
half supply, unless otherwise noted. (Note 3)
SYMBOL PARAMETER
Input Offset Voltage
VOS
VOS TC
IB
Input Offset Voltage Drift
Input Bias Current
IOS
AVOL
Input Offset Current
Large-Signal Voltage Gain
CMRR
Input Voltage Range
Common Mode Rejection Ratio
PSRR
VOL
Power Supply Rejection Ratio
Minimum Operating Supply Voltage
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
IS
Supply Current per Amplifier
CONDITIONS
VS = 5V
VS = 3V
(Note 4)
(Note 5)
VCM = 10V (Note 6)
(Note 5)
VS = 5V, VO = 0.25V to 4.5V, RL = 100k
VS = 3V, VO = 0.25V to 2.5V, RL = 100k
●
●
●
●
●
●
●
●
●
VCM = 0.5V to 4V, VS = 5V
VCM = 0.5V to 10V, VS = 5V
VS = 2.7V to 12V, VCM = VO = 0.5V
●
●
●
●
No Load
ISINK = 100µA
No Load
ISOURCE = 100µA
(Note 6)
LT1494H/LT1495H/LT1496H
TYP
MAX
225
875
275
975
0.4
3
3.8
10
0.300
2
0.3
2
4
25
2
17
0.5
36
72
95
85
86
105
2.7
70
160
275
550
V+ – 140
V+ – 45
V+ – 450
V+ – 225
2
5
MIN
●
●
●
●
●
UNITS
µV
µV
µV/°C
nA
µA
nA
V/mV
V/mV
V
dB
dB
dB
V
mV
mV
mV
mV
µA
TA = 25°C, VS = ±15V, VCM = VO = 0V, unless otherwise noted.
SYMBOL PARAMETER
VOS
Input Offset Voltage
CONDITIONS
MIN
MS8 Package
IB
IOS
AVOL
CMRR
PSRR
VOL
Input Bias Current
Input Offset Current
Large-Signal Voltage Gain
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
VO = ±10V, RL = 100k
VCM = – 15V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
100
– 15
100
96
14.78
14.62
0.7
TYP
200
200
25
20
360
MAX
575
675
1000
100
21
120
120
–14.85
–14.75
14.89
14.81
1.5
1.4
–14.70
–14.50
2.0
UNITS
µV
µV
pA
pA
V/mV
V
dB
dB
V
V
V
V
mA
µA
5
LT1494/LT1495/LT1496
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of 0°C ≤ TA ≤ 70°C, VS = ±15V, VCM = VO = 0V, unless
otherwise noted. (Note 3)
SYMBOL PARAMETER
VOS
Input Offset Voltage
CONDITIONS
MS8 Package
IB
IOS
AVOL
CMRR
PSRR
VOL
Input Bias Current
Input Offset Current
Large-Signal Voltage Gain
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
MIN
●
●
●
●
VO = ±10V, RL = 100k
●
●
VCM = –14.8V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
●
●
60
– 14.8
98
94
●
●
●
●
●
14.76
14.58
0.6
●
TYP
225
225
250
20
240
MAX
625
725
1200
120
21
120
120
–14.84
–14.73
14.88
14.79
1.3
1.6
–14.67
–14.46
2.4
UNITS
µV
µV
pA
pA
V/mV
V
dB
dB
V
V
V
V
mA
µA
The ● denotes the specifications which apply over the temperature range of –40°C ≤ TA ≤ 85°C, VS = ±15V, VCM = VO = 0V, unless
otherwise noted. (Note 3)
SYMBOL PARAMETER
VOS
Input Offset Voltage
CONDITIONS
MS8 Package
IB
IOS
AVOL
CMRR
PSRR
VOL
Input Bias Current
Input Offset Current
Large-Signal Voltage Gain
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
6
MIN
●
●
●
●
VO = ±10V, RL = 100k
●
●
VCM = –14.8V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
●
●
50
– 14.8
96
92
●
●
●
●
●
●
14.74
14.54
0.4
TYP
250
250
250
20
200
MAX
675
775
1700
170
21
114
120
–14.83
–14.72
14.87
14.77
1.1
2.0
–14.66
–14.44
3.0
UNITS
µV
µV
pA
pA
V/mV
V
dB
dB
V
V
V
V
mA
µA
LT1494/LT1495/LT1496
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range of –40°C ≤ TA ≤ 125°C. VS = ±15V, VCM = VO = half supply,
unless otherwise noted. (Note 3)
SYMBOL
VOS
IB
IOS
AVOL
CMRR
PSRR
VOL
PARAMETER
Input Offset Voltage
Input Bias Current
Input Offset Current
Large-Signal Voltage Gain
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing LOW
VOH
Output Voltage Swing HIGH
IS
Supply Current per Amplifier
LT1494H/LT1495H/LT1496H
TYP
MAX
275
1100
3.8
10
0.3
2
21
70
–14.5
21
69
90
89
115
–14.80
–14.4
–14.69
–14.2
14.5
14.85
14.3
14.73
3
6
CONDITIONS
MIN
●
●
●
VO = ±10V, RL = 100k
●
●
VCM = –14.5V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
●
●
●
●
●
●
●
UNITS
µV
nA
nA
V/mV
V
dB
dB
V
V
V
V
µA
–40°C to 85°C but are not tested or QA sampled at these temperatures.
