LINER LT1496CS

LT1495/LT1496
1.5µA Max, Dual and Quad
Precision Rail-to-Rail
Input and Output Op Amps
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DESCRIPTION
FEATURES
■
■
■
■
■
■
■
■
■
■
Low Supply Current: 1.5µA Max
Rail-to-Rail Input and Output
Low Offset Voltage: 375µV Max
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®1495/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
LT1495/LT1496 easy to use in harsh environments.
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APPLICATIONS
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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 LT1495 is available in plastic 8-pin PDIP and SO-8
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.
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TYPICAL APPLICATION
TC VOS Distribution
Micropower Integrating Current Sense
RI
1M
30
0.1µF
25
RS
0.1Ω 1M
1/2 LT1495
–
+
1/2 LT1495
IL
LOAD
100 AMPLIFIERS
VS = ±2.5V
–40°C TO 85°C
20
–
UNITS
VCC
RESET
VO
+
10M
10
5
10M
1495 TA01
VCC
200k
OUTPUT SWITCHES
WHEN ILdt = 0.98 VCC
15
( )
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
LT1495/LT1496
W W
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ABSOLUTE MAXIMUM RATINGS
Total Supply Voltage (V + to V –) .............................. 36V
Input Differential Voltage ......................................... 36V
Input Current ...................................................... ±10mA
Output Short-Circuit Duration .......................Continuous
Operating Temperature Range ................ – 40°C to 85°C
Specified Temperature Range (Note 1) ... – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Junction Temperature ........................................... 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
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PACKAGE/ORDER INFORMATION
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
LT1495CN8
LT1495CS8
S8 PART MARKING
1495
TJMAX = 150°C, θJA = 130°C/ W (N8)
TJMAX = 150°C, θJA = 190°C/ W (S8)
ORDER PART
NUMBER
TOP VIEW
14 OUT D
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
A
D
LT1496CN
LT1496CS
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 = 110°C/ W (N8)
TJMAX = 150°C, θJA = 150°C/ W (S8)
Consult factory for Industrial and Military grade parts.
ELECTRICAL CHARACTERISTICS
TA = 25°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half supply, unless otherwise noted.
SYMBOL PARAMETER
VOS
Input Offset Voltage
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
2
Power Supply Rejection Ratio
Minimum Operating Supply Voltage
Output Voltage Swing LOW
CONDITIONS
VS = 5V
VS = 3V
(Note 3)
VCM = 10V (Note 4)
(Note 3)
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
MIN
100
50
0
90
74
90
TYP
150
200
250
180
20
4
185
10
500
250
MAX
375
475
1000
360
100
36
106
95
99
2.1
50
210
2.2
100
410
UNITS
µV
µV
pA
nA
pA
µVP-P
nV/√Hz
fA/√Hz
V/mV
V/mV
V
dB
dB
dB
V
mV
mV
LT1495/LT1496
ELECTRICAL CHARACTERISTICS
TA = 25°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half supply, unless otherwise noted.
SYMBOL
VOH
PARAMETER
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
Reverse Supply Voltage
Slew Rate
Gain Bandwidth Product
SR
GBW
CONDITIONS
No Load
ISOURCE = 100µA
(Note 3)
(Note 4)
IS = 10µA per Amplifier
AV = –1, VS = ±5V
f = 100Hz
MIN
TYP
V+ – 0.07
V+ – 0.035
V+ – 0.32
0.7
V+ – 0.160
1.3
1.0
–18
0.4
MAX
1.5
1.0
2.7
UNITS
V
V
mA
µA
V
V/ms
kHz
0°C ≤ TA ≤ 70°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half supply, unless otherwise noted.
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
(Note 2)
(Note 3)
VCM = 10V (Note 4)
(Note 3)
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
89
64
89
●
No Load
ISINK = 100µA
No Load
ISOURCE = 100µA
(Note 3)
(Note 4)
●
●
●
●
●
V+ – 0.08
V+ – 0.36
0.6
●
TYP
175
225
0.4
250
240
20
280
150
MAX
425
525
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/°C
pA
nA
pA
V/mV
V/mV
V
dB
dB
dB
V
mV
mV
V
V
mA
µA
– 40°C ≤ TA ≤ 85°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half supply, unless otherwise noted. (Note 1)
SYMBOL PARAMETER
VOS
Input Offset Voltage
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
Power Supply Rejection Ratio
Minimum Operating Supply Voltage
CONDITIONS
VS = 5V
VS = 3V
(Note 2)
(Note 3)
VCM = 10V (Note 4)
(Note 3)
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
88
88
TYP
200
250
0.4
250
275
20
215
115
MAX
475
575
2
1700
170
36
106
75
99
2.6
2.7
UNITS
µV
µV
µV/°C
pA
nA
pA
V/mV
V/mV
V
dB
dB
dB
V
3
LT1495/LT1496
ELECTRICAL CHARACTERISTICS
– 40°C ≤ TA ≤ 85°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VO = half supply, unless otherwise noted. (Note 1)
SYMBOL PARAMETER
Output Voltage Swing LOW
VOL
VOH
Output Voltage Swing HIGH
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
CONDITIONS
No Load
ISINK = 100µA
No Load
ISOURCE = 100µA
(Note 3)
(Note 4)
MIN
●
●
●
●
●
V+ – 0.10
V+ – 0.38
0.4
●
TYP
60
245
V+ – 0.05
V+ – 0.19
0.9
1.5
MAX
120
490
TYP
200
25
20
360
MAX
575
1000
100
2.3
UNITS
mV
mV
mV
mV
mA
µA
TA = 25°C, VS = ±15V, VCM = VO = 0V, unless otherwise noted.
