TI1 LMV552MMX/NOPB Lmv551/lmv552/lmv554 3 mhz, micropower rro amplifier Datasheet

LMV551, LMV552
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SNOSAQ5G – FEBRUARY 2007 – REVISED FEBRUARY 2013
LMV551/LMV552/LMV554 3 MHz, Micropower RRO Amplifiers
Check for Samples: LMV551, LMV552
FEATURES
DESCRIPTION
•
•
•
•
•
•
•
•
The LMV551/LMV552/LMV554 are high performance,
low power operational amplifiers implemented with
TI’s advanced VIP50 process. They feature 3 MHz of
bandwidth while consuming only 37 μA of current per
amplifier, which is an exceptional bandwidth to power
ratio in this op amp class. These amplifiers are unity
gain stable and provide an excellent solution for low
power applications requiring a wide bandwidth.
1
2
•
•
(Typical 5V Supply, Unless Otherwise Noted.)
Guaranteed 3V and 5.0V Performance
High Unity Gain Bandwidth 3 MHz
Supply Current (Per Amplifier) 37 µA
CMRR 93 dB
PSRR 90 dB
Slew Rate 1 V/µs
Output Swing with 100 kΩ Load 70 mV From
Rail
Total Harmonic Distortion 0.003% @ 1 kHz, 2
kΩ
Temperature Range −40°C to 125°C
APPLICATIONS
•
•
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Active Filter
Portable Equipment
Automotive
Battery Powered Systems
Sensors and Instrumentation
The LMV551/LMV552/LMV554 have a rail-to-rail
output stage and an input common mode range that
extends below ground.
The LMV551/LMV552/LMV554 have an operating
supply voltage range from 2.7V to 5.5V. These
amplifiers can operate over a wide temperature range
(−40°C to 125°C) making them a great choice for
automotive applications, sensor applications as well
as portable instrumentation applications. The
LMV551 is offered in the ultra tiny 5-Pin SC70 and 5Pin SOT-23 package. The LMV552 is offered in an 8Pin VSSOP package. The LMV554 is offered in the
14-Pin TSSOP.
Typical Application
120
120
100
R2
100 k:
+
VIN
-
RB1
V
+
+
-
+
RB2
PHASE
VOUT
100
80
80
GAIN (dB)
CC1
R1
1 k:
60
60
GAIN
40
40
20
20
PHASE (°)
CF
0
0
-20
-20
VS = 5V
-40
100
1k
10k
100k
1M
-40
10M
FREQUENCY (Hz)
Figure .
Figure 1. Open Loop Gain and Phase vs.
Frequency
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007–2013, Texas Instruments Incorporated
LMV551, LMV552
SNOSAQ5G – FEBRUARY 2007 – REVISED FEBRUARY 2013
Absolute Maximum Ratings
ESD Tolerance
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(1) (2)
(3)
Human Body Model
LMV551/LMV552/LMV554
2 KV
Machine Model
LMV551
100V
LMV552/LMV554
250V
VIN Differential (@ V+ = 5V)
±2.5V
Supply Voltage (V+ - V−)
6V
V+ +0.3V, V− −0.3V
Voltage at Input/Output pins
−65°C to 150°C
Storage Temperature Range
Junction Temperature
(4)
150°C
Soldering Information
Infrared or Convection (20 sec)
235°C
Wave Soldering Lead Temp. (10 sec)
260°C
(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 Tables.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office / Distributors for
availability and specifications.
Human Body Model, applicable std. MIL-STD-883, Method 3015.7. Machine Model, applicable std. JESD22-A115-A (ESD MM std. of
JEDEC) Field-Induced Charge-Device Model, applicable std. JESD22-C101-C (ESD FICDM std. of JEDEC).
The maximum power dissipation is a function of TJ(MAX), θJA. The maximum allowable power dissipation at any ambient temperature is
PD = (TJ(MAX) - TA)/ θJA. All numbers apply for packages soldered directly onto a PC board.
