NSC LMC7111BIM5

LMC7111
Tiny CMOS Operational Amplifier with Rail-to-Rail Input
and Output
General Description
The LMC7111 is a micropower CMOS operational amplifier
available in the space saving SOT 23-5 package. This
makes the LMC7111 ideal for space and weight critical designs. The wide common-mode input range makes it easy to
design battery monitoring circuits which sense signals above
the V+ supply. The main benefits of the Tiny package are
most apparent in small portable electronic devices, such as
mobile phones, pagers, and portable computers. The tiny
amplifiers can be placed on a board where they are needed,
simplifying board layout.
Features
n Tiny SOT23-5 package saves space
n Very wide common mode input range
n
n
n
n
n
n
Specified at 2.7V, 5V, and 10V
Typical supply current 25 µA at 5V
50 kHz gain-bandwidth at 5V
Similar to popular LMC6462
Output to within 20 mV of supply rail at 100k load
Good capacitive load drive
Applications
n
n
n
n
n
n
Mobile communications
Portable computing
Current sensing for battery chargers
Voltage reference buffering
Sensor interface
Stable bias for GaAs RF amps
Connection Diagrams
8-Pin DIP
5-Pin SOT23-5
DS012352-1
DS012352-2
Top View
Top View
Actual Size
DS012352-19
Ordering Information
Package
Ordering
NSC Drawing
Package
Information
Number
Marking
Transport Media
8-Pin DIP
LMC7111AIN
N08E
LMC7111AIN
Rails
8-Pin DIP
LMC7111BIN
N08E
LMC7111BIN
Rails
LMC7111BIM5
MA05A
A01B
1k units Tape and Reel
LMC7111BIM5X MA05A
A01B
3k Units Tape and Reel
5-Pin SOT23-5
© 1999 National Semiconductor Corporation
DS012352
www.national.com
LMC7111 Tiny CMOS Operational Amplifier with Rail-to-Rail Input and Output
August 1999
Absolute Maximum Ratings (Note 1)
Lead Temp. (Soldering, 10 sec.)
Storage Temperature Range
Junction Temperature (Note 4)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
ESD Tolerance SOT23-5 (Note 2)
ESD Tolerance DIP Package
(Note 2)
Differential Input Voltage
Voltage at Input/Output Pin
Supply Voltage (V+ − V−)
Current at Input Pin
Current at Output Pin (Note 3)
Current at Power Supply Pin
260˚C
−65˚C to +150˚C
150˚C
Operating Ratings (Note 1)
2000V
Supply Voltage
Junction Temperature Range
LMC7111AI, LMC7111BI
Thermal Resistance (θJA)
N Package, 8-Pin Molded DIP
M05A Package,
5-Pin Surface Mount
1500V
± Supply Voltage
(V+) + 0.3V, (V−) − 0.3V
11V
± 5 mA
± 30 mA
30 mA
2.5V ≤ V+ ≤ 11V
−40˚C ≤ TJ ≤ +85˚C
115˚C/W
325˚C/W
2.7V DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 2.7V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
VOS
TCVOS
Parameter
Input Offset Voltage
Conditions
V+ = 2.7V
Typ
LMC7111AI
(Note 5)
Limit
Limit
(Note 6)
(Note 6)
0.9
Input Offset Voltage
LMC7111BI
Units
3
7
mV
5
9
max
2.0
µV/˚C
Average Drift
IB
IOS
Input Bias Current
Input Offset Current
RIN
Input Resistance
+PSRR
Positive Power Supply
Rejection Ratio
−PSRR
Negative Power Supply
