LINER LT1783CS6 1.25mhz, over-the-top micropower, rail-to-rail input and output op amp in sot-23 Datasheet

LT1783
1.25MHz, Over-The-Top
Micropower, Rail-to-Rail
Input and Output Op Amp in SOT-23
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DESCRIPTIO
FEATURES
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Operates with Inputs Above V +
Rail-to-Rail Input and Output
Micropower: 300µA Supply Current Max
Small SOT-23 Package
Gain Bandwidth product: 1.25MHz
Slew Rate: 0.42V/µs
Low Input Offset Voltage: 800µV Max
Single Supply Input Range: 0V to 18V
High Output Current: 18mA Min
Specified on 3V, 5V and ±5V Supplies
Output Shutdown on 6-Lead Version
Reverse Battery Protection to 18V
High Voltage Gain: 1500V/mV
Operating Temperature Range: – 40°C to 85°C
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APPLICATIO S
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The input range of the LT1783 includes ground, and a
unique feature of this device is its Over-The-TopTM operation capabilitity with either or both of its inputs above the
positive rail. The inputs handle 18V both differential and
common mode, independent of supply voltage. The input
stage incorporates phase reversal protection to prevent
false outputs from occurring even when the inputs are 9V
below the negative supply.
The LT1783 can drive loads up to 18mA and still maintain
rail-to-rail capability. A shutdown feature on the 6-lead
version can disable the part, making the output high
impedance and reducing quiescent current to 5µA. The
LT1783 op amp is available in the 5- and 6-lead
SOT-23 packages. For applications requiring lower power,
refer to the LT1782.
Portable Instrumentation
Battery- or Solar-Powered Systems
Sensor Conditioning
Supply Current Sensing
Battery Monitoring
MUX Amplifiers
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®1783 is a 1.25MHz op amp available in the small
SOT-23 package that operates on all single and split
supplies with a total voltage of 2.5V to 18V. The amplifier
draws less than 300µA of quiescent current and has
reverse battery protection, drawing negligible current for
reverse supply voltages up to 18V.
TYPICAL APPLICATIO
Distribution of Input Offset Voltage
25
Positive Supply Rail Current Sense
5V TO 18V
200Ω
5V
0.2Ω
200Ω
LOAD
ILOAD
+
LT1783
2N3904
–
VOUT = 2Ω(ILOAD)
0V TO 4.3V
2k
VS = 5V, 0V
VCM = 2.5V
PERCENTAGE OF AMPLIFIERS
V+
20
15
10
5
0
–900
1783 TA01
–600 –300
0
300
600
INPUT OFFSET VOLTAGE (µV)
900
1782 G25
1
LT1783
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ABSOLUTE MAXIMUM RATINGS
(Note 1)
Total Supply Voltage (V + to V –) .............................. 18V
Input Differential Voltage ........................................ 18V
Input Pin Voltage to V – ............................... + 24V/– 10V
Shutdown Pin Voltage Above V – ............................ 18V
Shutdown Pin Current ....................................... ±10mA
Output Short-Circuit Duration (Note 2) ........... Indefinite
Operating Temperature Range (Note 10) – 40°C to 85°C
Specified Temperature Range ...................... 0°C to 70°C
Junction Temperature........................................... 150°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
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PACKAGE/ORDER INFORMATION
TOP VIEW
5 V
OUT 1
V– 2
+
ORDER PART
NUMBER
LT1783CS5
4 –IN
+IN 3
ORDER PART
NUMBER
+
6 V
OUT 1
V– 2
+ –
+IN 3
TOP VIEW
+ –
5 SHDN
LT1783CS6
4 –IN
S5 PACKAGE
5-LEAD PLASTIC SOT-23
S5 PART MARKING
S6 PACKAGE
6-LEAD PLASTIC SOT-23
TJMAX = 150°C, θJA = 250°C/ W
LTLF
TJMAX = 150°C, θJA = 230°C/ W
S6 PART MARKING
LTIU
Consult factory for Industrial and Military grade parts.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the specified temperature range, otherwise specifications are TA = 25°C.