(2)
(3)
(4)
Operating Ratings
Temperature Range
(1)
(2)
−40°C to 125°C
Supply Voltage (V – V−)
+
2.7V to 5.5V
Package Thermal Resistance (θJA (2))
5-Pin SC70
456°C/W
5-Pin SOT-23
234°C/W
8-Pin VSSOP
235°C/W
14-Pin TSSOP
160°C/W
(1)
(2)
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 Tables.
The maximum power dissipation is a function of TJ(MAX), θJA. The maximum allowable power dissipation at any ambient temperature is
PD = (TJ(MAX) - TA)/ θJA. All numbers apply for packages soldered directly onto a PC board.
3V Electrical Characteristics
Unless otherwise specified, all limits are guaranteed for TA = 25°C, V+ = 3V, V− = 0V, VCM = V+/2 = VO. Boldface limits apply
at the temperature extremes. (1)
Symbol
Parameter
VOS
Input Offset Voltage
TC VOS
Input Offset Average Drift
(1)
(2)
(3)
2
Conditions
Min
(2)
Typ
Max
Units
1
3
4.5
mV
(3)
3.3
(2)
μV/°C
Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under
conditions of internal self-heating where TJ > TA.
Limits are 100% production tested at 25°C. Limits over the operating temperature range are guaranteed through correlations using
statistical quality control (SQC) method.
Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested and are not guaranteed on
shipped production material.
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3V Electrical Characteristics (continued)
Unless otherwise specified, all limits are guaranteed for TA = 25°C, V+ = 3V, V− = 0V, VCM = V+/2 = VO. Boldface limits apply
at the temperature extremes. (1)
Symbol
Parameter
Conditions
Input Bias Current
IOS
Input Offset Current
CMRR
Common Mode Rejection Ratio
0V ≤ VCM 2.0V
PSRR
Power Supply Rejection Ratio
3.0 ≤ V+ ≤ 5V,
VCM = 0.5V
2.7 ≤ V+ ≤ 5.5V,
VCM = 0.5V
CMVR
Input Common-Mode Voltage
Range
CMRR ≥ 68 dB
CMRR ≥ 60 dB
AVOL
Large Signal Voltage Gain
0.4 ≤ VO ≤ 2.6,
RL = 100 kΩ to V+/2
LMV551/LMV552
80
78
LMV554
78
76
LMV551/LMV552
80
78
LMV554
78
76
Output Swing Low
ISC
Output Short Circuit Current
nA
20
nA
92
92
dB
92
0
0
LMV551/LMV552
81
78
LMV554
79
77
dB
2.1
2.1
dB
71
68
80
100
120
RL = 100 kΩ to V+/2
50
65
77
RL = 10 kΩ to V+/2
95
110
130
Sourcing
V
90
85
(5)
mV from
rail
10
(5)
mA
25
Slew Rate
AV = +1,
10% to 90%
Φm
Phase Margin
RL = 10 kΩ, CL = 20 pF
GBW
Gain Bandwidth Product
en
Input-Referred Voltage Noise
(4)
(5)
(6)
38
1
RL = 10 kΩ to V+/2
SR
Total Harmonic Distortion
20
48
58
Supply Current per Amplifier
THD
Units
(2)
40
IS
Input-Referred Current Noise
Max
RL = 100 kΩ to V+/2
Sinking
in
Typ
(3)
74
72
0.4 ≤ VO ≤ 2.6, RL = 10 kΩ to V+/2
Output Swing High
(2)
(4)
IB
VO
Min
34
1
(6)
42
52
μA
V/μs
75
Deg
3
MHz
f = 100 kHz
70
f = 1 kHz
70
f = 100 kHz
0.1
f = 1 kHz
0.15
f = 1 kHz, AV = 2, RL = 2 kΩ
0.003
nV/
pA/
%
Positive current corresponds to current flowing into the device.
The part is not short circuit protected and is not recommended for operation with heavy resistive loads.
Slew rate is the average of the rising and falling slew rates.
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5V Electrical Characteristics
Unless otherwise specified, all limits are guaranteed for TA = 25°C, V+ = 5V, V− = 0V, VCM = V+/2 = VO. Boldface limits apply
at the temperature extremes.
