LINER LT1490AIN8

LT1490A
Dual Over-The-Top
Micropower Rail-to-Rail
Input and Output Op Amp
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FEATURES
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DESCRIPTIO
Low Input Offset Voltage: 500µV Max
Output Swings to 10mV Max from V –
Rail-to-Rail Input and Output
µA/Amplifier Max
Micropower: 50µ
MSOP Package
Over-The-TopTM Input Common Mode Range Extends
44V Above V –, Independent of V +
Specified on 3V, 5V and ±15V Supplies
High Output Current: 20mA
Output Drives 10,000pF with Output Compensation
Reverse Battery Protection to 18V
No Supply Sequencing Problems
High Voltage Gain: 1500V/mV
High CMRR: 98dB
No Phase Reversal
Gain Bandwidth Product: 200kHz
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APPLICATIO S
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Battery- or Solar-Powered Systems
Portable Instrumentation
Sensor Conditioning
Supply Current Sensing
Battery Monitoring
Micropower Active Filters
4mA to 20mA Transmitters
, LTC and LT are registered trademarks of Linear Technology Corporation.
Over-The-Top is a trademark of Linear Technology Corporation.
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The LT ®1490A is an enhanced version of the popular LT1490
op amp with improved input offset voltage (500µV max) and
output voltage swing (10mV max from V –). It is recommended for all new designs. The LT1490A operates on all
single and split supplies with a total voltage of 2V to 44V,
drawing only 40µA of quiescent current per amplifier. It is
reverse supply protected; it draws virtually no current for
reverse supply up to 18V. The input range of the LT1490A
includes both supplies and the output swings to both supplies. Unlike most micropower op amps, the LT1490A can
drive heavy loads; its rail-to-rail output drives 20mA. The
LT1490A is unity-gain stable and drives all capacitive loads
up to 10,000pF when optional 0.22µF and 150Ω compensation is used.
The LT1490A has a unique input stage that operates and
remains high impedance when above the positive supply.
The inputs take 44V both differential and common mode
even when operating on a 3V supply. Built-in resistors
protect the inputs for faults below the negative supply up to
15V. There is no phase reversal of the output for inputs 15V
below V – or 44V above V –, independent of V +.
The LT1490A dual op amp is available in the 8-pin MSOP,
PDIP and SO packages.
TYPICAL APPLICATIO
Battery Monitor
CHARGER
VOLTAGE
RS
0.2Ω
RA
2k
IBATT
RA´
2k
+
Q1
2N3904
1/2 LT1490A
–
–
1/2 LT1490A
LOGIC
+
RB
2k
RB´
2k
LOAD
+
Q2
2N3904
LOGIC HIGH (5V) = CHARGING
LOGIC LOW (0V) = DISCHARGING
1/2 LT1490A
–
+
+
RG
10k
VBATT = 12V
S1
1/2 LT1490A
VOUT
–
10k
90.9k
S1 = OPEN, GAIN = 1
S1 = CLOSED, GAIN = 10
RA = RB
VS = 5V, 0V
14901A TA01
VOUT
V
IBATT =
= OUT AMPS
(RS)(RG /RA)(GAIN) GAIN
1
LT1490A
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ABSOLUTE MAXIMUM RATINGS (Note 1)
Total Supply Voltage (V + to V –) ............................. 44V
Differential Input Voltage ........................................ 44V
Input Current ..................................................... ±12mA
Output Short-Circuit Duration (Note 2) ........ Continuous
Junction Temperature .......................................... 150°C