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
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
CONDITIONS
MIN
VO = ±10V, RL = 100k
100
– 15
100
96
VCM = – 15V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
14.78
14.62
0.7
21
120
120
–14.85
–14.75
14.89
14.81
1.5
1.4
–14.70
–14.50
2.0
UNITS
µV
pA
pA
V/mV
V
dB
dB
V
V
V
V
mA
µA
0°C ≤ TA ≤ 70°C, VS = ±15V, VCM = VO = 0V, unless otherwise noted.
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
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
4
CONDITIONS
MIN
●
●
●
VO = ±10V, RL = 100k
●
●
VCM = –14.8V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
●
●
60
– 15
98
94
●
●
●
●
●
●
14.76
14.58
0.6
TYP
225
250
20
240
MAX
625
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
pA
pA
V/mV
V
dB
dB
V
V
V
mV
mA
µA
LT1495/LT1496
ELECTRICAL CHARACTERISTICS
–40°C ≤ TA ≤ 85°C, VS = ±15V, VCM = VO = 0V, unless otherwise noted. (Note 1)
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
ISC
IS
Short-Circuit Current
Supply Current per Amplifier
CONDITIONS
MIN
TYP
250
250
20
200
●
●
●
VO = ±10V, RL = 100k
50
– 15
96
92
●
●
VCM = –14.8V to 14V
VS = ±5V to ±15V
RL = 1M
RL = 100k
RL = 1M
RL = 100k
●
●
21
114
120
–14.83
–14.72
14.87
14.77
1.1
2.0
●
●
14.74
14.54
0.4
●
●
●
MAX
675
1700
170
●
–14.66
–14.44
3.0
UNITS
µV
pA
pA
V/mV
V
dB
dB
V
V
V
V
mA
µA
Note 2: This parameter is not 100% tested.
Note 3: VS = 5V limit guaranteed by correlation to VS = 3V and VS = ±15V
tests.
Note 4: VS = 3V limit guaranteed by correlation to VS = 5V and VS = ±15V
tests.
The ● denotes specifications which apply over the full operating
temperature range.
Note 1: The LT1495/LT1496 are designed, characterized and expected to
meet these extended temperature limits, but are not tested at – 40°C and
85°C. Guaranteed I grade parts are available; consult factory.
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TYPICAL PERFORMANCE CHARACTERISTICS
Distribution of Input Offset Voltage
PERCENT OF UNITS (%)
16
VS = 5V, 0V
LT1495/LT1496
4500 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
0
60
20
TEMPERATURE (°C)
80
100
1495 G02
1
3
2
4
TOTAL SUPPLY VOLTAGE (V)
5
1495 G03
5
LT1495/LT1496
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TYPICAL PERFORMANCE CHARACTERISTICS
1000
VS = 5V, 0V
SATURATION VOLTAGE (mV)
SATURATION VOLTAGE (mV)
1000
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
6
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
vs Common Mode Voltage
Output Saturation Voltage
vs Load Current (Output High)
INPUT BIAS CURRENT (nA)
Output Saturation Voltage
vs Load Current (Output Low)
10
TIME (1s/DIV)
1495 G07
100
1000
10000
CAPACITIVE LOAD (pF)
100000
1495 G12
LT1495/LT1496
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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
7
LT1495/LT1496
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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 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
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.
1
OUTPUT VS /2
0
1
2
3
4
SUPPLY VOLTAGE (V)
5
1495 F01
Figure 1. Start-Up Characteristics
VS
VS
+
+
–
–
VS
VS /2
Rail-to-Rail Operation
+
–
1495 F02
OUTPUT HIGH
OUTPUT LOW
OUTPUT AT VS /2
Figure 2. Circuits for Start-Up Characteristics
8
While the 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
OUTPUT LOW
0
Inputs
The simplified schematic, Figure 3, details the circuit
design approach of the 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-to-rail common emitter stage that provides the current gain.
LT1495/LT1496
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APPLICATIONS INFORMATION
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 V EE
and (VCC – 0.8V), Q1 and Q2 are active. When the input
common mode exceeds (V CC – 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.