The LT1494I/LT1495I/LT1496I are guaranteed to meet specified
performance from –40°C to 85°C. The LT1494H/LT1495H/LT1496H are
guaranteed to meet specified performance from –40°C to 125°C.
Note 4: This parameter is not 100% tested.
Note 5: VS = 5V limits are guaranteed by correlation to VS = 3V and
VS = ±15V tests.
Note 6: VS = 3V limits are guaranteed by correlation to VS = 5V and
VS = ±15V tests.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2: The LT1494C/LT1495C/LT1496C and LT1494I/LT1495I/LT1496I
are guaranteed functional over the operating temperature range of – 40°C
to 85°C. The LT1494H/LT1495H/LT1496H are guaranteed functional over
the operating temperature range of –40°C to 125°C.
Note 3: The LT1494C/LT1495C/LT1496C are guaranteed to meet specified
performance from 0°C to 70°C. The LT1494C/LT1495C/LT1496C are
designed, characterized and expected to meet specified performance from
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Distribution of Input Offset Voltage
PERCENT OF UNITS (%)
16
VS = 5V, 0V
LT1494/LT1495/
LT1496
5700 OP AMPS
14
12
10
8
6
4
2
0
–400 –300 –200 –100 0 100 200 300 400
INPUT OFFSET VOLTAGE (µV)
1495 G01
Minimum Supply Voltage
200
CHANGE IN OFFSET VOLTAGE (µV)
18
Supply Current vs Temperature
2.5
SUPPLY CURRENT PER AMPLIFIER (µA)
20
2.0
1.5
VS = ±15V
1.0
VS = ±2.5V
0.5
0
– 40 – 20
150
TA = 25°C
TA = – 40°C
100
TA = 85°C
50
0
– 50
40
20
0
60
TEMPERATURE (°C)
80
100
1495 G02
1
3
2
4
TOTAL SUPPLY VOLTAGE (V)
5
1495 G03
7
LT1494/LT1495/LT1496
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Output Saturation Voltage
vs Load Current (Output Low)
TA = 85°C
100
TA = 25°C
TA = – 40°C
10
0.1
1
10
100
LOAD CURRENT (µA)
100
TA = 85°C
TA = 25°C
TA = – 40°C
10
0.1
1000
300
VS = 5V, 0V
1
10
100
LOAD CURRENT (µA)
1495 G04
80
PHASE
20
60
10
40
GAIN
0
20
–10
0
– 20
– 20
– 30
1
FREQUENCY (kHz)
200
150
100
50
TA = – 40°C
–1 0
10
FREQUENCY (Hz)
40
20
1
40
1.5
30
1.0
20
0.5
10
30
1495 G11
VS = ± 2.5V
70
60
AV = 1
50
40
30
AV = 5
20
AV = 10
10
0
0
25
100
Capacitive Load Handling
OVERSHOOT (%)
2.0
PHASE MARGIN (DEG)
50
0
10
FREQUENCY (Hz)
1495 G09
80
OUTPUT VOLTAGE (2µV/DIV)
60
20
15
10
SUPPLY VOLTAGE (V)
60
100
VS = ±15V
VCM = 0V
GBW
9 10
VS = ± 2.5V
1495 G08
PHASE MARGIN
2.5
1 2 3 4 5 6 7 8
COMMON MODE VOLTAGE (V)
0
1
70
3.0
TA = 85°C
80
0.1Hz to 10Hz
Output Voltage Noise
3.5
FREQUENCY (kHz)
TA = 25°C
0.5
0
10
Gain Bandwidth and Phase
Margin vs Supply Voltage
8
1.5
Noise Current Spectrum
VS = ± 2.5V
1495 G10
5
TA = – 40°C
100
250
– 40
0
100
1495 G06
CURRENT NOISE (fA/√Hz)
30
NOISE VOLTAGE (nV/√Hz)
100
PHASE SHIFT (DEG)
VOLTAGE GAIN (dB)
40
0.1
TA = 25°C
Noise Voltage Spectrum
300
120
VS = ± 2.5V
TA = 85°C
200
– 0.5
1000
VS = 5V, 0V
1495 G05
Gain and Phase Shift
vs Frequency
50
INPUT BIAS CURRENT (nA)
1000
VS = 5V, 0V
SATURATION VOLTAGE (mV)
SATURATION VOLTAGE (mV)
1000
Input Bias Current