Operating Temperature Range
(Note 3) ............................................. – 40°C to 85°C
Specified Temperature Range (Note 4) .. – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
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PACKAGE/ORDER INFORMATION
ORDER PART
NUMBER
TOP VIEW
OUT A
–IN A
+IN A
V–
1
2
3
4
8 V+
7 OUT B
6 –IN B
5 +IN B
LT1490ACMS8
LT1490AIMS8
MS8 PACKAGE
8-LEAD PLASTIC MSOP
MS8 PART MARKING
TJMAX = 150°C, θJA = 250°C/ W
LTNG
LTPU
ORDER PART
NUMBER
TOP VIEW
OUT A
1
–IN A
2
8
V+
7
OUT B
LT1490ACN8
LT1490ACS8
LT1490AIN8
LT1490AIS8
A
+IN A
3
6
–IN B
V–
4
5
+IN B
N8 PACKAGE
8-LEAD PDIP
S8 PACKAGE
8-LEAD PLASTIC SO
B
S8 PART MARKING
TJMAX = 150°C, θJA = 130°C/ W (N8)
TJMAX = 150°C, θJA = 190°C/ W (S8)
1490A
1490AI
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. VS = 3V, 0V; VS = 5V, 0V unless otherwise noted. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage (Note 5)
N8, S8 Package
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
MS8 Package
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
– 40°C ≤ TA ≤ 85°C
VCM = 44V (Note 6)
Input Offset Voltage Drift (Note 9)
IOS
IB
Input Offset Current
Input Bias Current
VCM = 44V (Note 6)
VS = 0V
MIN
TYP
MAX
UNITS
110
500
700
800
µV
µV
µV
220
1000
1200
1400
µV
µV
µV
●
2
4
●
●
0.2
0.8
0.8
nA
µA
●
●
1
3
0.3
8
10
nA
µA
nA
µV/°C
Input Noise Voltage
0.1Hz to 10Hz
1
µVP-P
en
Input Noise Voltage Density
f = 1kHz
50
nV/√Hz
in
Input Noise Current Density
f = 1kHz
0.03
pA/√Hz
RIN
Input Resistance
Differential
Common Mode, VCM = 0V to 44V
2
6
4
17
11
MΩ
MΩ
LT1490A
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. VS = 3V, 0V; VS = 5V, 0V unless otherwise noted. (Note 4)
SYMBOL
PARAMETER
CIN
Input Capacitance
CONDITIONS
MIN
TYP
MAX
4.6
Input Voltage Range
●
0
UNITS
pF
44
V
CMRR
Common Mode Rejection Ratio
(Note 6)
VCM = 0V to VCC – 1V
VCM = 0V to 44V
●
●
84
80
98
98
AVOL
Large-Signal Voltage Gain
VS = 3V, VO = 500mV to 2.5V, RL = 10k
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
200
133
100
1500
●
●
V/mV
V/mV
V/mV
VS = 5V, VO = 500mV to 4.5V, RL = 10k
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
400
250
200
1500
●
●
V/mV
V/mV
V/mV
VS = 3V, No Load
VS = 3V, ISINK = 5mA
●
●
3
250
10
450
mV
mV
VS = 5V, No Load
VS = 5V, ISINK = 5mA
VS = 5V, ISINK = 10mA
●
●
3
250
330
10
500
500
mV
mV
mV
VS = 3V, No Load
VS = 3V, ISOURCE = 5mA
●
●
2.95
2.55
2.978
2.6
V
V
VS = 5V, No Load
VS = 5V, ISOURCE = 10mA
●
●
4.95
4.30
4.978
4.6
V
V
VOL
VOH
ISC
PSRR
Output Voltage Swing Low
Output Voltage Swing High
Short-Circuit Current (Note 2)
Power Supply Rejection Ratio
VS = 3V, Short to GND
VS = 3V, Short to VCC
10
10
15
30
mA
mA
VS = 5V, Short to GND
VS = 5V, Short to VCC
15
15
25
30
mA
mA
84
98
VS = 2.5V to 12.5V, VCM = VO = 1V
Minimum Operating Supply Voltage
Reverse Supply Voltage
IS
GBW
SR
dB
dB
●
2
●
IS = – 100µA per Amplifier
Supply Current per Amplifier
(Note 7)
●
18
dB
2.5
27
40
●
V
V
50
55
µA
µA
Gain Bandwidth Product
(Note 6)
f = 1kHz
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
110
100
90
180
●
●
kHz
kHz
kHz
Slew Rate
(Note 8)
AV = – 1, RL = ∞
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
0.035
0.031
0.030
0.06
●
●
V/µs
V/µs
V/µs
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.