VS = 3V, 0V; VS = 5V, 0V, VCM = VOUT = half supply, for the 6-lead part VPIN5 = 0V, pulse power tested unless otherwise specified.
SYMBOL PARAMETER
CONDITIONS
VOS
TA = 25°C
0°C ≤ TA ≤ 70°C
●
0°C ≤ TA ≤ 70°C
VCM = 18V (Note 3)
Input Offset Voltage
Input Offset Voltage Drift (Note 7)
IOS
IB
Input Offset Current
Input Bias Current
VCM = 18V (Note 3)
SHDN or VS = 0V, VCM = 0V to 18V
Input Bias Current Drift
0°C ≤ TA ≤ 70°C
MIN
TYP
MAX
UNITS
400
800
950
µV
µV
●
2
5
µV/°C
●
●
4
8
7
nA
µA
●
●
45
35
0.1
80
60
nA
µA
nA
●
0.06
nA/°C
Input Noise Voltage
0.1Hz to 10Hz
0.6
µVP-P
en
Input Noise Voltage Density
f = 1kHz
20
nV/√Hz
in
Input Noise Current Density
f = 1kHz
0.14
pA/√Hz
RIN
Input Resistance
Differential
Common Mode, VCM = 0V to (VCC – 1V)
Common Mode, VCM = 0V to 18V
1.3
1
0.5
MΩ
GΩ
MΩ
CIN
0.65
0.3
Input Capacitance
5
Input Voltage Range
●
0
pF
18
V
CMRR
Common Mode Rejection Ratio
(Note 3)
VCM = 0V to VCC – 1V
VCM = 0V to 18V (Note 6)
●
●
90
68
100
80
dB
dB
PSRR
Power Supply Rejection Ratio
VS = 3V to 12.5V, VCM = VO = 1V
●
90
100
dB
AVOL
Large-Signal Voltage Gain
VS = 3V, VO = 500mV to 2.5V, RL = 10k
VS = 3V, 0°C ≤ TA ≤ 70°C
200
133
1500
●
V/mV
V/mV
VS = 5V, VO = 500mV to 4.5V, RL = 10k
VS = 5V, 0°C ≤ TA ≤ 70°C
400
250
1500
●
V/mV
V/mV
2
LT1783
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the specified temperature range, otherwise specifications are TA = 25°C.
VS = 3V, 0V; VS = 5V, 0V, VCM = VOUT = half supply, for the 6-lead part VPIN5 = 0V, pulse power tested unless otherwise specified.
SYMBOL PARAMETER
CONDITIONS
VOL
Output Voltage Swing LOW
No Load
ISINK = 5mA
VS = 5V, ISINK = 10mA
●
●
●
VOH
Output Voltage Swing HIGH
VS = 3V, No Load
VS = 3V, ISOURCE = 5mA
●
●
2.91
2.6
2.94
2.8
V
V
VS = 5V, No Load
VS = 5V, ISOURCE = 10mA
●
●
4.91
4.5
4.94
4.74
V
V
VS = 3V, Short to GND
VS = 3V, Short to VCC
5
15
10
30
mA
mA
VS = 5V, Short to GND
VS = 5V, Short to VCC
15
20
30
40
mA
mA
ISC
Short-Circuit Current (Note 2)
Minimum Supply Voltage
Reverse Supply Voltage
IS
MIN
Supply Current
(Note 4)
●
MAX
UNITS
3
200
330
8
400
600
mV
mV
mV
2.5
●
IS = –100µA
TYP
2.7
18
V
V
210
300
350
µA
µA
●
Supply Current, SHDN
VPIN5 = 2V, No Load (Note 8)
●
5
18
µA
Shutdown Pin Current
VPIN5 = 0.3V, No load (Note 8)
VPIN5 = 2V, No Load (Note 8)
VPIN5 = 5V, No Load (Note 8)
●
●
0.5
2
5
8
nA
µA
µA
Shutdown Output Leakage Current
VPIN5 = 2V, No Load (Note 8)
●
0.05
1
µA
Maximum Shutdown Pin Current