vs Common Mode Voltage
Output Saturation Voltage
vs Load Current (Output High)
10
TIME (1s/DIV)
1495 G07
100
1000
10000
CAPACITIVE LOAD (pF)
100000
1495 G12
LT1494/LT1495/LT1496
U W
TYPICAL PERFORMANCE CHARACTERISTICS
VS = ± 2.5V
90
80
70
60
50
40
30
20
10
0
0.01
0.1
1
FREQUENCY (kHz)
100
POWER SUPPLY REJECTION RATIO (dB)
COMMON MODE REJECTION RATIO (dB)
100
Power Supply Rejection Ratio
vs Frequency
POSITIVE
SUPPLY
80
70
60
50
NEGATIVE
SUPPLY
40
30
20
0.1
1
FREQUENCY (kHz)
20
OFFSET VOLTAGE CHANGE (µV)
OFFSET VOLTAGE CHANGE (µV)
30
VS = ±2.5V
–10
–20
–30
– 40
80
10
5
RL = 1M
0
RL = 100k
–5
–10
VS = ±15V
RL = 1M
CL = 100pF
0
1
2
4
3
OUTPUT VOLTAGE (V)
5
6
40
RL = 100k
20
0
RL = 1M
–20
– 40
– 80
–20 –15 –10 –5
0
5
10
OUTPUT VOLTAGE (V)
1495 G17
Small-Signal Response
VS = 5V, 0V
1495 G19
VS = ± 15V
60
– 60
1495 G16
Small-Signal Response
VS = ±15V
10
1495 G15
VS = 5V, 0V
15
– 20
20 40 60 80 100 120 140 160 180 200
TIME AFTER POWER-UP (SEC)
0.1
1
FREQUENCY (kHz)
Open-Loop Gain
VS = ±15V
–15
0
0.1
0.01
10
OFFSET VOLTAGE CHANGE (µV)
40
10
AV = 1
1
Open-Loop Gain
VS = 5V, 0V
VS = ±15V
AV = 10
10
1495 G14
Warm-Up Drift vs Time
0
100
10
1495 G13
20
1000
VS = ± 2.5V
90
0
0.01
10
Output Impedance vs Frequency
OUTPUT IMPEDANCE (kΩ)
Common Mode Rejection Ratio
vs Frequency
VS = 5V, 0V
RL = 1M
CL = 100pF
15
20
1495 G18
Large-Signal Response
VS = 5V, 0V
1495 G20
VS = 5V, 0V
RL = 1M
CL = 100pF
1495 G21
9
LT1494/LT1495/LT1496
U
W
U
U
APPLICATIONS INFORMATION
Start-Up Characteristics
Reverse Battery
Micropower op amps are sometimes not micropower
during start-up, wreaking havoc on low current supplies.
In the worst case, there may not be enough supply current
available to take the system up to nominal voltages. Figure
1 is a graph of LT1495 supply current vs supply voltage
for the three limit cases of input offset that could occur
during start-up. The circuits are shown in Figure 2. One
circuit creates a positive offset, forcing the output to come
up saturated high. Another circuit creates a negative
offset, forcing the output to come up saturated low, while
the last brings up the output at half supply. In all cases, the
supply current is well behaved. Supply current is highest
with the output forced high, so if one amplifier is unused,
it is best to force the output low or at half supply.
The LT1494/LT1495/LT1496 are protected against reverse
battery voltages up to 18V. In the event a reverse battery
condition occurs, the supply current is typically less than
100nA (inputs grounded and outputs open). For typical
single supply applications with ground referred loads and
feedback networks, no other precautions are required. If
the reverse battery condition results in a negative voltage
at either the input pins or output pin, the current into the
pin should be limited by an external resistor to less than
10mA.