VS = ±15V unless otherwise noted. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage (Note 5)
N8, S8 Package
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
MIN
●
●
MS8 Package
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
TYP
MAX
UNITS
150
700
950
1100
µV
µV
µV
250
1200
1350
1500
µV
µV
µV
3
LT1490A
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. VS = ±15V unless otherwise noted. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
Input Offset Voltage Drift (Note 9)
– 40°C ≤ TA ≤ 85°C
MIN
TYP
MAX
UNITS
µV/°C
●
2
6
IOS
Input Offset Current
●
0.2
0.8
nA
IB
Input Bias Current
●
1
8
nA
Input Noise Voltage
0.1Hz to 10Hz
1
µVP-P
en
Input Noise Voltage Density
f = 1kHz
50
nV/√Hz
in
Input Noise Current Density
f = 1kHz
0.03
pA/√Hz
RIN
Input Resistance
Differential
Common Mode, VCM = – 15V to 14V
CIN
Input Capacitance
Input Voltage Range
6
17
15000
MΩ
MΩ
4.6
pF
●
– 15
CMRR
Common Mode Rejection Ratio
VCM = – 15V to 29V
●
80
98
dB
AVOL
Large-Signal Voltage Gain
VO = ±14V, RL = 10k
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
100
75
50
250
●
●
V/mV
V/mV
V/mV
±14.9
±14.5
±14.5
±14.978
±14.750
±14.670
±25
VO
Output Voltage Swing
No Load
IOUT = ±5mA
IOUT = ±10mA
ISC
Short-Circuit Current (Note 2)
Short to GND
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
±20
±15
±10
VS = ±1.25V to ±22V
●
88
PSRR
Power Supply Rejection Ratio
IS
Supply Current per Amplifier
●
●
29
●
GBW
SR
Gain Bandwidth Product
Slew Rate
f = 1kHz
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
AV = – 1, RL = ∞, VO = ±10V,
Measure at VO = ±5V
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2: A heat sink may be required to keep the junction temperature
below absolute maximum. This depends on the power supply voltage and
how many amplifiers are shorted.
Note 3: The LT1490AC and LT1490AI are guaranteed functional over the
operating temperature range of – 40°C to 85°C.
Note 4: The LT1490AC is guaranteed to meet specified performance from
0°C to 70°C. The LT1490AC is designed, characterized and expected to
meet specified performance from – 40°C to 85°C but is not tested or QA
sampled at these temperatures. The LT1490I is guaranteed to meet
specified performance from –40°C to 85°C.
4
●
●
●
●
V
V
V
mA
mA
mA
98
50
V
dB
70
85
µA
µA
125
110
100
200
kHz
kHz
kHz
0.0375
0.07
V/µs
0.0330
0.0300
V/µs
V/µs
Note 5: ESD (Electrostatic Discharge) sensitive device. Extensive use of
ESD protection devices are used internal to the LT1490A. However, high
electrostatic discharge can damage or degrade the device. Use proper
ESD handling precautions.
Note 6: VS = 5V limits are guaranteed by correlation to VS = 3V and
VS = ±15V tests.
Note 7: VS = 3V limits are guaranteed by correlation to VS = 5V and
VS = ±15V tests.
Note 8: Guaranteed by correlation to slew rate at VS = ±15V and GBW
at VS = 3V and VS = ±15V tests.
Note 9: This parameter is not 100% tested.