VPIN5 = 18V, No Load (Note 8)
●
10
30
µA
VL
Shutdown Pin Input Low Voltage
(Note 8)
●
0.3
V
VH
Shutdown Pin Input High Voltage
(Note 8)
●
tON
Turn-On Time
VPIN5 = 5V to 0V, RL = 10k (Note 8)
25
µs
tOFF
Turn-Off Time
VPIN5 = 0V to 5V, RL = 10k (Note 8)
3
µs
GBW
Gain Bandwidth Product
(Note 3)
f = 5kHz
0°C ≤ TA ≤ 70°C
750
600
1250
●
kHz
kHz
Slew Rate
(Note 5)
AV = –1, RL = ∞
0°C ≤ TA ≤ 70°C
0.24
0.21
0.42
●
V/µs
V/µs
ISHDN
SR
2
V
FPBW
Full-Power Bandwidth (Note 9)
VOUT = 2VP-P
66
kHz
tS
Settling Time
VS = 5V, ∆VOUT = 2V to 0.1%, AV = –1
12
µs
THD
Distortion
VS = 3V, VO = 2VP-P, AV = 1, RL = 10k, f = 1kHz
0.001
%
VS = ±5V, VCM = 0V,VOUT = 0V, for the 6-lead part VSHDN = V–
VOS
Input Offset Voltage
Input Offset Voltage Drift (Note 7)
IOS
Input Offset Current
IB
Input Bias Current
TA = 25°C
0°C ≤ TA ≤ 70°C
●
0°C ≤ TA ≤ 70°C
Input Bias Current Drift
0°C ≤ TA ≤ 70°C
Input Noise Voltage
0.1Hz to 10Hz
µV
µV
500
900
1050
●
2
5
µV/°C
●
4
8
nA
●
40
80
●
0.06
nA/°C
1
µVP-P
nA
en
Input Noise Voltage Density
f = 1kHz
20
nV/√Hz
in
Input Noise Current Density
f = 1kHz
0.14
pA/√Hz
3
LT1783
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the specified temperature range, otherwise specifications are TA = 25°C.
VS = ±5V, VCM = 0V,VOUT = 0V, for the 6-lead part VSHDN = V–, unless otherwise specified.
SYMBOL PARAMETER
CONDITIONS
RIN
Input Resistance
Differential
Common Mode, VCM = –5V to 13V
CIN
Input Capacitance
Input Voltage Range
●
●
MIN
TYP
0.65
0.3
1.3
0.5
MΩ
MΩ
5
pF
●
–5
MAX
13
UNITS
V
CMRR
Common Mode Rejection Ratio
VCM = –5V to 13V
●
68
80
dB
AVOL
Large-Signal Voltage Gain
VO = ±4V, RL= 10k
0°C ≤ TA ≤ 70°C
160
●
70
50
V/mV
V/mV
VOL
Output Voltage Swing LOW
No Load
ISINK = 5mA
ISINK = 10mA
●
●
●
VOH
Output Voltage Swing HIGH
No Load
ISOURCE = 5mA
ISOURCE = 10mA
●
●
●
4.91
4.6
4.5
4.94
4.8
4.74
ISC
Short-Circuit Current (Note 2)
Short to GND
0°C ≤ TA ≤ 70°C
18
15
30
●
VS = ±1.5V to ±9V
●
90
PSRR
Power Supply Rejection Ratio
IS
Supply Current
–4.997
–4.8
–4.67
–4.992
–4.6
–4.4
V
V
V
V
V
V
mA
mA
100
dB
230
325
375
µA
µA
●
Supply Current, SHDN
VPIN5 = –3V, VS = ±5V, No Load (Note 8)
●
6
20
µA
Shutdown Pin Current
VPIN5 = –4.7V, VS = ±5V, No load (Note 8)
VPIN5 = –3V, VS = ±5V, No Load (Note 8)
●
●
0.5
2
8
nA
µA
Maximum Shutdown Pin Current
VPIN5 = 9V, VS = ±9V (Note 8)
●
10
30
µA
Shutdown Output Leakage Current
VPIN5 = –7V, VS = ±9V, No Load (Note 8)
●
0.05
1
µA
VL
Shutdown Pin Input Low Voltage