Symbol
Parameter
Conditions
Min
(1)
Typ
Max
Units
1
3.0
4.5
mV
(2)
VOS
Input Offset Voltage
TC VOS
Input Offset Average Drift
IB
Input Bias Current
IOS
Input Offset Current
CMRR
Common Mode Rejection Ratio
0 ≤ VCM ≤ 4.0V
76
74
93
PSRR
Power Supply Rejection Ratio
3V ≤ V+ ≤ 5V to VCM = 0.5V
78
75
90
2.7V ≤ V+ ≤ 5.5V to VCM = 0.5V
78
75
90
CMRR ≥ 68 dB
CMRR ≥ 60 dB
0
0
CMVR
AVOL
VO
Input Common-Mode Voltage
Range
Large Signal Voltage Gain
Output Swing High
Output Swing Low
ISC
Output Short Circuit Current
(1)
μV/°C
3.3
(3)
+
20
38
nA
1
20
nA
dB
dB
4.1
4.1
0.4 ≤ VO ≤ 4.6, RL = 100 kΩ to V /2
78
75
90
0.4 ≤ VO ≤ 4.6, RL = 10 kΩ to V+/2
75
72
80
dB
RL = 100 kΩ to V+/2
70
92
122
RL = 10 kΩ to V+/2
125
155
210
RL = 100 kΩ to V+/2
60
70
82
RL = 10 kΩ to V+/2
110
130
155
Sourcing
Sinking
(4)
(4)
10
mV from
rail
mA
25
IS
Supply Current Per Amplifier
SR
Slew Rate
AV = +1, VO = 1 VPP
10% to 90% (5)
1
Φm
Phase Margin
RL = 10 kΩ, CL = 20 pF
75
Deg
GBW
Gain Bandwidth Product
3
MHz
en
Input-Referred Voltage Noise
in
Input-Referred Current Noise
THD
(1)
(2)
(3)
(4)
(5)
4
Total Harmonic Distortion
37
V
f = 100 kHz
70
f = 1 kHz
70
f = 100 kHz
0.1
f = 1 kHz
0.15
f = 1 kHz, AV = 2, RL = 2 kΩ
0.003
46
54
μA
V/μs
nV/
pA/
%
Limits are 100% production tested at 25°C. Limits over the operating temperature range are guaranteed through correlations using
statistical quality control (SQC) method.
Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested and are not guaranteed on
shipped production material.
Positive current corresponds to current flowing into the device.
The part is not short circuit protected and is not recommended for operation with heavy resistive loads.
Slew rate is the average of the rising and falling slew rates.
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CONNECTION DIAGRAM
1
8
+
V
A
-IN A
2
-
OUT A
7
OUT B
+IN A
3
6
B
+
V
Figure 2. 5-Pin SC70/ SOT-23
Top View
-
4
2
+
3
12
+
4
11
+
5
10
-
6
9
IN A
V
-IN B
IN B
IN B
-
A
- +
- +
B
5
+IN B
Figure 3. 8-Pin VSSOP
Top View
13
-
IN A
+
14
1
OUT B
7
D
+
-
OUT A
+ -
Product Folder Links: LMV551 LMV552
IN D
-
IN D
+
-
V
IN C
IN C
+
-
C
8
OUT C
Figure 4. 14-Pin TSSOP
Top View
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OUT D
5
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TYPICAL CHARACTERISTICS
Open Loop Gain and Phase with Capacitive Load
Open Loop Gain and Phase with Resistive Load
158
140
120
RL = 100 k: 135
120
135
100
113
100
113
90
80
20 pF
50 pF
60
68
100 pF
45
PHASE
23
20
20 pF
100 pF
50 pF
0
-20
100
10k
1k
100k
1M
90
68
60
GAIN
45
40
23
20 VS = +3V
RL = 100 k:
0
CL = 20 pF
-20
10k
100
1k
0
-23
10M
0
100k
Figure 5.
Figure 6.
