Texas Instruments | LM8272 Dual RRIO, High Output Current & Unlimited Cap Load Op Amp in Miniature Package (Rev. F) | Datasheet | Texas Instruments LM8272 Dual RRIO, High Output Current & Unlimited Cap Load Op Amp in Miniature Package (Rev. F) Datasheet

Texas Instruments LM8272 Dual RRIO, High Output Current & Unlimited Cap Load Op Amp in Miniature Package (Rev. F) Datasheet
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LM8272
SNOS515F – OCTOBER 2000 – REVISED AUGUST 2015
LM8272 Dual RRIO, High Output Current & Unlimited Cap Load
Op Amp in Miniature Package
1 Features
3 Description
(VS = 12V, TA = 25°C, Typical values unless
specified).
1
•
•
•
•
•
•
•
•
•
•
GBWP 15MHz
Wide supply voltage range 2.5 V to 24 V
Slew rate 15 V/µs
Supply current/channel 0.95 mA
Cap load tolerance Unlimited
Output short circuit current ±13 0mA
Output current (1 V from rails) ±65 mA
Input common mode voltage 0.3 V beyond rails
Input voltage noise 15 nV/√Hz
Input current noise 1.4 pA/√Hz
2 Applications
•
•
•
•
TFT-LCD flat panel VCOM driver
A/D converter buffer
High side/low side sensing
Headphone amplifier
The LM8272 is a Rail-to-Rail input and output Op
Amp which can operate with a wide supply voltage
range. This device has high output current drive,
greater than Rail-to-Rail input common mode voltage
range, and unlimited capacitive load drive capability,
while requiring only 0.95mA/channel supply current. It
is specifically designed to handle the requirements of
flat panel TFT panel VCOM driver applications as well
as being suitable for other low power and medium
speed applications which require ease of use and
enhanced performance over existing devices.
Greater than Rail-to-Rail input common mode voltage
range with 50 dB of Common Mode Rejection allows
high side and low side sensing among many
applications without concerns for exceeding the range
and with no compromise in accuracy. An
exceptionally wide operating supply voltage range of
2.5 V to 24 V removes any concerns over
functionality under extreme conditions and offers
flexibility of use in multitude of applications. In
addition, most device parameters are insensitive to
power supply variations. This design enhancement is
yet another step in simplifying its usage.
The LM8272 is offered in the 8-pin VSSOP package.
Device Information(1)
PART NUMBER
LM8272
PACKAGE
VSSOP (8)
BODY SIZE (NOM)
3.00 mm × 3.00 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
Simplified Schematic
Large Signal Step Response
for Various Cap. Load
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM8272
SNOS515F – OCTOBER 2000 – REVISED AUGUST 2015
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Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
6.7
4
4
4
4
5
6
8
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
5V Electrical Characteristics .....................................
12V Electrical Characteristics ...................................
Typical Performance Characteristics ........................
Application and Implementation ........................ 14
7.1 Block Diagram and Operational Description
A) Input Stage: .........................................................
B) Output Stage: .....................................................
C) Output Voltage Swing Close to V−: ....................
Driving Capactive Loads: ........................................
Estimating the Output Voltage Swing .....................
Output Short Circuit Current and Dissipation
Issues:......................................................................
7.7 Other Application Hints: ..........................................
7.8 LM8272 Advantages: ..............................................
7.2
7.3
7.4
7.5
7.6
8
17
18
18
Device and Documentation Support.................. 19
8.1
8.2
8.3
8.4
9
14
15
15
16
16
Community Resources............................................
Trademarks .............................................................
Electrostatic Discharge Caution ..............................
Glossary ..................................................................