VS = ±5V (Note 8)
●
–4.7
V
VH
Shutdown Pin Input High Voltage
VS = ±5V (Note 8)
●
tON
Turn-On Time
VPIN5 = 0V to –5V, RL = 10k (Note 8)
●
25
µs
tOFF
Turn-Off Time
VPIN5 = –5V to 0V, RL = 10k (Note 8)
●
3
µs
GBW
Gain Bandwidth Product
f = 5kHz
0°C ≤ TA ≤ 70°C
800
700
1300
●
kHz
kHz
AV = –1, RL = ∞, VO = ±4V, Measured at VO = ±2V
0°C ≤ TA ≤ 70°C
0.26
0.23
0.45
●
V/µs
V/µs
ISHDN
SR
Slew Rate
–2.8
V
FPBW
Full-Power Bandwidth (Note 9)
VOUT = 8VP-P
18
kHz
tS
Settling Time
∆VOUT = 4V to 0.1%, AV = 1
10
µs
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: A heat sink may be required to keep the junction temperature
below absolute maximum.
Note 3: VS = 5V limits are guaranteed by correlation to VS = 3V and
VS = ±5V or VS = ±9V tests.
Note 4: VS = 3V limits are guaranteed by correlation to VS = 5V and
VS = ±5V or VS = ±9V tests.
Note 5: Guaranteed by correlation to slew rate at VS = ±5V, and GBW at
VS = 3V and VS = ±5V tests.
4
Note 6: This specification implies a typical input offset voltage of 1.8mV at
VCM = 18V and a maximum input offset voltage of 7.2mV at VCM = 18V.
Note 7: This parameter is not 100% tested.
Note 8: Specifications apply to 6-lead SOT-23 with shutdown.
Note 9: Full-power bandwidth is calculated from the slew rate.
FPBW = SR/2πVP.
Note 10: The LT1783 is guaranteed functional over the operating
temperature range – 40°C to 85°C.
LT1783
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TYPICAL PERFOR A CE CHARACTERISTICS
Supply Current vs Supply Voltage
400
280
TA = 125°C
260
240
TA = 25°C
220
200
180
TA = –55°C
160
140
5
VS = 5V, 0V
300
4
200
100
TA = –55°C
VOUT (V)
INPUT OFFSET VOLTAGE CHANGE (µV)
300
0
TA = 125°C
–100
TA = 25°C
–200
2
4
6
8
10 12 14
SUPPLY VOLTAGE (V)
16
18
1
2
3
4
TOTAL SUPPLY VOLTAGE (V)
0
10000
250
200
TA = –55°C
150
100
TA = 25°C
50
TA = 125°C
0
OUTPUT SATURATION VOLTAGE (V)
Output Saturation Voltage vs Load
Current (Output Low)
1
VS = ±2.5V
VOD = 30mV
TA = 125°C
0.1
TA = –55°C
TA = 25°C
VS = ±2.5V
VOD = 30mV
TA = 125°C
0.1
0.01
TA = 25°C
TA = –55°C
0.01
1µ
–50
3.8 4 4.2 4.4 4.6 4.8 5 5.2 5.4 5.6 14 16 18
COMMON MODE VOLTAGE (V)
10µ
100µ
1m
SOURCING LOAD CURRENT (A)
10m
0.001
10µ
100µ
1m
SINKING LOAD CURRENT (A)
1µ
1783 G04
1783 G03
Output Saturation Voltage vs
Input Overdrive
1783 G05
Output Short-Circuit Current vs
Temperature
100
10m
0.1Hz to 10Hz Noise Voltage
55
VS = ±2.5V
VS = ±5V
OUTPUT HIGH
OUTPUT CURRENT (mA)
50
10
OUTPUT LOW
1
10