Rejection Ratio
VCM
(Note 9)
0.1
(Note 9)
0.01
1
pA
20
max
0.5
0.5
pA
10
10
max
55
55
dB
50
50
min
55
55
dB
50
50
min
Tera Ω
> 10
2.7V ≤ V+ ≤5.0V,
V− = 0V, VO = 2.5V
60
−2.7V ≤ V− ≤−5.0V,
V− = 0V, VO = 2.5V
60
Input Common-Mode
V+ = 2.7V
Voltage Range
For CMRR ≥ 50 dB
−0.10
2.8
CIN
1
20
Common-Mode Input
0.0
0.0
V
0.40
0.40
min
2.7
2.7
V
2.25
2.25
max
3
pF
Capacitance
VO
Output Swing
V+ = 2.7V
RL = 100 kΩ
2.69
0.01
V+ = 2.7V
RL = 10 kΩ
2.65
0.03
ISC
Output Short Circuit
Sourcing, VO = 0V
7
Current
Sinking, VO = 2.7V
www.national.com
7
2
2.68
2.68
V
2.4
2.4
min
0.02
0.02
V
0.08
0.08
max
2.6
2.6
V
2.4
2.4
min
0.1
0.1
V
0.3
0.3
max
1
1
mA
0.7
0.7
min
1
1
mA
0.7
0.7
min
2.7V DC Electrical Characteristics
(Continued)
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 2.7V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
AVOL
Parameter
Voltage Gain
Conditions
Typ
LMC7111AI
(Note 5)
Limit
LMC7111BI
Limit
(Note 6)
(Note 6)
Units
Sourcing
400
V/mv
Sinking
150
V/mv
V+ = +2.7V,
VO = V+/2
20
min
min
IS
Supply Current
45
50
µA
60
65
max
2.7V AC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 2.7V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
Parameter
SR
Slew Rate
GBW
Gain-Bandwidth Product
Conditions
(Note 8)
Typ
LMC7111AI
(Note 5)
Limit
LMC7111BI
Limit
(Note 6)
(Note 6)
Units
0.015
V/µs
40
kHz
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 2: Human body model, 1.5 kΩ in series with 100 pF.
Note 3: Applies to both single-supply and split-supply operation. Continuous short circuit operation at elevated ambient temperature can result in exceeding the
maximum allowed junction temperature at 150˚C.
Note 4: The maximum power dissipation is a function of TJ(max), θJA and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(max)
− TA)/θJA. All numbers apply for packages soldered directly into a PC board.
Note 5: Typical Values represent the most likely parametric norm.
Note 6: All limits are guaranteed by testing or statistical analysis.
Note 7: V+ = 2.7V, VCM = 1.35V and RL connected to 1.35V. For Sourcing tests, 1.35V ≤ VO ≤ 2.7V. For Sinking tests, 0.5V ≤ VO ≤ 1.35V.
Note 8: Connected as Voltage Follower with 1.0V step input. Number specified is the slower of the positive and negative slew rates. Input referred, V+ = 2.7V and
RL = 100 kΩ connected to 1.35V. Amp excited with 1 kHz to produce VO = 1 VPP.
Note 9: Bias Current guaranteed by design and processing.
3V DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 3V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
VCM
Parameter
Conditions
Input Common-Mode
V+ = 3V
Voltage Range
For CMRR ≥ 50 dB
Typ
LMC7111AI
(Note 5)
Limit
Limit
(Note 6)
(Note 6)
0.0
0.0
−0.25
LMC7111BI
Units
V
min
3.2
3
3.0
3.0
V
2.8
2.8
max
www.national.com
3.3V DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 3.3V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