Open Loop Gain and Phase with Resistive Load
Open Loop Gain and Phase with Resistive Load
140
158
140
158
120
135
120
135
100
113
100
90
80
113
60 GAIN
68
40
45
20 VS = 3V
0 RL = 10 k:
0
CL = 20 pF
-20
100
1k
23
10k
100k
1M
GAIN (dB)
80
PHASE (°)
PHASE
60
PHASE
68
45
40
20
23
VS = 5V
0 RL = 100 k:
CL = 20 pF
-20
100
1k
-23
10M
0
10k
100k
1M
Figure 8.
Open Loop Gain and Phase with Resistive Load
Slew Rate
vs.
Supply voltage
158
1.1
120
135
1.0
100
113
90
60
68
0
GAIN
45
VS = 5V
23
RL = 10 k:
0
PHASE (°)
PHASE
80
SLEW RATE (V/Ps)
140
20
-23
10M
FREQUENCY (Hz)
Figure 7.
40
90
GAIN
FREQUENCY (Hz)
GAIN (dB)
-23
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
GAIN (dB)
1M
PHASE (°)
GAIN
40
158
PHASE (°)
PHASE
80
GAIN (dB)
VS = +5V
PHASE (°)
GAIN (dB)
140
RISING EDGE
0.9
0.8
0.7
FALLING EDGE
0.6
0.5
CL = 20 pF
-20
100
1k
10k
100k
1M
-23
10M
0.4
Figure 9.
6
3
3.25 3.5 3.75
4
4.25 4.5 4.75
5
VS (V)
FREQUENCY (Hz)
Figure 10.
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TYPICAL CHARACTERISTICS (continued)
Small Signal Transient Response
Large Signal Transient Response
0.015
1.5
0.01
1
0.5
VOUT (V)
VOUT (V)
0.005
VS = 5V
0
CL = 50 pF
VIN = 20 mVPP, 20 kHz
VS = 5V
0
-0.005
-0.5
-0.01
-1
-0.015
CL = 15 pF, AV = +1
VIN = 2 VPP, 20 kHz
-1.5
0
20
40
60
80
100
0
20
40
TIME (Ps)
80
Figure 11.
Figure 12.
Small Signal Transient Response
Input Referred Noise
vs.
Frequency
0.015
100
1000
INPUT REFERRED NOISE
0.01
0.005
VOUT (V)
60
TIME (Ps)
0
VS = 5V
CL = 15 pF
-0.005
VIN = 20 mVPP, 20 kHz
-0.01
VOLTAGE nV/ Hz
100
10
1
0.1
CURRENT pA/ Hz
0
-0.015
0
20
40
60
80
0.1
1
10
TIME (Ps)
100
1k
10k
FREQUENCY (Hz)
Figure 13.
Figure 14.
THD+N
vs.
Amplitude @ 3V
THD+N
vs.
Amplitude @ 5V
1.00
1.00
THD+N (%)
0.10
THD+N (%)
0.10
RL = 10 k:
0.01
RL = 10 k:
0.01
VS = 3V
VS = 5V
AV = +2
RL = 100 k:
VIN = 1 kHz SINE WAVE
0.00
0.01
0.1
1
10
AV = +2
VIN = 1 kHz SINE WAVE
0.00
0.01
0.1
VOUT (VPP)
RL = 100 k:
1
10
VOUT (VPP)
Figure 15.
Figure 16.
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TYPICAL CHARACTERISTICS (continued)
THD+N
vs.
Amplitude
THD+N
vs.
Amplitude
1
1
VS = 3V
VS = 5V
AV = +2
AV = +2
VOUT = 1 VPP
VOUT = 2 VPP
THD+N (%)
0.1
THD+N (%)
0.1
RL = 10 k:
0.01
RL = 10 k:
0.01
RL = 100 k:
RL = 100 k:
0.001
0.001
10
100
1k
10k
100k
10
100
FREQUENCY (Hz)
1k
10k
100k
FREQUENCY (Hz)
Figure 17.
Figure 18.
Supply Current
vs.
Supply Voltage
VOS
vs.
VCM
2
50
VS = 3V
PER CHANNEL
1.5
45
125°C
1
25°C
VOS (mV)
IS (PA)
40
35
-40°C
0.5
0
-40qC
25qC
-0.5
30
-1
25
-1.5
125qC
20
2.7
3.4
4.1
4.8
-2
0
5.5
0.5
1
2
1.5
1
1
0.5
0.5
VOS (mV)
VOS (mV)
5.5
VOS
vs.