20
30
40
50
INPUT OVERDRIVE (mV)
SOURCING CURRENT
45
40
SINKING CURRENT
35
VS = ±2.5V
NO LOAD
0
NOISE VOLTAGE (400nV/DIV)
INPUT BIAS CURRENT (nA)
1783 G02a
1
50000
OUTPUT SATURATION VOLTAGE (mV)
0
–10–8 –6 –4 –2 0 2 4 6 8 10 12 14 16 18
VIN (V)
5
Output Saturation Voltage vs Load
Current (Output High)
20000
–
1783 G02
Input Bias Current vs Common
Mode Voltage
30000
+
1
1783 G01
40000
5V
2
–300
–400
120
3
VIN
OUTPUT SATURATION VOLTAGE (V)
SUPPLY CURRENT (µA)
Output Voltage vs Large Input
Voltage
Minimum Supply Voltage
60
1783 G06
30
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
1783 G06a
0
1
2
3
4 5 6
TIME (sec)
7
8
9
10
1783 G07
5
LT1783
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TYPICAL PERFOR A CE CHARACTERISTICS
Noise Voltage Density vs
Frequency
70
60
50
40
30
20
1
100
1k
FREQUENCY (Hz)
10
VS = ±2.5V
2.5
1.5
1.0
0.5
0
10
100
1k
FREQUENCY (Hz)
60
30
40
20
20
GAIN
10
0
0
–20
–10
–40
–20
–60
1k
10k
1783 G08
10k
1783 G10
Slew Rate vs Temperature
1400
0.8
VS = ±5V
f = 5kHz
VS = ±2.5V
0.7
SLEW RATE (V/µs)
1350
1300
1250
1200
1150
RISING
0.6
0.5
FALLING
0.4
0.3
1100
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
0.2
–50
125
–25
0
25
50
75
TEMPERATURE (°C)
100
1783 G11
125
1783 G12
Gain Bandwidth Product and
Phase Margin vs Supply Voltage
Gain Bandwidth and Phase
Margin vs Load Resistance
PHASE MARGIN
PHASE
MARGIN (DEG)
60
65
60
PHASE MARGIN
55
55
GAIN BAINDWIDTH
PRODUCT (kHz)
GAIN BAINDWIDTH
PRODUCT (kHz)
1300
GAIN BANDWIDTH PRODUCT
1250
1200
0
2
4
6
8 10 12 14 16
TOTAL SUPPLY VOLTAGE (V)
18
1783 G13
1400
GAIN BANDWIDTH PRODUCT
1200
VS = 2.5V
AV = –1
RF = RG = 10k
f = 5kHz
1000
800
1k
10k
LOAD RESISTANCE (Ω)
100k
1783 G14
PHASE
MARGIN (DEG)
65
AV = –1
RF = RG = 10k
f = 5kHz
6
–80
10M
100k
1M
FREQUENCY (Hz)
1783 G09
Gain Bandwidth Product vs
Temperature
GAIN BANDWIDTH (kHz)
80
40
–30
1
100
PHASE
50
2.0
10k
120
VS = ±2.5V
60
GAIN (dB)
INPUT NOISE CURRENT DENSITY (pA/√Hz)
3.0
VS = ±2.5V
PHASE SHIFT (DEG)
INPUT NOISE VOLTAGE DENSITY (nV/√Hz)
70
10
Gain and Phase Shift vs
Frequency
Input Noise Current vs Frequency
LT1783
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TYPICAL PERFOR A CE CHARACTERISTICS
PSRR vs Frequency
CMRR vs Frequency
60
POSITIVE SUPPLY
50
40
30
NEGATIVE SUPPLY
20
10
0
10k
100k
FREQUENCY (Hz)
1k
VS = ±2.5V
100
AV = 100
90
80
70
60
50
10
AV = 10
1
0.1
AV = 1
40
30
10k
1M
100
VS = ±2.5V
OUTPUT IMPEDANCE (Ω)
70
–10
Output Impedance vs Frequency