LT1490A
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TYPICAL PERFOR A CE CHARACTERISTICS
Supply Current vs Supply Voltage
TA = 125°C
60
TA = 25°C
50
40
TA = –55°C
30
20
10
0
5
0
10 15 20 25 30 35 40
TOTAL SUPPLY VOLTAGE (V)
400
5000
300
3000
200
100
TA = –55°C
TA = 25°C
0
–100
–200
–300
– 400
45
VS = 5V, 0V
INPUT BIAS CURRENT (nA)
CHANGE IN INPUT OFFSET VOLTAGE (µV)
SUPPLY CURRENT PER AMPLIFIER (µA)
80
70
Input Bias Current
vs Common Mode Voltage
Minimum Supply Voltage
1
3
4
2
TOTAL SUPPLY VOLTAGE (V)
1
TA = 25°C
TA = –55°C
10µ
1m
10m
100µ
SOURCING LOAD CURRENT (A)
TA = 25°C
TA = –55°C
10m
1
2
1µ
10µ 100µ 1m
10m
SINKING LOAD CURRENT (A)
7
8
60
50
40
30
9
10
1490A G07
OUTPUT HIGH
20
10
OUTPUT LOW
0
10
30
40
20
INPUT OVERDRIVE (mV)
50
1490A G06
1490A G05
Input Noise Current vs Frequency
0.35
INPUT NOISE CURRENT DENSITY (pA/√Hz)
INPUT NOISE VOLTAGE DENSITY (nV/√Hz)
4 5 6
TIME (SEC)
70
100m
80
3
80
Noise Voltage Density
vs Frequency
NOISE VOLTAGE (400nV/DIV)
0
VS = 5V, 0V
90 NO LOAD
0
1490A G04
0.1Hz to 10Hz Noise Voltage
44
100
TA = 125°C
1m
0.1µ
100m
VS = ±2.5V
5.6
4.4
4.8
5.2
COMMON MODE VOLTAGE (V)
Output Saturation Voltage
vs Input Overdrive
VS = 5V, 0V
100m
100m
TA = 125°C
10
1490A G03
OUTPUT SATURATION VOLTAGE (mV)
OUTPUT SATURATION VOLTAGE (V)
OUTPUT SATURATION VOLTAGE (V)
VS = 5V, 0V
1µ
20
Output Saturation Voltage
vs Load Current (Output Low)
TA = 125°C
TA = 25°C
1490A G02
Output Saturation Voltage
vs Load Current (Output High)
10m
30
–10
4.0
5
1490A G01
1
TA = –55°C
0
TA = 125°C
0
1000
70
60
50
40
0.30
0.25
0.20
0.15
0.10
0.05
0
30
1
10
100
FREQUENCY (Hz)
1k
1490A G08
1
10
100
FREQUENCY (Hz)
1k
1490A G09
5
LT1490A
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TYPICAL PERFOR A CE CHARACTERISTICS
Gain and Phase Shift
vs Frequency
Gain Bandwidth Product
vs Temperature
40
30
20
20
0
GAIN
10
–20
0
– 40
–10
– 60
–20
– 80
10
100
FREQUENCY (kHz)
200
VS = ±15V
180
VS = ±1.5V
160
50
25
0
75
TEMPERATURE (°C)
40
200
30
180
170
20
RL = 10k
f = 1kHz
160
COMMON MODE REJECTION RATIO (dB)
220
PHASE MARGIN (DEG)
GAIN BANDWIDTH PRODUCT (kHz)
50
GAIN BANDWIDTH
0
5
10 15 20 25 30 35 40
TOTAL SUPPLY VOLTAGE (V)
100
VS = ±15V
80
VS = ±1.5V
60
40
10
FREQUENCY (kHz)
PHASE MARGIN
250
40
30
20
NEGATIVE SUPPLY
10
0
–10
10
FREQUENCY (kHz)
1
100
1490A G15
Output Impedance vs Frequency
10k
VS = ±15V
VS = ± 2.5V
120
70
60
200
POSITIVE SUPPLY
50
100
50
GAIN BANDWIDTH
150
40
100
30
110
OUTPUT IMPEDANCE (Ω)
300
130
CHANNEL SEPARATION (dB)
VS = ± 2.5V
AV = –1
RF = RG = 100k
f = 1kHz
60
Channel Separation vs Frequency
80
PHASE MARGIN (DEG)
GAIN BANDWIDTH PRODUCT (kHz)
350
VS = ±2.5V
70
1490A G14
1490A G13
Gain Bandwidth Product and
Phase Margin vs Load Resistance
125
–20
1
45
100
PSRR vs Frequency
80
20
10
150
50
25
0
75
TEMPERATURE (°C)
1490A G12