VCM
Parameter
Conditions
Input Common-Mode
V+ = 3.3V
Voltage Range
For CMRR ≥ 50 dB
Typ
LMC7111AI
(Note 5)
Limit
Limit
(Note 6)
(Note 6)
−0.1
−0.1
V
0.00
0.00
min
3.4
3.4
V
3.2
3.2
max
−0.25
3.5
LMC7111BI
Units
5V DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 5V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
VOS
Parameter
Input Offset Voltage
Conditions
V+ = 5V
Typ
LMC7111AI
(Note 5)
Limit
LMC7111BI
Limit
(Note 6)
(Note 6)
0.9
Units
mV
max
TCVOS
Input Offset Voltage
2.0
µV/˚C
Average Drift
IB
IOS
Input Bias Current
Input Offset Current
RIN
Input Resistance
CMRR
Common Mode
(Note 9)
0.1
(Note 9)
0.01
1
1
pA
20
20
max
0.5
0.5
pA
10
10
max
70
60
Tera Ω
> 10
0V ≤ VCM ≤ 5V
85
Rejection Ratio
+PSRR
Positive Power Supply
Rejection Ratio
−PSRR
Negative Power Supply
Rejection Ratio
VCM
5V ≤ V+ ≤10V,
V− = 0V, VO = 2.5V
85
−5V ≤ V− ≤−10V,
V− = 0V, VO = −2.5V
85
Input Common-Mode
V+ = 5V
Voltage Range
For CMRR ≥ 50 dB
70
60
dB
min
−0.3
Common-Mode Input
70
60
dB
min
5.25
CIN
dB
min
−0.20
−0.20
V
0.00
0.00
min
5.20
5.20
V
5.00
5.00
max
3
pF
Capacitance
VO
ISC
Output Swing
Output Short Circuit
V+ = 5V
RL = 100 kΩ
V+ = 5V
4.99
4.98
4.98
Vmin
0.01
0.02
0.02
Vmax
4.98
4.9
4.9
Vmin
RL = 10 kΩ
0.02
0.1
0.1
Vmin
7
5
5
mA
3.5
3.5
min
Sourcing, VO = 0V
Current
Sinking, VO = 3V
AVOL
Voltage Gain
7
5
5
mA
3.5
3.5
min
Sourcing
500
V/mv
Sinking
200
V/mv
V+ = +5V,
VO = V+/2
25
min
min
IS
www.national.com
Supply Current
µA
max
4
5V AC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 5V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
SR
Parameter
Slew Rate
Conditions
Typ
LMC7111AI
(Note 5)
Limit
Limit
(Note 6)
(Note 6)
0.015
0.010
Positive Going Slew Rate
0.027
LMC7111BI
Units
V/µs
(Note 8)
GBW
Gain-Bandwidth Product
50
kHz
Note 10: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 11: Human body model, 1.5 kΩ in series with 100 pF.
Note 12: Applies to both single-supply and split-supply operation. Continuous short circuit operation at elevated ambient temperature can result in exceeding the
maximum allowed junction temperature at 150˚C.
Note 13: The maximum power dissipation is a function of TJ(max), θJA and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(max)
− TA)/θJA. All numbers apply for packages soldered directly into a PC board.
Note 14: Typical Values represent the most likely parametric norm.
Note 15: All limits are guaranteed by testing or statistical analysis.
Note 16: V+ = 5V, VCM = 2.5V and RL connected to 2.5V. For Sourcing tests, 2.5V ≤ VO ≤ 5.0V. For Sinking tests, 0.5V ≤ VO ≤ 2.5V.
Note 17: Connected as Voltage Follower with 1.0V step input. Number specified is the slower of the positive slew rate. The negative slew rate is faster. Input referred,
V+ = 5V and RL = 100 kΩ connected to 1.5V. Amp excited with 1 kHz to produce VO = 1 VPP.
Note 18: Bias Current guaranteed by design and processing.