110
VS = ±2.5V
80
COMMON MODE REJECTION RATIO (dB)
POWER SUPPLY REJECTION RATIO (dB)
90
100k
FREQUENCY (Hz)
0.01
100
1M
1k
10k
100k
FREQUENCY (Hz)
1M
1783 G15
1783 G17
1783 G16
Disabled Output Impedance vs
Frequency (Note 8)
Settling Time to 0.1% vs Output
Step
1M
4
40
3
35
AV = –1
1k
OVERSHOOT (%)
10k
1
VS = ±5V
0
–1
100
100
1k
AV = 1
AV = –1
0
2
4
0.010
0.1
THD + NOISE (%)
0.1
THD + NOISE (%)
OUTPUT SWING (VP-P)
1
VS = 3V, 0V
VOUT = 2VP-P
VCM = 1.2V
RL = 10k
VS = ±5V
VS = ±2.5V
AV = –1
0
100
0.01
VS = 3V, 0V
VIN = 0.5V TO 2.5V
VS = 3V, 0V
VIN = 0.2V TO 2.2V
AV = 1
DISTORTION ≤ 1%
AV = 1
0.0001
1k
10k
FREQUENCY (Hz)
100k
1783 G20
VS = ±1.5V
VIN = ±1V
VS = 3V TOTAL
AV = 1
VIN = 2VP-P AT 1kHz
0.001
0.001
2
10000
Total Harmonic Distortion + Noise
vs Load Resistance
1
12
6
100
1000
CAPACITIVE LOAD (pF)
1783 G19
Total Harmonic Distortion + Noise
vs Frequency
8
AV = 10
1783 G18
Undistorted Output Swing vs
Frequency
4
AV = 5
10
6 8 10 12 14 16 18 20
SETTLING TIME (µs)
1783 G17a
10
AV = 1
15
0
–4
1M
20
5
–3
10k
100k
FREQUENCY (Hz)
25
10
–2
VS = ±2.5V
VPIN5 (SHUTDOWN) = 2.5V
VS = 5V, 0V
VCM = 2.5V
30
2
OUTPUT STEP (V)
OUTPUT IMPEDANCE (Ω)
AV = 1
100k
Capacitive Load Handling
Overshoot vs Capacitive Load
10
100
1k
10k
FREQUENCY (Hz)
100k
1783 G21
0.0001
100
1k
10k
LOAD RESISTANCE TO GROUND (Ω)
100k
1783 G22
7
LT1783
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Total Harmonic Distortion + Noise
vs Output Voltage Amplitude
AV = –1
RF = RG = 100k
VS = 3V, 0V
VCM = 1.5V
0.1
AV = 1
VS = 3V, 0V
VCM = 1.5V
0.01
AV = 1
VS = ±1.5V
VCM = 0V
0.001
0
1
2
OUTPUT VOLTAGE AMPLITUDE (VP-P)
RL = 2k
RL = 10k
RL = 50k
–6 –5 –4 –3 –2 –1 0 1 2 3
OUTPUT VOLTAGE (V)
3
275
VS = ±5V
SUPPLY CURRENT PER AMPLIFIER (µA)
AV = –1
RF = RG = 100k
VS = ±1.5V
VCM = 0V
1
THD + NOISE (%)
INPUT OFFSET VOLTAGE CHANGE (50µV/DIV)
10
Supply Current vs SHDN Pin
Voltage
Open-Loop Gain
1783 G23
4
5
6
250
TA = 125°C
225
200
VS = 5V, 0V
TA = 25°C
175
150
TA = –55°C
125
100
75
50
25
0
0
0.5
1
1.5
2
SHUTDOWN PIN VOLTAGE (V)
1783 G24
2.5
1783 G25
Small-Signal Response
Large-Signal Response
VS = ±5V
AV = 1
CL = 15pF
VS = ±5V
AV = 1
CL = 15pF
1783 G26
1783 G27
U
W
U
U
APPLICATIO S I FOR ATIO
Supply Voltage
Inputs
The positive supply pin of the LT1783 should be bypassed
with a small capacitor (typically 0.1µF) 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 LT1783 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.