120
240
190
0.04
–50 –25
125
100
CMRR vs Frequency
210
FALLING, VS = ±1.5V
1490A G11
60
230
FALLING, VS = ±15V
120
Gain Bandwidth Product and
Phase Margin vs Supply Voltage
PHASE MARGIN
RISING, VS = ±1.5V
0.08
0.06
140
1490A G10
250
RISING, VS = ±15V
0.10
220
100
–50 –25
–100
1000
–30
1
f = 1kHz
PHASE SHIFT (DEG)
GAIN (dB)
240
60
PHASE
40
80
POWER SUPPLY REJECTION RATIO (dB)
50
100
Slew Rate vs Temperature
0.12
SLEW RATE (V/µs)
VS = ±2.5V
GAIN BANDWIDTH PRODUCT (kHz)
70
60
260
100
90
80
70
60
1k
AV = 100
100
AV = 10
10
1
AV = 1
50
50
1
10
LOAD RESISTANCE (kΩ)
20
100
1490A G16
6
40
0.1
1
10
FREQUENCY (kHz)
100
1490A G17
0.1
0.1
1
10
FREQUENCY (kHz)
100
1490A G18
LT1490A
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TYPICAL PERFOR A CE CHARACTERISTICS
Undistorted Output Swing
vs Frequency
35
10
0
–2
–4
40
AV = 1
AV = 2
AV = 10
AV = 5
30
20
40
60 80 100 120 140 160
SETTLING TIME (µs)
10
100
1000
CAPACITIVE LOAD (pF)
10000
1490A G19
1490A F20
1490A G21
Total Harmonic Distortion + Noise
vs Frequency
Total Harmonic Distortion + Noise
vs Load Resistance
Total Harmonic Distortion + Noise
vs Output Voltage
0.01
1
RL = 10k
VCM = HALF SUPPLY
f = 1kHz
1
VS = ±1.5V
VIN = ±1V
0.1
VS = 3V, 0V
VIN = 0.5V TO 2.5V
AV = –1
VS = ±1.5V
0.1
AV = 1
VS = 3V, 0V
VS = 3V, 0V
VIN = 0.2V TO 2.2V
AV = 1
1
0.1
FREQUENCY (kHz)
10
0.001
0.1
AV = –1
VS = 3V, 0V
0.001
10
1
LOAD RESISTANCE TO GROUND (kΩ)
1490A G22
Open-Loop Gain
AV = 1
VS = ±1.5V
0.01
0.01
AV = –1
0.001
0.01
10
VS = 3V TOTAL
AV = 1
VIN = 2VP-P AT 1kHz
THD + NOISE (%)
10
VS = 3V, 0V
VOUT = 2VP-P
VCM = 1.2V
RL = 50k
0.1
CHANGE IN INPUT OFFSET VOLTAGE
(100µV/DIV)
50
0
0
100
60
10
AV = 1
–10
1
10
FREQUENCY (kHz)
70
20
AV = –1
–8
THD + NOISE (%)
1
2
–6
VS = 5V, 0V
0
0.1
10
80
AV = 1
4
VS = 5V, 0V
ISOURCE = 170µA
90
OVERSHOOT (%)
OUTPUT STEP (V)
OUTPUT SWING (VP-P)
15
100
AV = –1
6
20
Capacitive Load Handling,
Overshoot vs Capacitive Load
VS = ±15V
8
25
5
THD + NOISE (%)
10
DISTORTION ≤1%
VS = ±15V
30
Settling Time to 0.1%
vs Output Step
100
0
1
2
OUTPUT VOLTAGE (VP-P)
1490A G24
1490A G23
Large-Signal Response
3
Small-Signal Response
VS = ±15V
RL = 2k
RL = 10k
RL = 50k
–10V
0V
10V
OUTPUT VOLTAGE (5V/DIV)
1490A G25
VS = ±15V
AV = –1
1490A G26
VS = ±15V
AV = 1
1490A G27
7
LT1490A
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APPLICATIO S I FOR ATIO
Supply Voltage
The positive supply pin of the LT1490A should be bypassed with a small capacitor (about 0.01µF) within an
inch of the pin. When driving heavy loads an additional
4.7µF electrolytic capacitor should be used. When using
split supplies, the same is true for the negative supply pin.
The LT1490A is protected against reverse battery voltages
up to 18V. In the event a reverse battery condition occurs,
the supply current is less than 1nA.