10V DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 10V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
VOS
TCVOS
Parameter
Input Offset Voltage
Conditions
V+ = 10V
Typ
LMC7111AI
(Note 5)
Limit
Limit
(Note 6)
(Note 6)
3
7
mV
5
9
max
0.9
Input Offset Voltage
LMC7111BI
2.0
Units
µV/˚C
Average Drift
IB
IOS
Input Bias Current
Input Offset Current
RIN
Input Resistance
+PSRR
Positive Power Supply
VCM
0.01
80
−5V ≤ V− ≤−10V,
V− = 0V, VO = 2.5V
80
Rejection Ratio
Input Common-Mode
V+ = 10V
Voltage Range
For CMRR ≥ 50 dB
Negative Power Supply
1
pA
20
max
0.5
0.5
pA
10
10
max
Tera Ω
dB
min
dB
min
−0.2
10.2
CIN
1
20
> 10
5V ≤ V+ ≤10V,
V− = 0V, VO = 2.5V
Rejection Ratio
−PSRR
0.1
Common-Mode Input
−0.15
−0.15
V
0.00
0.00
min
10.15
10.15
V
10.00
10.00
max
3
pF
Capacitance
ISC
Output Short Circuit
Sourcing, VO = 0V
30
Current (Note 9)
Sinking, VO = 10V
30
5
20
20
mA
7
7
min
20
20
mA
7
7
min
www.national.com
10V DC Electrical Characteristics
(Continued)
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 10V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
AVOL
Parameter
Voltage Gain
Conditions
Typ
LMC7111AI
(Note 5)
Limit
LMC7111BI
Limit
(Note 6)
(Note 6)
Units
Sourcing
500
V/mv
Sinking
200
V/mv
V+ = +10V,
VO = V+/2
25
100 kΩ Load
min
min
IS
VO
Supply Current
Output Swing
V+ = 10V
RL = 100 kΩ
V+ = 10V
RL = 10 kΩ
50
60
µA
65
75
max
9.99
9.98
9.98
Vmin
0.01
0.02
0.02
Vmax
9.98
9.9
9.9
Vmin
0.02
0.1
0.1
Vmin
10V AC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = 10V, V− = 0V, VCM = VO = V+/2 and RL > 1 MΩ. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
LMC7111AI
Limit
LMC7111BI
Limit
(Note 6)
(Note 6)
Units
SR
Slew Rate
0.03
V/µs
GBW
Gain-Bandwidth Product
50
kHz
φm
Phase Margin
50
deg
Gm
Gain Margin
15
dB
Input-Referred
(Note 8)
Typ
(Note 5)
f = 1 kHz
Voltage Noise
VCM = 1V
Input-Referred
f = 1 kHz
110
0.03
Current Noise
Note 19: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 20: Human body model, 1.5 kΩ in series with 100 pF.
Note 21: Applies to both single-supply and split-supply operation. Continuous short circuit operation at elevated ambient temperature can result in exceeding the
maximum allowed junction temperature at 150˚C.
Note 22: The maximum power dissipation is a function of TJ(max), θJA and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(max)
− TA)/θJA. All numbers apply for packages soldered directly into a PC board.
Note 23: Typical Values represent the most likely parametric norm.
Note 24: All limits are guaranteed by testing or statistical analysis.
Note 25: V+ = 10V, VCM = 5V and RL connected to 5V. For Sourcing tests, 5V ≤ VO ≤ 10V. For Sinking tests, 0.5V ≤ VO ≤ 5V.
Note 26: Connected as Voltage Follower with 1.0V step input. Number specified is the slower of the positive and negative slew rates. Input referred, V+ = 10V and
RL = 100 kΩ connected to 5V. Amp excited with 1 kHz to produce VO = 2 VPP.
Note 27: Operation near absolute maximum limits will adversely affect reliability.
www.national.com
6
Typical Performance Characteristics
TA = 25˚C unless specified, Single Supply
Supply Current vs
Supply Voltage
Voltage Noise vs Frequency
DS012352-4
DS012352-3
2.7V PERFORMANCE
Offset Voltage vs Common
Mode Voltage @ 2.7V
Sinking Output vs
Output Voltage
DS012352-68
Gain and Phase vs
Capacitive Load @ 2.7V
Sourcing Output vs
Output Voltage
DS012352-20
Gain and Phase vs
Capacitive Load @ 2.7V
DS012352-22
Gain and Phase vs
Capacitive Load @ 2.7V
DS012352-23
7
DS012352-21
DS012352-24
www.national.com
3V PERFORMANCE
Voltage Noise vs Common
Mode Voltage @ 3V
Output Voltage vs Input
Voltage @ 3V
DS012352-25
Sourcing Output vs
Output Voltage
DS012352-26
Sinking Output vs
Output Voltage
DS012352-28
DS012352-27
Gain and Phase vs
Capacitive Load @ 3V
DS012352-29
Gain and Phase vs
Capacitive Load @ 3V
DS012352-30
Gain and Phase vs
Capacitive Load @ 3V