Supply Voltage
0
-40qC
25qC
-0.5
0
-1
-1
-1.5
-1.5
2
25qC
-40qC
-0.5
125qC
125qC
3
4
5
-2
2.7
VCM (V)
3.4
4.1
VS (V)
Figure 21.
8
4.8
VOS
vs.
VCM
VS = 5V
1
2.5
Figure 20.
2
0
2
Figure 19.
1.5
-2
1.5
VCM (V)
VS (V)
Figure 22.
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TYPICAL CHARACTERISTICS (continued)
IBIAS
vs.
VCM
26
26
24
24
IBIAS
vs.
VCM
125°C
22
25°C
25°C
125°C
20
IBIAS (nA)
IBIAS (nA)
22
18
16
20
18
16
-40°C
-40°C
14
14
12
12
VS = 5V
VS = 3V
10
0
0.5
1
1.5
2
10
2.5
0
1
2
3
4
5
VCM (V)
VCM (V)
Figure 23.
Figure 24.
IBIAS
vs.
Supply Voltage
Positive Output Swing
vs.
Supply Voltage
180
26
125°C
160
24
VOUT FROM RAIL (mV)
125°C
22
IBIAS (nA)
25°C
20
18
16
-40° C
14
140
25°C
120
100
80
-40°C
60
40
12
RL = 10 k:
10
2.5
3
3.5
4
4.5
20
5.5
5
3
3.5
4
Figure 26.
Negative Output Swing
vs.
Supply Voltage
Positive Output Swing
vs.
Supply Voltage
100
90
90
80
VOUT FROM RAIL (mV)
VOUT FROM RAIL (mV)
Figure 25.
100
125°C
70
25°C
60
50
40
80
20
25°C
60
50
40
3.5
-40°C
30
RL = 100 k:
3
5
125°C
70
-40°C
30
4.5
VS (V)
VS (V)
RL = 100 k:
4
4.5
5
20
3
3.5
4
4.5
5
VS (V)
VS (V)
Figure 27.
Figure 28.
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TYPICAL CHARACTERISTICS (continued)
Negative Output Swing
vs.
Supply Voltage
180
VOUT FROM RAIL (mV)
160
125°C
140
25°C
120
100
80
-40°C
60
40
RL = 10 k:
20
3
3.5
4
4.5
5
VS (V)
Figure 29.
10
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APPLICATIONS INFORMATION
ADVANTAGES OF THE LMV551/LMV552/LMV554
Low Voltage and Low Power Operation
The LMV551/LMV552/LMV554 have performance guaranteed at supply voltages of 3V and 5V and are
guaranteed to be operational at all supply voltages between 2.7V and 5.5V. For this supply voltage range, the
LMV551/LMV552/LMV554 draw the extremely low supply current of less than 37 μA per amp.
Wide Bandwidth
The bandwidth to power ratio of 3 MHz to 37 μA per amplifier is one of the best bandwidth to power ratios ever
achieved. This makes these devices ideal for low power signal processing applications such as portable media
players and instrumentation.
Low Input Referred Noise
The LMV551/LMV552/LMV554 provide a flatband input referred voltage noise density of 70 nV/
, which is
significantly better than the noise performance expected from an ultra low power op amp. They also feature the
exceptionally low 1/f noise corner frequency of 4 Hz. This noise specification makes the
LMV551/LMV552/LMV554 ideal for low power applications such as PDAs and portable sensors.
Ground Sensing and Rail-to-Rail Output
The LMV551/LMV552/LMV554 each have a rail-to-rail output stage, which provides the maximum possible
output dynamic range. This is especially important for applications requiring a large output swing. The input
common mode range includes the negative supply rail which allows direct sensing at ground in a single supply
operation.