The LT1490A can be shut down by removing V +. In this
condition the input bias current is typically less than 0.5nA,
even if the inputs are 44V above the negative supply.
When operating the LT1490A on total supplies of 20V or
more, the supply must not rise to its final voltage in less
than 1µs. This is especially true if low ESR bypass capacitors are used. A series RLC circuit is formed from the
supply lead inductance and the bypass capacitor. A resistance of 7.5Ω in the supply or in the bypass capacitor will
dampen the tuned circuit enough to limit the rise time.
Inputs
The LT1490A has two input stages, NPN and PNP (see the
Simplified Schematic), resulting in three distinct operating regions as shown in the Input Bias Current vs Common
Mode typical performance curve.
For input voltages about 0.8V or more below V +, the PNP
input stage is active and the input bias current is typically
– 1nA. When the input voltage is about 0.5V or less from
V +, the NPN input stage is operating and the input bias
current is typically 25nA. Increases in temperature will
cause the voltage at which operation switches from the
PNP stage to the NPN stage to move towards V +. The input
offset voltage of the NPN stage is untrimmed and is
typically 600µV.
A Schottky diode in the collector of each NPN transistor of
the NPN input stage allows the LT1490A to operate with
either or both of its inputs above V +. At about 0.3V above
V + the NPN input transistor is fully saturated and the input
bias current is typically 3µA at room temperature. The
input offset voltage is typically 700µV when operating
above V +. The LT1490A will operate with its inputs 44V
above V – regardless of V +.
8
The inputs are protected against excursions as much as
15V below V – by an internal 1k resistor in series with
each input and a diode from the input to the negative
supply. There is no output phase reversal for inputs up to
15V below V –. There are no clamping diodes between the
inputs and the maximum differential input voltage is 44V.
Output
The output voltage swing of the LT1490A is affected by
input overdrive as shown in the typical performance
curves.
The output of the LT1490A can be pulled up to 18V beyond
V + with less than 1nA of leakage current, provided that V +
is less than 0.5V.
The normally reverse-biased substrate diode from the
output to V – will cause unlimited currents to flow when the
output is forced below V –. If the current is transient and
limited to 100mA, no damage will occur.
The LT1490A is internally compensated to drive at least
200pF of capacitance under any output loading conditions. A 0.22µF capacitor in series with a 150Ω resistor
between the output and ground will compensate these
amplifiers for larger capacitive loads, up to 10,000pF, at all
output currents.
Distortion
There are two main contributors of distortion in op amps:
output crossover distortion as the output transitions
from sourcing to sinking current and distortion caused
by nonlinear common mode rejection. Of course, if the op
amp is operating inverting there is no common mode
induced distortion. When the LT1490A switches between input stages there is significant nonlinearity in the
CMRR. Lower load resistance increases the output crossover distortion, but has no effect on the input stage
transition distortion. For lowest distortion the LT1490A
should be operated single supply, with the output always
sourcing current and with the input voltage swing between ground and (V + – 0.8V). See the Typical Performance Characteristics curves.
LT1490A
U
W
U U
APPLICATIO S I FOR ATIO
Gain
in single supply applications where the load is returned to
ground. The typical performance photo of Open-Loop
Gain for various loads shows the details.