DS012352-31
www.national.com
Offset Voltage vs Common
Mode Voltage @ 3V
DS012352-32
8
5V PERFORMANCE
Voltage Noise vs Common
Mode Voltage @ 5V
Output Voltage vs
Input Voltage @ 5V
DS012352-33
Sourcing Output vs
Output Voltage
Offset Voltage vs Common
Mode Voltage @ 5V
DS012352-34
Sinking Output vs
Output Voltage
DS012352-36
Gain and Phase vs
Capacitive Load @ 5V
DS012352-35
Gain and Phase vs
Capacitive Load @ 5V
DS012352-37
Gain and Phase vs
Capacitive Load @ 5V
DS012352-38
Non-Inverting Small Signal
Pulse Response at 5V
DS012352-41
DS012352-39
Non-Inverting Small Signal
Pulse Response at 5V
DS012352-40
Non-Inverting Small Signal
Pulse Response at 5V
DS012352-42
DS012352-43
9
Non-Inverting Large Signal
Pulse Response at 5V
DS012352-44
www.national.com
5V PERFORMANCE
(Continued)
Non-Inverting Large Signal
Pulse Response at 5V
Non-Inverting Large Signal
Pulse Response at 5V
DS012352-45
Inverting Small Signal
Pulse Response at 5V
DS012352-46
Inverting Small Signal
Pulse Response at 5V
Inverting Small Signal
Pulse Response at 5V
DS012352-48
DS012352-47
Inverting Large Signal
Pulse Response at 5V
DS012352-49
Inverting Large Signal
Pulse Response at 5V
DS012352-50
Inverting Large Signal
Pulse Response at 5V
DS012352-51
DS012352-52
10V PERFORMANCE
Voltage Noise vs Common
Mode Voltage @ 10V
Output Voltage vs
Input Voltage @ 10V
DS012352-53
www.national.com
Offset Voltage vs Common
Mode Voltage @ 10V
DS012352-54
10
DS012352-55
10V PERFORMANCE
(Continued)
Sourcing Output vs
Output Voltage
Sinking Output vs
Output Voltage
Gain and Phase vs
Capacitive Load @ 10V
DS012352-56
Gain and Phase vs
Capacitive Load @ 10V
DS012352-57
Gain and Phase vs
Capacitive Load @ 10V
DS012352-58
Non-Inverting Small Signal
Pulse Response at 10V
DS012352-61
DS012352-59
Non-Inverting Large Signal
Pulse Response at 10V
DS012352-60
Inverting Small Signal
Pulse Response at 10V
DS012352-62
DS012352-63
Inverting Large Signal
Pulse Response at 10V
DS012352-64
integrity. The Tiny amp can also be placed next to the signal
destination, such as a buffer for the reference of an analog to
digital converter.
Simplified Board Layout. The Tiny amp can simplify board
layout in several ways. First, by placing an amp where amps
are needed, instead of routing signals to a dual or quad device, long pc traces may be avoided.
Application Information
1.0 Benefits of the LMC7111
Tiny Amp
Size. The small footprint of the SOT 23-5 packaged Tiny
amp, (0.120 x 0.118 inches, 3.05 x 3.00 mm) saves space on
printed circuit boards, and enable the design of smaller electronic products. Because they are easier to carry, many customers prefer smaller and lighter products.
Height. The height (0.056 inches, 1.43 mm) of the Tiny amp
makes it possible to use it in PCMCIA type III cards.
By using multiple Tiny amps instead of duals or quads, complex signal routing and possibly crosstalk can be reduced.
DIPs available for prototyping. LMC7111 amplifiers packaged in conventional 8-pin dip packages can be used for
prototyping and evaluation without the need to use surface
mounting in early project stages.
Signal Integrity. Signals can pick up noise between the signal source and the amplifier. By using a physically smaller
amplifier package, the Tiny amp can be placed closer to the
signal source, reducing noise pickup and increasing signal
11
www.national.com
Application Information
(Continued)
Low Supply Current. The typical 25 µA supply current of
the LMC7111 extends battery life in portable applications,
and may allow the reduction of the size of batteries in some
applications.
Wide Voltage Range. The LMC7111 is characterized at
2.7V, 3V, 3.3V, 5V and 10V. Performance data is provided at
these popular voltages. This wide voltage range makes the
LMC7111 a good choice for devices where the voltage may
vary over the life of the batteries.