SUPPLY CURRENT PER AMPLIFIER (µA)
5
4
OUTPUT HIGH
3
2
Inputs
While the LT1494/LT1495/LT1496 will function normally
with its inputs taken above the positive supply, the common mode range does not extend beyond approximately
300mV below the negative supply at room temperature.
The device will not be damaged if the inputs are taken lower
than 300mV below the negative supply as long as the current out of the pin is limited to less than 10mA. However,
the output phase is not guaranteed and the supply current
will increase.
OUTPUT LOW
Output
1
OUTPUT VS /2
The graph, Capacitive Load Handling, shows amplifier stability with the output biased at half supply. If the output is
to be operated within about 100mV of the positive rail, the
allowable load capacitance is less. With this output voltage, the worst case occurs at AV = 1 and light loads, where
the load capacitance should be less than 500pF with a 5V
supply and less than 100pF with a 30V supply.
0
0
1
2
3
4
SUPPLY VOLTAGE (V)
5
1495 F01
Figure 1. Start-Up Characteristics
VS
VS
VS
Rail-to-Rail Operation
+
+
–
–
VS /2
+
–
1495 F02
OUTPUT HIGH
OUTPUT LOW
OUTPUT AT VS /2
Figure 2. Circuits for Start-Up Characteristics
10
The simplified schematic, Figure 3, details the circuit
design approach of the LT1494/LT1495/LT1496. The
amplifier topology is a three-stage design consisting of a
rail-to-rail input stage, that continues to operate with the
inputs above the positive rail, a folded cascode second
stage that develops most of the voltage gain, and a rail-torail common emitter stage that provides the current gain.
LT1494/LT1495/LT1496
U
U
W
U
APPLICATIONS INFORMATION
V+
D1
D2
D3
Q10
D7
Q13
Q14
Q15
Q20
+
I1
IN
IN –
Q1 Q2
Q3
Q4
Q7
Q5
0.5
Q6
0.5
0.5
0.5
(V +) – 0.8V
Q16
OUT
Q19
Q17
Q11
Q21
+
C1
+
D4
Q12
D5
D6
Q18
Q22
+
Q9
R1
Q8
R2
I2
1495 F03
Figure 3. Simplified Schematic
The input stage is formed by two diff amps Q1-Q2 and Q3Q6. For signals with a common mode voltage between VEE
and (VCC – 0.8V), Q1 and Q2 are active. When the input
common mode exceeds (VCC – 0.8V), Q7 turns on,
diverting the current from diff amp Q1-Q2 to current
mirror Q8-Q9. The current from Q8 biases on the other diff
amp consisting of PNP’s Q5-Q6 and NPN’s Q3-Q4. Though
Q5-Q6 are driven from the emitters rather than the base,
the basic diff amp action is the same. When the common
mode voltage is between (VCC – 0.8V) and VCC, devices Q3
and Q4 act as followers, forming a buffer between the
amplifier inputs and the emitters of the Q5-Q6. If the
common mode voltage is taken above VCC, Schottky
diodes D1 and D2 reverse bias and devices Q3 and Q4 then
act as diodes. The diff amp formed by Q5-Q6 operates
normally, however, the input bias current increases to the
emitter current of Q5-Q6, which is typically 180nA. The
graph, Input Bias Current vs Common Mode Voltage
found in the Typical Performance Characteristics section,
shows these transitions at three temperatures.
The collector currents of the two-input pairs are combined
in the second stage consisting of Q11 to Q16, which
furnishes most of the voltage gain. Capacitor C1 sets the
amplifier bandwidth. The output stage is configured for
maximum swing by the use of common emitter output
devices Q21 and Q22. Diodes D4 to D6 and current source
Q15 set the output quiescent current.