9
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
0V – 2.5V = 0kHz – 10kHz
SUPPLY CURRENT = 6.2µA QUIESCENT
= 13.3 µA AT f = 10kHz
LINEARITY: ± 0.03%
PSRR (4.4V TO 36V): 10ppm/V
TEMPERATURE DRIFT: 250ppm/°C
0.05µF
–
Q1: ZTX-849
*1% METAL FILM
†
POLYSTYRENE
1/2
LT1495
+
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
10
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
LT1495/LT1496
U
PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
N8 Package
8-Lead PDIP (Narrow 0.300)
(LTC DWG # 05-08-1510)
0.300 – 0.325
(7.620 – 8.255)
0.045 – 0.065
(1.143 – 1.651)
(
0.125
(3.175)
MIN
)
0.015
(0.380)
MIN
0.018 ± 0.003
0.100 ± 0.010
(0.457 ± 0.076)
(2.540 ± 0.254)
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
8.255
8
7
6
5
1
2
3
4
0.255 ± 0.015*
(6.477 ± 0.381)
0.005
(0.127)
MIN
+0.025
0.325 –0.015
+0.635
–0.381
0.130 ± 0.005
(3.302 ± 0.127)
0.065
(1.651)
TYP
0.009 – 0.015
(0.229 – 0.381)
0.400*
(10.160)
MAX
N8 0695
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
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)
0.189 – 0.197*
(4.801 – 5.004)
7
8
0.004 – 0.010
(0.101 – 0.254)
5
6
0°– 8° TYP
0.016 – 0.050
0.406 – 1.270
0.050
(1.270)
BSC
0.014 – 0.019
(0.355 – 0.483)
*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
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
SO8 0695
1
3
2
4
N Package
14-Lead PDIP (Narrow 0.300)
(LTC DWG # 05-08-1510)
0.300 – 0.325
(7.620 – 8.255)
0.130 ± 0.005
(3.302 ± 0.127)
0.015
(0.380)
MIN
0.065
(1.651)
TYP
0.009 – 0.015
(0.229 – 0.381)
+0.025
0.325 –0.015
(
+0.635
8.255
–0.381
)
0.125
(3.175)
MIN
0.770*
(19.558)
MAX
0.045 – 0.065
(1.143 – 1.651)
0.005
(0.125)
MIN
14
13
12
11
10
9
8
1
2
3
4
5
6
7
0.255 ± 0.015*
(6.477 ± 0.381)
0.018 ± 0.003
(0.457 ± 0.076)
N14 0695
0.100 ± 0.010
(2.540 ± 0.254)
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
S Package
14-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.337 – 0.344*
(8.560 – 8.738)
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
0.004 – 0.010
(0.101 – 0.254)
0.053 – 0.069
(1.346 – 1.752)
14
13
12
11
10
9
8
0° – 8° TYP
0.016 – 0.050
0.406 – 1.270
0.014 – 0.019
(0.355 – 0.483)
0.050
(1.270)
TYP
0.228 – 0.244
(5.791 – 6.197)
*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
0.150 – 0.157**
(3.810 – 3.988)
1
2
3
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.
4
5
6
7
S14 0695
11
LT1495/LT1496
U
TYPICAL APPLICATIONS N
0nA to 200nA Current Meter
Battery Current Monitor
IL
CHARGE
100pF
RSENSE
0.1Ω
DISCHARGE
RA
RA
–
A2
1/2 LT1495
RA
R4
10k
–
A1
1/2 LT1495
RA
+
DISCHARGE
OUT
–
–
RB
()
RB
FOR RA = 1k, RB = 10k
VO
= 1V/A
IL
1495 TA05
µA
215k
215k
30nF
100nF
0µA TO
200µA
–20
1/2 LT1495
100nF
IS = 3µA WHEN IIN = 0
NO ON/OFF SWITCH
REQUIRED
–10
+
215k
R3
2k
FULL-SCALE
ADJUST
Filter Frequency Response
GAIN (dB)
e in
15nF
1.5V
0
10k
100k
R2
9k
1495 TA06
6th Order 10Hz Elliptic Lowpass Filter
15nF
+
+
R
VO = IL B RSENSE
RA
CHARGE
OUT
1/2
LT1495
1.5V
1/2
LT1495
INPUT
CURRENT
+
2N3904
2N3904
R1
10M
12V
5V
–
200k
–30
–40
10nF
100k
VS = 5V, 0V
IS = 2µA + ein /150k
ZEROS AT 50Hz AND 60Hz
–50
–60
10k
80.6k
15nF
15nF
169k
169k
1
10
100
FREQUENCY (Hz)
100nF
1000
LT1495/96 • TA04
+
169k
100nF
OUTPUT
1/2 LT1495
–
30nF
200k
100k
10nF
1495 TA03
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC1440/41/42
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
LT1490/LT1491
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
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
12
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417● (408) 432-1900
FAX: (408) 434-0507● TELEX: 499-3977 ● www.linear-tech.com
14956f LT/TP 0697 5K • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 1997