DS012352-12
FIGURE 2. Resistive Isolation
of a 330 pF Capacitive Load
2.0 Input Common Mode
Voltage Range
The LMC7111 does not exhibit phase inversion when an input voltage exceeds the negative supply voltage.
4.0 Compensating for Input
Capacitance when Using Large
Value Feedback Resistors
When using very large value feedback resistors, (usually
> 500 kΩ) the large feed back resistance can react with the
input capacitance due to transducers, photodiodes, and circuit board parasitics to reduce phase margins.
The effect of input capacitance can be compensated for by
adding a feedback capacitor. The feedback capacitor (as in
Figure 3), Cf is first estimated by:
The absolute maximum input voltage is 300 mV beyond either rail at room temperature. Voltages greatly exceeding
this maximum rating can cause excessive current to flow in
or out of the input pins, adversely affecting reliability.
Applications that exceed this rating must externally limit the
maximum input current to ± 5 mA with an input resistor as
shown in Figure 1.
or
R1 CIN ≤ R2 Cf
which typically provides significant overcompensation.
Printed circuit board stray capacitance may be larger or
smaller than that of a breadboard, so the actual optimum
value for CF may be different. The values of CF should be
checked on the actual circuit. (Refer to the LMC660 quad
CMOS amplifier data sheet for a more detailed discussion.)
DS012352-14
FIGURE 1. RI Input Current Protection for
Voltages Exceeding the Supply Voltage
3.0 Capacitive Load Tolerance
The LMC7111 can typically directly drive a 300 pF load with
VS = 10V at unity gain without oscillating. The unity gain follower is the most sensitive configuration. Direct capacitive
loading reduces the phase margin of op-amps. The combination of the op-amp’s output impedance and the capacitive
load induces phase lag. This results in either an underdamped pulse response or oscillation.
Capacitive load compensation can be accomplished using
resistive isolation as shown in Figure 2. This simple technique is useful for isolating the capacitive input of multiplexers and A/D converters.
DS012352-13
FIGURE 3. Cancelling the Effect of Input Capacitance
5.0 Output Swing
The output of the LMC7111 will go to within 100 mV of either
power supply rail for a 10 kΩ load and to 20 mV of the rail for
a 100 kΩ load. This makes the LMC7111 useful for driving
transistors which are connected to the same power supply.
By going very close to the supply, the LMC7111 can turn the
transistors all the way on or all the way off.
6.0 Biasing GaAs RF Amplifiers
The capacitive load capability, low current draw, and small
size of the SOT23-5 LMC7111 make it a good choice for providing a stable negative bias to other integrated circuits.
The very small size of the LMC7111 and the LM4040 reference take up very little board space.
www.national.com
12
Application Information
(Continued)
DS012352-17
CF and Risolation prevent oscillations when driving capacitive loads.
FIGURE 4. Stable Negative Bias
The small size of the LMC7111 allows it to be placed close to
the reference input. The low supply current (25 µA typical)
saves power.
For A-to-D reference inputs which require higher accuracy
and lower offset voltage, please see the LMC6462
datasheet. The LMC6462 has performance similar to the
LMC7111. The LMC6462 is available in two grades with reduced input voltage offset.
7.0 Reference Buffer for A-to-D Converters
The LMC7111 can be used as a voltage reference buffer for
analog-to-digital converters. This works best for A-to-D converters whose reference input is a static load, such as dual
slope integrating A-to-Ds. Converters whose reference input
is a dynamic load (the reference current changes with time)
may need a faster device, such as the LMC7101 or the
LMC7131.
DS012352-18
10.0 Additional SOT23-5 Tiny
Devices
National Semiconductor has additional parts available in the
space saving SOT23 Tiny package, including amplifiers,
voltage references, and voltage regulators. These devices
include —
LMC7101 1 MHz gain-bandwidth rail-to-rail input and output amplifier — high input impedance and high
gain, 700 µA typical current 2.7V, 3V, 5V and 15V
specifications.
LM7131
Tiny Video amp with 70 MHz gain bandwidth.
Specified at 3V, 5V and ± 5V supplies.