The LT1783 is protected against reverse battery voltages
up to 18V. In the event a reverse battery condition occurs,
the supply current is less than 1nA.
8
For input voltages about 0.8V or more below V +, the PNP
input stage is active and the input bias current is typically
–40nA. When the input common mode voltage is within
0.5V of the positive rail, the NPN stage is operating and the
LT1783
U
W
U
U
APPLICATIO S I FOR ATIO
input bias current is typically 80nA. Increases in temperature will cause the voltage at which operation switches
from the PNP input stage to the NPN input stage to move
towards V +. The input offset voltage of the NPN stage is
untrimmed and is typically 1.8mV.
A Schottky diode in the collector of the input transistors,
along with special geometries for these NPN transistors,
allow the LT1783 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
30µA at room temperature. The input offset voltage is
typically 1.8mV when operating above V +. The LT1783 will
operate with its inputs 18V above V – regardless of V +.
The inputs are protected against excursions as much as
10V below V – by an internal 1k resistor in series with each
input and a diode from the input to the negative supply.
The input stage of the LT1783 incorporates phase reversal
protection to prevent the output from phase reversing for
inputs up to 9V below V –. There are no clamping diodes
between the inputs and the maximum differential input
voltage is 18V.
Output
The output of the LT1783 can swing to within 60mV of the
positive rail with no load and within 3mV of the negative
rail with no load. When monitoring input voltages within
60mV of the positive rail or within 3mV of the negative rail,
gain should be taken to keep the output from clipping. The
LT1783 can sink and source over 30mA at ±5V supplies,
sourcing current is reduced to 10mA at 3V total supplies
as noted in the Electrical Characteristics.
The LT1783 is internally compensated to drive at least
400pF 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 to distortion in op amps:
output crossover distortion as the output transitions from
sourcing to sinking current, and distortion caused by
nonlinear common mode rejection. If the op amp is
operating inverting, there is no common mode induced
distortion. If the op amp is operating in the PNP input stage
(input is not within 0.8V of V +), the CMRR is very good,
typically 100dB. When the LT1783 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 LT1783 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, “Total Harmonic Distortion + Noise vs Output Voltage Amplitude.”
Gain
The open-loop gain is almost independent of load when
the output is sourcing current. This optimizes performance in single supply applications where the load is
returned to ground. The typical performance curve of
open-loop gain for various loads shows the details.
Shutdown
The 6-lead part includes a shutdown feature that disables
the part, reducing quiescent current and making the
output high impedance. The part can be shut down by
bringing the SHDN pin 1.2V or more above V –. When shut
down, the supply current is about 5µA and the output
leakage current is less than 1µA (V – ≤ VOUT ≤ V +). In
normal operation, the SHDN pin can be tied to V – or left
floating. See the Typical Performance Characteristics
curves, “Supply Current vs Shutdown Voltage.”