Small Size
The small footprints of the LMV551/LMV552/LMV554 packages save space on printed circuit boards, and enable
the design of smaller and more compact electronic products. Long traces between the signal source and the op
amp make the signal path susceptible to noise. By using a physically smaller package, the amplifiers can be
placed closer to the signal source, reducing noise pickup and enhancing signal integrity
STABILITY OF OP AMP CIRCUITS
Stability and Capacitive Loading
As seen in the Phase Margin vs. Capacitive Load graph, the phase margin reduces significantly for CL greater
than 100 pF. This is because the op amp is designed to provide the maximum bandwidth possible for a low
supply current. Stabilizing them for higher capacitive loads would have required either a drastic increase in
supply current, or a large internal compensation capacitance, which would have reduced the bandwidth of the op
amp. Hence, if the LMV551/LMV552/LMV554 are to be used for driving higher capacitive loads, they will have to
be externally compensated.
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11
LMV551, LMV552
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GAIN
SNOSAQ5G – FEBRUARY 2007 – REVISED FEBRUARY 2013
STABLE
ROC ± 20 dB/decade
UNSTABLE
ROC = 40 dB/decade
0
FREQUENCY (Hz)
Figure 30. Gain vs. Frequency for an Op Amp
An op amp, ideally, has a dominant pole close to DC, which causes its gain to decay at the rate of 20 dB/decade
with respect to frequency. If this rate of decay, also known as the rate of closure (ROC), remains the same until
the op amp’s unity gain bandwidth, the op amp is stable. If, however, a large capacitance is added to the output
of the op amp, it combines with the output impedance of the op amp to create another pole in its frequency
response before its unity gain frequency (Figure 30). This increases the ROC to 40 dB/ decade and causes
instability.
In such a case a number of techniques can be used to restore stability to the circuit. The idea behind all these
schemes is to modify the frequency response such that it can be restored to an ROC of 20 dB/decade, which
ensures stability.
In the Loop Compensation
Figure 31 illustrates a compensation technique, known as ‘in the loop’ compensation, that employs an RC
feedback circuit within the feedback loop to stabilize a non-inverting amplifier configuration. A small series
resistance, RS, is used to isolate the amplifier output from the load capacitance, CL, and a small capacitance, CF,
is inserted across the feedback resistor to bypass CL at higher frequencies.
VIN
+
ROUT
-
RS
CL
RL
CF
RF
RIN
Figure 31. In the Loop Compensation
The values for RS and CF are decided by ensuring that the zero attributed to CF lies at the same frequency as the
pole attributed to CL. This ensures that the effect of the second pole on the transfer function is compensated for
by the presence of the zero, and that the ROC is maintained at 20 dB/decade. For the circuit shown in Figure 31
the values of RS and CF are given by Equation 1. Values of RS and CF required for maintaining stability for
different values of CL, as well as the phase margins obtained, are shown in Table 1. RF, RIN, and RL are to be 10
kΩ, while ROUT is 340Ω.
12
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SNOSAQ5G – FEBRUARY 2007 – REVISED FEBRUARY 2013
RS = ROUTRIN
RF
§ RF + 2RIN
¨
CLROUT
¨ R2
F
©
§
¨
¨
©
§
¨
¨
©
§
1
CF = ¨¨1 +
ACL
©
(1)
Table 1. Phase Margins
CL (pF)
RS (Ω)
CF (pF)
Phase Margin (°)
50
340
8
47
100
340
15
42
150
340
22
40
Although this methodology provides circuit stability for any load capacitance, it does so at the price of bandwidth.
The closed loop bandwidth of the circuit is now limited by RF and CF.
Compensation by External Resistor
In some applications it is essential to drive a capacitive load without sacrificing bandwidth. In such a case, in the
loop compensation is not viable. A simpler scheme for compensation is shown in Figure 32. A resistor, RISO, is
placed in series between the load capacitance and the output. This introduces a zero in the circuit transfer
function, which counteracts the effect of the pole formed by the load capacitance and ensures stability. The value
of RISO to be used should be decided depending on the size of CL and the level of performance desired. Values
ranging from 5Ω to 50Ω are usually sufficient to ensure stability. A larger value of RISO will result in a system with
less ringing and overshoot, but will also limit the output swing and the short circuit current of the circuit.