LMC7211 Comparator in a tiny package with rail-to-rail input and push-pull output. Typical supply current
of 7 µA. Typical propagation delay of 7 µs. Specified at 2.7V, 5V and 15V supplies.
LMC7221 Comparator with an open drain output for use in
mixed voltage systems. Similar to the LMC7211,
8.0 Dual and Quad Devices with Similar Performance
The LMC6462 and LMC6464 are dual and quad devices with
performance similar to the LMC7111. They are available in
both conventional through-hole and surface mount packaging. Please see the LMC6462/4 datasheet for details.
9.0 SPICE Macromodel
A SPICE macromodel is available for the LMC7111. This
model includes simulation of:
•
•
•
•
Input common-mode voltage range
Frequency and transient response
Quiescent and dynamic supply current
Output swing dependence on loading conditions and
many more characteristics as listed on the macro model
disk. Contact your local National Semiconductor sales office to obtain an operational amplifier spice model library
disk.
13
www.national.com
Application Information
LP2980
(Continued)
except the output can be used with a pull-up resistor to a voltage different than the supply voltage.
Micropower SOT 50 mA Ultra Low-Dropout
Regulator.
LM4040
Precision micropower shunt voltage reference.
Fixed voltages of 2.5000V, 4.096V, 5.000V,
8.192V and 10.000V.
LM4041
Precision micropower shunt voltage reference
1.225V and adjustable.
Contact your National Semiconductor representative for the
latest information.
www.national.com
14
SOT-23-5 Tape and Reel Specification
TAPE FORMAT
Tape Section
# Cavities
Cavity Status
Cover Tape Status
Leader
0 (min)
Empty
Sealed
(Start End)
75 (min)
Empty
Sealed
Carrier
3000
Filled
Sealed
1000
Filled
Sealed
Trailer
125 (min)
Empty
Sealed
(Hub End)
0 (min)
Empty
Sealed
TAPE DIMENSIONS
DS012352-15
8 mm
Tape Size
0.130
0.124
0.130
0.126
0.138 ± 0.002
0.055 ± 0.004
0.157
0.315 ± 0.012
(3.3)
(3.15)
(3.3)
(3.2)
(3.5 ± 0.05)
(1.4 ± 0.11)
(4)
(8 ± 0.3)
DIM A
DIM Ao
DIM B
DIM Bo
DIM F
DIM Ko
DIM P1
DIM W
15
www.national.com
SOT-23-5 Tape and Reel Specification
(Continued)
REEL DIMENSIONS
DS012352-16
8 mm
Tape Size
www.national.com
7.00
0.059 0.512 0.795 2.165
330.00
1.50
A
B
0.331 + 0.059/−0.000
0.567
W1+ 0.078/−0.039
8.40 + 1.50/−0.00
14.40
W1 + 2.00/−1.00
W1
W2
W3
13.00 20.20 55.00
C
D
N
16
Physical Dimensions
inches (millimeters) unless otherwise noted
*Suffix indicates number of units. See Ordering Information on first page.
5-Pin SOT Package
Order Package Number LMC7111BIM5*
NS Package Number MA05A
17
www.national.com
LMC7111 Tiny CMOS Operational Amplifier with Rail-to-Rail Input and Output
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
8-Pin Molded DIP
8-Lead (0.300" Wide) Molded Dual-In-Line Package
Order Package Number LMC7111AIN or LMC7111BIN
NS Package Number N08E
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
National Semiconductor
Corporation
Americas
Tel: 1-800-272-9959
Fax: 1-800-737-7018
Email: [email protected]
www.national.com
National Semiconductor
Europe
Fax: +49 (0) 1 80-530 85 86
Email: [email protected]
Deutsch Tel: +49 (0) 1 80-530 85 85
English Tel: +49 (0) 1 80-532 78 32
Français Tel: +49 (0) 1 80-532 93 58
Italiano Tel: +49 (0) 1 80-534 16 80
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
National Semiconductor
Asia Pacific Customer
Response Group
Tel: 65-2544466
Fax: 65-2504466
Email: [email protected]
National Semiconductor
Japan Ltd.
Tel: 81-3-5639-7560
Fax: 81-3-5639-7507
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.