11
LT1494/LT1495/LT1496
U
TYPICAL APPLICATIONS N
13µA, 0kHz to 10kHz Voltage to Frequency Converter
270k
10M*
3.9M*
5V
–
390Ω
562k*
1µF
–
0.0082µF
+
VIN
0V TO 2.5V
1/2
LT1495
+
100k
3.9M
20M
5V
LTC®1440
+
1.2
REFERENCE
LTC1440
12pF
1N5712
3.6M TYP
SELECT FOR 100Hz
AT VIN = 0.025V
1N4148
360k
39k
15k
10M
100pF†
OUTPUT
0kHz TO 10kHz
Q1
0.05µF
–
Q1: ZTX-849
*1% METAL FILM
†
POLYSTYRENE
1/2
LT1495
0V – 2.5V = 0kHz – 10kHz
SUPPLY CURRENT = 6.2µA QUIESCENT
= 13.3µA AT f = 10kHz
LINEARITY: ± 0.03%
PSRR (4.4V TO 36V): 10ppm/V
TEMPERATURE DRIFT: 250ppm/°C
+
1495 TA07
6µA, AV = 1000, Chopper Stabilized Amplifier
0.2µF
1µF
φ1
5V
+
INPUT
1µF
φ2
1/2
LT1495
1M
–
φ2
1M
–
1/2
LT1495
10M
φ1
– 5V
OUTPUT
+
10k
10M
10k
10M
φ1
–
0.047µF
–
1/2
LTC1441
+
1/2
10M
10M
12
5V
+LTC1441
– 5V
φ2
GAIN: 1000
OFFSET: 1µV
DRIFT: 50nV/°C
SUPPLY CURRENT: 5.5µA
BANDWIDTH: 0.2Hz
CLOCK RATE: 4Hz
CD4016 QUAD
1495 TA08
LT1494/LT1495/LT1496
U
TYPICAL APPLICATIONS N
Filter Frequency Response
6th Order 10Hz Elliptic Lowpass Filter
10k
100k
15nF
215k
215k
30nF
100nF
–10
+
–20
1/2 LT1495
215k
100nF
GAIN (dB)
e in
15nF
0
–
200k
–30
–40
10nF
100k
VS = 5V, 0V
IS = 2µA + ein /150k
ZEROS AT 50Hz AND 60Hz
–50
–60
15nF
15nF
169k
169k
1
10k
80.6k
10
100
FREQUENCY (Hz)
100nF
1000
LT1495/96 • TA04
+
169k
100nF
OUTPUT
1/2 LT1495
–
30nF
200k
10nF
100k
1495 TA03
U
PACKAGE DESCRIPTION
MS8 Package
8-Lead Plastic MSOP
(Reference LTC DWG # 05-08-1660)
0.118 ± 0.004*
(3.00 ± 0.102)
8
7 6
5
0.118 ± 0.004**
(3.00 ± 0.102)
0.193 ± 0.006
(4.90 ± 0.15)
1
2 3
4
0.043
(1.10)
MAX
0.007
(0.18)
0.034
(0.86)
REF
0° – 6° TYP
0.021 ± 0.006
(0.53 ± 0.015)
SEATING
PLANE
0.009 – 0.015
(0.22 – 0.38)
0.0256
(0.65)
BSC
0.005 ± 0.002
(0.13 ± 0.05)
MSOP (MS8) 1100
* DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH,
PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
13
LT1494/LT1495/LT1496
U
PACKAGE DESCRIPTION
N8 Package
8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
0.400*
(10.160)
MAX
8
7
6
5
1
2
3
4
0.255 ± 0.015*
(6.477 ± 0.381)
0.300 – 0.325
(7.620 – 8.255)
0.009 – 0.015
(0.229 – 0.381)
(
0.130 ± 0.005
(3.302 ± 0.127)
0.045 – 0.065
(1.143 – 1.651)
0.065
(1.651)
TYP
+0.035
0.325 –0.015
+0.889
8.255
–0.381
)
0.125
(3.175) 0.020
MIN (0.508)
MIN
0.018 ± 0.003
0.100
(2.54)
BSC
(0.457 ± 0.076)
N8 1098
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
0.189 – 0.197*
(4.801 – 5.004)
8
7
6
5
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
SO8 1298
1
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
0.053 – 0.069
(1.346 – 1.752)
0°– 8° TYP
0.016 – 0.050
(0.406 – 1.270)
0.014 – 0.019
(0.355 – 0.483)
TYP
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
14
2
3
4
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
BSC
LT1494/LT1495/LT1496
U
PACKAGE DESCRIPTION
N Package
14-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
0.770*
(19.558)
MAX
14
13
12
11
10
9
8
1
2
3
4
5
6
7
0.255 ± 0.015*
(6.477 ± 0.381)
0.130 ± 0.005
(3.302 ± 0.127)
0.300 – 0.325
(7.620 – 8.255)
0.045 – 0.065
(1.143 – 1.651)
0.020
(0.508)
MIN
0.065
(1.651)
TYP
0.009 – 0.015
(0.229 – 0.381)
+0.035
0.325 –0.015
0.005
(0.125)
MIN 0.100
(2.54)
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
BSC
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
(
+0.889
8.255
–0.381
)
0.018 ± 0.003
(0.457 ± 0.076)
0.125
(3.175)
MIN
N14 1098
S Package
14-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
0.337 – 0.344*
(8.560 – 8.738)
14
13
12
11
10
9
8
0.228 – 0.244
(5.791 – 6.197)
0.150 – 0.157**
(3.810 – 3.988)
1
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
2
3
4
5
6
0.053 – 0.069
(1.346 – 1.752)
0.004 – 0.010
(0.101 – 0.254)
0° – 8° TYP
0.016 – 0.050
(0.406 – 1.270)
0.014 – 0.019
(0.355 – 0.483)
TYP
7
0.050
(1.270)
BSC
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
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.
