LT1490A/LT1491A
Dual/Quad Over-The-Top
Micropower Rail-to-Rail
Input and Output Op Amps
FEATURES DESCRIPTION
n
Low Input Offset Voltage: 500V Max
The LT 1490A/LT1491A are dual and quad op amps with a
n
Output Swings to 10mV Max from V
low input offset voltage of 500V max. The LT1490A/LT1491A
n
Rail-to-Rail Input and Output
operate on all single and split supplies with a total voltage of
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Micropower: 50A/Amplifier Max 2V to 44V, drawing only 40A of quiescent current per ampli-
n
Over-The-Top Input Common Mode Range Extends fier. These amplifiers are reverse supply protected; they draw
+
44V Above V , Independent of V virtually no current for reverse supply up to 18V. The input
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range of the LT1490A/LT1491A includes both supplies and
Specified on 3V, 5V and 15V Supplies
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the output swings to both supplies. Unlike most micropower
High Output Current: 20mA
n
op amps, the LT1490A/LT1491A can drive heavy loads; their
Output Drives 10,000pF with Output Compensation
n rail-to-rail outputs drive 20mA. The LT1490A/LT1491A are
Reverse Battery Protection to 18V
n unity-gain stable and drive all capacitive loads up to 10,000pF
No Supply Sequencing Problems
n when optional 0.22F and 150 compensation is used.
High Voltage Gain: 1500V/mV
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High CMRR: 98dB
The LT1490A/LT1491A have a unique input stage that oper-
n
No Phase Reversal
ates and remains high impedance when above the positive
n
Gain Bandwidth Product: 200kHz
supply. The inputs take 44V both differential and common
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Tiny 3mm 3mm 0.8mm DFN Package
mode even when operating on a 3V supply. Built-in resistors
protect the inputs for faults below the negative supply up to
APPLICATIONS
15V. There is no phase reversal of the output for inputs 15V
+
below V or 44V above V , independent of V .
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Battery- or Solar-Powered Systems
Portable Instrumentation
The LT1490A dual op amp is available in the 8-pin MSOP, PDIP
Sensor Conditioning
and SO packages. For space limited applications LT1490A is
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Supply Current Sensing
available in a 3mm 3mm 0.8mm, dual fine pitch leadless
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Battery Monitoring
package (DFN). The quad LT1491A is available in the 14-pin
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Micropower Active Filters
SO, PDIP and 5mm 3mm 0.8mm DFN packages.
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4mA to 20mA Transmitters
L, LT, LTC, LTM, Over-The-Top, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners. Protected by U.S. Patents including 5825228.
TYPICAL APPLICATION Battery Monitor
R R
S
A
0.2
2k Q1
CHARGER
+ 2N3904
VOLTAGE
R
I
BATT A 1/4 LT1491A
2k
1/4 LT1491A LOGIC
+
R
B
Q2
2k
LOGIC HIGH (5V) = CHARGING
+ 2N3904
LOGIC LOW (0V) = DISCHARGING
R
B
1/4 LT1491A
2k
LOAD
+
+
R
G 1/4 LT1491A V
OUT
10k
V = 12V
BATT
S1
10k 90.9k
1490A TA01
V V
OUT OUT S1 = OPEN, GAIN = 1 R = R
A B
I = = AMPS
BATT
(R )(R /R )(GAIN) GAIN S1 = CLOSED, GAIN = 10 V = 5V, 0V
S G A S
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1LT1490A/LT1491A
ABSOLUTE MAXIMUM RATINGS (Note 1)
Total Supply Voltage (V+ to V) ............................... 44V Specified Temperature Range (Note 4)
Differential Input Voltage ......................................... 44V LT1490AC/LT1490AI ............................40C to 85C
Input Current (Note 9) ......................................... 12mA LT1491AC/LT1491AI .............................40C to 85C
Output Short-Circuit Duration (Note 2) ........ Continuous LT1490AH/LT1491AH ......................... 40C to 125C
Operating Temperature Range (Note 3) Junction Temperature .......................................... 150C
LT1490AC/LT1491AC ...........................40C to 85C Junction Temperature (DD/DHC Package) ........... 125C
LT1490AI/LT1491AI .............................40C to 85C Storage Temperature Range ................. 65C to 150C
LT1490AH/LT1491AH ......................... 40C to 125C Storage Temperature Range
DD/DHC Package .............................. 65C to 125C
Lead Temperature (Soldering, 10 sec) .................. 300C
PIN CONFIGURATION
LT1490A LT1490A LT1490A
TOP VIEW
TOP VIEW
+
TOP VIEW 1 8 +
OUT A V
OUT A 1 8 V
+
OUT A 1 8 V
IN A 2 7 OUT B
IN A 2 7 OUT B
IN A 2 7 OUT B A A
A
+IN A 3 6 IN B
+IN A 3 6 IN B
+IN A 3 6 IN B
B
B
B
V 4 5 +IN B
V 4 5 +IN B
V 4 5 +IN B
MS8 PACKAGE
8-LEAD PLASTIC MSOP
N8 PACKAGE S8 PACKAGE
DD PACKAGE
8-LEAD PDIP 8-LEAD PLASTIC SO
T = 150C, = 250C/W
JMAX JA
8-LEAD (3mm w 3mm) PLASTIC DFN
T = 150C, = 130C/W (N8)
JMAX JA
T = 125C, = 160C/W (NOTE 2)
JMAX JA
T = 150C, = 190C/W (S8)
JMAX JA
UNDERSIDE METAL CONNECTED TO V
LT1491A LT1491A
TOP VIEW
TOP VIEW
OUT A 1 16 OUT D
OUT A 1 14 OUT D
IN A 2 15 IN D
IN A 2 13 IN D A D
A D +IN A 3 14 +IN D
+IN A 3 12 +IN D
V+ 4 13 V
+
V 4 11 V
+IN B 5 12 +IN C
C
+IN B 5 10 +IN C B
B C IN B 6 11 IN C
IN B 6 9 IN C
OUT B 7 10 OUT C
OUT B 7 8 OUT C
NC 8 9 NC
N PACKAGE S PACKAGE
14-LEAD PDIP 14-LEAD PLASTIC SO DHC16 PACKAGE
16-LEAD (5mm w 3mm) PLASTIC DFN
T = 150C, = 110C/W (N)
JMAX JA
T = 150C, = 150C/W (S) T = 125C, = 160C/W (NOTE 2)
JMAX JA JMAX JA
UNDERSIDE METAL CONNECTED TO V
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