The open-loop gain is almost independent of load when
the output is sourcing current. This optimizes performance
U
TYPICAL APPLICATIO S
Square Wave Oscillator
Optional Output Compensation for
Capacitive Loads Greater Than 200pF
59k
5V
100k
+
1/2 LT1490A
100k
+
VIN
1/2 LT1490A
VOUT
CL ≤ 10,000pF
–
–
R
50k
C
0.1µF
1490A TA02
0.22µF
150Ω
f= 1
2RC
VOUT = 5VP-P WITH 5V SUPPLY
IS = 200µA
1490A TA04
AT VS = 5V, R = 50k, C = 1nF
OUTPUT IS 5kHz SLEW LIMITED TRIANGLE WAVE
W
W
SI PLIFIED SCHE ATIC
V+
Q2
Q1
D1
R1
30k
Q3
Q22
D3
D2
R2
1k
Q4
Q19
– IN
Q17
Q7
R3
1k
+
Q8
Q11
OUT
Q16
+IN
2µA
Q18
Q15
Q9
Q5
Q20
Q12
Q6
D4
D5
Q10
Q13
Q14
R4
40k
Q21
R5
40k
V–
ONE AMPLIFIER
1490A SS
9
LT1490A
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
MS8 Package
8-Lead Plastic MSOP
(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
0.040 ± 0.006
(1.02 ± 0.15)
0.007
(0.18)
0.034 ± 0.004
(0.86 ± 0.102)
0° – 6° TYP
SEATING
PLANE 0.012
(0.30)
0.0256
REF
(0.65)
BSC
0.021 ± 0.006
(0.53 ± 0.015)
0.006 ± 0.004
(0.15 ± 0.102)
MSOP (MS8) 1098
* 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
N8 Package
8-Lead PDIP (Narrow 0.300)
(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)
(
+0.035
0.325 –0.015
8.255
+0.889
–0.381
)
0.045 – 0.065
(1.143 – 1.651)
0.065
(1.651)
TYP
0.100
(2.54)
BSC
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
10
0.130 ± 0.005
(3.302 ± 0.127)
0.125
(3.175) 0.020
MIN (0.508)
MIN
0.018 ± 0.003
(0.457 ± 0.076)
N8 1098
LT1490A
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(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)
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
2
3
4
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
BSC
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.
SO8 1298
11
LT1490A
U
TYPICAL APPLICATIO
Ring-Tone Generator
60V
R16
100k
R2
47k
R3
10k
C2
0.47µF
3
+
R1
1/2 LT1490A
33k 2
1
D1
1N4148
R5
100k
5
–
7
R9
300k
R11
10k
10
Z1
15V
100k
+
1/2 LT1490A
R7
16k
–
C4
0.068µF
9
8
13
–
R4
1.6M
R8
620k
CADENCE OSCILLATOR
R10
620k
R12
SMOOTHING FILTER 10k
R14
10k
R13
130k
R15
47k
20Hz OSCILLATOR
C5
0.01µF
+
R17
620Ω
4
–
1/2 LT1490A
12
C1
1µF
Q3
2N3904
C3
0.047µF
+
1/2 LT1490A
6
Q1
IRF628
R6
10k
R24
11 420
14
C7
47µF
R18
100Ω
OPTO1*
R25
4.7k
Q5
2N3904
Z2
15V
R19
620Ω
UP TO
LOAD TEN
PHONES
Q4
2N3906
Q2
IRF9620
*LED OF OPTO1 ILLUMINATES WHEN THE PHONE IS OFF THE HOOK
R26
2k
R23
4.7k
R21
150Ω
C6
0.033µF
POWER AMPLIFIER
–180V
R20
100k
1490A TA03
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1078/LT1079
LT2078/LT2079
Dual/Quad 55µA Max, Single Supply, Precision Op Amps
Input/Output Common Mode Includes Ground, 70µV VOS(MAX)
and 2.5µV/°C Drift (Max), 200kHz GBW, 0.07V/µs Slew Rate
LT1178/LT1179
LT2178/LT2179
Dual/Quad 17µA Max, Single Supply, Precison Op Amps
Input/Output Common Mode Includes Ground, 70µV VOS(MAX)
and 4µV/°C Drift (Max), 85kHz GBW, 0.04V/µs Slew Rate
LT1366/LT1367
Dual/Quad Precision, Rail-to-Rail Input and Output Op Amps
475µV VOS(MAX), 500V/mV AVOL(MIN), 400kHz GBW
LT1636
Single Over-The-Top Micropower Rail-to-Rail Input and Output
Op Amp
55µA Supply Current, VCM Extends 44V above VEE,
Independent of VCC, MSOP Package, Shutdown Function
LT1638/LT1639
Dual/Quad 1.2MHz Over-The-Top Micropower, Rail-to-Rail
Input and Output Op Amps
0.4V/µs Slew Rate, 230µA Supply Current per Amplifier
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
SOT-23, 800µV VOS(MAX), IS =300µA (Max),
Gain-Bandwidth = 1.2MHz, Shutdown Pin
12
Linear Technology Corporation
1490af LT/TP 0300 4K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 2000