S14 1298
15
LT1494/LT1495/LT1496
U
TYPICAL APPLICATIONS N
0nA to 200nA Current Meter
Battery Current Monitor
IL
CHARGE
100pF
RSENSE
0.1Ω
DISCHARGE
–
A2
1/2 LT1495
RA
RA
RA
R4
10k
–
A1
1/2 LT1495
RA
+
DISCHARGE
OUT
1.5V
1/2
LT1495
R3
2k
FULL-SCALE
ADJUST
( )
RB
1/2
LT1495
+
R2
9k
+
R
VO = IL B RSENSE
RA
CHARGE
OUT
RB
–
–
INPUT
CURRENT
+
2N3904
2N3904
R1
10M
12V
5V
FOR RA = 1k, RB = 10k
VO
= 1V/A
IL
1495 TA05
µA
1.5V
IS = 3µA WHEN IIN = 0
NO ON/OFF SWITCH
REQUIRED
0µA TO
200µA
1495 TA06
High Side Current Sense
VS = 2.7V TO 36V
RA
1k
VO = IL
–
RSENSE
1Ω
FOR RA = 1k, RB = 10k, RS = 1Ω
VO
= 10 V/A
IL
LT1494
+
+
LOAD
IL
( RRBA )RS
RB
10k
OUTPUT OFFSET ≈ IS • RB ≈ 10mV
OUTPUT CLIPS AT VS – 2.4V
VO
_
1495 TA09
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC 1440/41/42
Micropower Single/Dual Comparators with 1% Reference
LTC1440: Single, LTC1441/42: Dual
LTC1443/44/45
Micropower Quad Comparators with 1% Reference
LTC1443: 1.182 Reference
LTC1444/45: 1.221V Reference and Adjustable Hysteresis
LT1466/LT1467
75µA Dual/Quad Rail-to-Rail Input and Output Op Amps
390µV VOS(MAX), Gain Bandwidth = 120kHz
LT1490A/LT1491A
50µA Dual/Quad Rail-to-Rail Input and Output Op Amps
950µV VOS(MAX), Gain Bandwidth = 200kHz
LTC1540
Nanopower Single Comparator with 1% Reference
350nA Supply Current
LT1636
Single Over-The-Top Micropower,
Rail-to-Rail Input and Output Op Amp
225µV VOS(MAX), IS = 55µA (MAX), Gain-Bandwidth = 200kHz
Shutdown Pin, MSOP
LT1672/LT1673/LT1674
2µA MAX, A V ≥ 5 Single/Dual/Quad Over-The-Top Precision
Rail-to-Rail Input and Output Op Amps
Decompensated Version of the LT1494/LT1495/LT1496
AV ≥ 5, Gain-Bandwidth = 12kHz
LT2078/LT2079
55µA Dual/Quad Single Supply Op Amps
120µV VOS(MAX), Gain Bandwidth = 200kHz
LT2178/LT2179
17µA Dual/Quad Single Supply Op Amps
120µV VOS(MAX), Gain Bandwidth = 60kHz
LT1782
Micropower, Over-The-Top, SOT-23, Rail-to-Rail
Input and Output Op Amp
SOT-23, 800µV VOS(MAX) , IS = 55µA (Max),
Gain-Bandwidth = 200kHz, Shutdown Pin
LT1783
1.2MHz, Over-The-Top, Micropower, Rail-to-Rail
Input and Output Op Amp in SOT-23
SOT-23, 800µV VOS(MAX) , IS = 300µA (Max),
Gain-Bandwidth = 1.2MHz, Shutdown Pin
®
16
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417● (408) 432-1900
FAX: (408) 434-0507 ● TELEX: 499-3977 ● www.linear.com
149456fb LT/TP 0801 1.5K REV B • PRINTED IN USA
LINEAR TECHNOLOGY CORPORATION 1997
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