Figure 32. Compensation by Isolation Resistor
TYPICAL APPLICATION
ACTIVE FILTERS
With a wide unity gain bandwidth of 3 MHz, low input referred noise density and a low power supply current, the
LMV551/LMV552/LMV554 are well suited for low-power filtering applications. Active filter topologies, such as the
Sallen-Key low pass filter shown in Figure 33, are very versatile, and can be used to design a wide variety of
filters (Chebyshev, Butterworth or Bessel). The Sallen-Key topology, in particular, can be used to attain a wide
range of Q, by using positive feedback to reject the undesired frequency range.
In the circuit shown in Figure 33, the two capacitors appear as open circuits at lower frequencies and the signal
is simply buffered to the output. At high frequencies the capacitors appear as short circuits and the signal is
shunted to ground by one of the capacitors before it can be amplified. Near the cut-off frequency, where the
impedance of the capacitances is on the same order as RG and RF, positive feedback through the other capacitor
allows the circuit to attain the desired Q.
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13
LMV551, LMV552
SNOSAQ5G – FEBRUARY 2007 – REVISED FEBRUARY 2013
www.ti.com
C
2
m R
R
+
VIN
VO
C
-
RF
RG
Figure 33. Sallen-Key Filter
14
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SNOSAQ5G – FEBRUARY 2007 – REVISED FEBRUARY 2013
REVISION HISTORY
Changes from Revision F (February 2013) to Revision G
•
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 14
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15
PACKAGE OPTION ADDENDUM
www.ti.com
11-Apr-2014
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LMV551MF/NOPB
ACTIVE
SOT-23
DBV
5
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
AF3A
LMV551MFX/NOPB
ACTIVE
SOT-23
DBV
5
3000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
AF3A
LMV551MG/NOPB
ACTIVE
SC70
DCK
5
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
A94
LMV551MGX/NOPB
ACTIVE
SC70
DCK
5
3000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
A94
LMV552MM/NOPB
ACTIVE
VSSOP
DGK
8
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
AH3A
LMV552MMX/NOPB
ACTIVE
VSSOP
DGK
8
3500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
AH3A
LMV554MT/NOPB
ACTIVE
TSSOP
PW
14
94
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
LMV55
4MT
LMV554MTX/NOPB
ACTIVE
TSSOP
PW
14
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
LMV55
4MT
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
(4)
11-Apr-2014
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
6-Nov-2015
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
LMV551MF/NOPB
SOT-23
LMV551MFX/NOPB
LMV551MG/NOPB
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
3.2
1.4
4.0
8.0
Q3
DBV
5
1000
178.0
8.4
SOT-23
DBV
5
3000
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
SC70
DCK
5
1000
178.0
8.4
2.25
2.45
1.2
4.0
8.0
Q3
LMV551MGX/NOPB
SC70
DCK
5
3000
178.0
8.4
2.25
2.45
1.2
4.0
8.0
Q3
LMV552MM/NOPB
VSSOP
DGK
8
1000
178.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
LMV552MMX/NOPB
VSSOP
DGK
8
3500
330.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
LMV554MTX/NOPB
TSSOP
PW
14
2500
330.0
12.4
6.95
5.6
1.6
8.0
12.0
Q1
Pack Materials-Page 1
3.2
B0
(mm)
PACKAGE MATERIALS INFORMATION
www.ti.com
6-Nov-2015
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LMV551MF/NOPB
SOT-23
DBV
5
1000
210.0
185.0
35.0
LMV551MFX/NOPB
SOT-23
DBV
5
3000
210.0
185.0
35.0
LMV551MG/NOPB
SC70
DCK
5
1000
210.0
185.0
35.0
LMV551MGX/NOPB
SC70
DCK
5
3000
210.0
185.0
35.0
LMV552MM/NOPB
VSSOP
DGK
8
1000
210.0
185.0
35.0
LMV552MMX/NOPB
VSSOP
DGK
8
3500
367.0
367.0
35.0
LMV554MTX/NOPB
TSSOP
PW
14
2500
367.0
367.0
35.0
Pack Materials-Page 2
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