9
LT1783
W
W
SI PLIFIED SCHE ATIC
V+
Q2
Q1
Q3
D1
SHDN
R1
6k
R2
1k
Q4
Q19
– IN
Q17
+
J1
Q7
R3
1k
10µA
Q11
Q8
OUT
+IN
Q5
Q18
Q15
Q9
Q24
Q20
Q12
Q16
Q26
Q25 Q23
Q22
D3
Q6
D4
Q10
Q13
Q14
R5
8k
R4
8k
D5
Q21
V–
1783 SS
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
S5 Package
5-Lead Plastic SOT-23
(LTC DWG # 05-08-1633)
2.80 – 3.00
(0.110 – 0.118)
(NOTE 3)
2.60 – 3.00
(0.102 – 0.118)
1.50 – 1.75
(0.059 – 0.069)
0.35 – 0.55
(0.014 – 0.022)
1.90
(0.074)
REF
0.00 – 0.15
(0.00 – 0.006)
0.09 – 0.20
(0.004 – 0.008)
(NOTE 2)
0.90 – 1.45
(0.035 – 0.057)
0.35 – 0.50
0.90 – 1.30
(0.014 – 0.020)
(0.035 – 0.051)
FIVE PLACES (NOTE 2)
S5 SOT-23 0599
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DIMENSIONS ARE INCLUSIVE OF PLATING
3. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
4. MOLD FLASH SHALL NOT EXCEED 0.254mm
5. PACKAGE EIAJ REFERENCE IS SC-74A (EIAJ)
10
0.95
(0.037)
REF
LT1783
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
S6 Package
6-Lead Plastic SOT-23
(LTC DWG # 05-08-1634)
2.80 – 3.00
(0.110 – 0.118)
(NOTE 3)
PIN 1
1.90
(0.074)
REF
2.6 – 3.0
(0.110 – 0.118)
1.50 – 1.75
(0.059 – 0.069)
0.35 – 0.55
(0.014 – 0.022)
0.00 – 0.15
(0.00 – 0.006)
0.09 – 0.20
(0.004 – 0.008)
(NOTE 2)
0.95
(0.037)
REF
0.90 – 1.45
(0.035 – 0.057)
0.35 – 0.50
0.90 – 1.30
(0.014 – 0.020)
(0.035 – 0.051)
SIX PLACES (NOTE 2)
S6 SOT-23 0898
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DIMENSIONS ARE INCLUSIVE OF PLATING
3. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
4. MOLD FLASH SHALL NOT EXCEED 0.254mm
5. PACKAGE EIAJ REFERENCE IS SC-74A (EIAJ)
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.
11
LT1783
U
TYPICAL APPLICATIO S
Current Source
VCC
LT1634-1.25
R1
+
LT1783
2N3906
–
IOUT =
1.25V
R1
1783 TA02
Protected Fault Conditions
OK!
–18V
OK!
5V
V+
V+
LT1783
LT1783
+
24V
REVERSE BATTERY
18V
5V
+
OK!
LT1783
LT1783
10V
INPUT DIFFERENTIAL VOLTAGE
5V
+
OK!
INPUT OVERVOLTAGE
INPUTS BELOW GROUND
1783 TA03
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1782
Micropower, Over-The-Top SOT-23 Rail-to-Rail Input
and Output Op Amp
SOT-23 Package, Micropower 40µA per Amplifier, Rail-to-Rail Input
and Output , 200kHz GBW
LT1490/LT1491
Dual/Quad Over-The-Top Micropower Rail-to-Rail Input
and Output Op Amps
Single Supply Input Range: –0.4V to 44V, Micropower 50µA per
Amplifier, Rail-to-Rail Input and Output , 200kHz 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, 0.4V/µs, Over-The-Top Micropower
Rail-to-Rail Input and Output Op Amps
170µA Supply Current, Single Supply Input Range: –0.4V to 44V,
Rail-to-Rail Input and Output
12
Linear Technology Corporation
1783f LT/TP 0400 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 1999
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