19
19
19
19
Mechanical, Packaging, and Orderable
Information ........................................................... 19
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision E (August 2014) to Revision F
Page
•
Changed pin 5 From: -IN B To: +IN B Non-Inverting Input B in the Pin Functions table ....................................................... 3
•
Changed pin 6 From: +IN B To: -IN B Inverting Input B in the Pin Functions table............................................................... 3
•
Moved "Storage temperature range" to the Absolute Maximum Ratings (1) (2) ........................................................................ 4
•
Changed Handling Ratings To: ESD Ratings ........................................................................................................................ 4
Changes from Revision D (March 2013) to Revision E
Page
•
Changed data sheet structure and organization. Added, updated, or renamed the following sections: Device
Information Table, Application and Implementation; Power Supply Recommendations; Mechanical, Packaging, and
Ordering Information. ............................................................................................................................................................. 1
•
Deleted TJ = 25°C................................................................................................................................................................... 5
•
Deleted TJ = 25°C .................................................................................................................................................................. 6
Changes from Revision C (March 2013) to Revision D
•
2
Page
Changed layout of National Data Sheet to TI format ........................................................................................................... 18
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5 Pin Configuration and Functions
8-Pin VSSOP
Top View
Pin Functions
PIN
I/O
DESCRIPTION
NUMBER
NAME
1
OUT A
O
Output A
2
-IN A
I
Inverting Input A
3
+IN A
I
Non-Inverting Input A
4
V-
I
Negative Supply
5
+IN B
I
Non-Inverting Input B
6
-IN B
I
Inverting Input B
7
OUT B
O
Output B
8
V+
I
Positive Supply
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6 Specifications
6.1 Absolute Maximum Ratings (1) (2)
over operating free-air temperature range (unless otherwise noted)
MIN
VIN Differential
Output Short Circuit Duration
MAX
UNIT
+/−10
V
See
(3) (4)
Supply Voltage (V+ - V−)
27
V
V+ +0.3, V− −0.3
V
+150
°C
+150
°C
Infrared or Convection (20 sec.)
235
°C
Wave Soldering (10 sec.)
260
°C
Voltage at Input/Output pins
Junction Temperature
(5)
−65
Storage temperature range, Tstg
Soldering Information:
(1)
(2)
(3)
(4)
(5)
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Rating indicate conditions for
which the device is intended to be functional, but specific performance is not ensured. For ensured specifications and the test
conditions, see the Electrical Characteristics.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
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 of 150°C.
Output short circuit duration is infinite for VS ≤ 6 V at room temperature and below. For VS > 6 V, allowable short circuit duration is 1.5
ms.
The maximum power dissipation is a function of TJ(max), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(max) - TA)/ RθJA. All numbers apply for packages soldered directly onto a PC board.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
(3)
Electrostatic discharge (1)
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins (2)
±2000
Machine Model (MM) (3)
±200
UNIT
V
Human body model, 1.5 kΩ in series with 100 pF. Machine Model, 0 Ω is series with 200 pF.
JEDEC document JEP155 states that 2000-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 200-V MM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
Supply Voltage (V+ - V−)
Operating Temperature Range (1)
(1)
NOM
MAX
UNIT
2.5
24
V
−40
+85
°C
The maximum power dissipation is a function of TJ(max), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(max) - TA)/ RθJA. All numbers apply for packages soldered directly onto a PC board.
6.4 Thermal Information
THERMAL METRIC (1)
RθJA
(1)
(2)
4
Junction-to-ambient thermal resistance (2)
DGK
8 Pins
235
UNIT
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
The maximum power dissipation is a function of TJ(max), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(max) - TA)/ RθJA. All numbers apply for packages soldered directly onto a PC board.
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6.5 5V Electrical Characteristics
Unless otherwise specified, all limited ensured for V+ = 5V, V− = 0V, VCM = 0.5V, VO = V+/2, and RL > 1MΩ to V−. Boldface
limits apply at the temperature extremes.
PARAMETER
TEST CONDITIONS
VOS
Input Offset Voltage
VCM = 0.5V & VCM = 4.5V
TC VOS
Input Offset Average Drift
VCM = 0.5V & VCM = 4.5V (3)
IB
Input Bias Current
See
IOS
Input Offset Current
CMRR
Common Mode Rejection Ratio
VCM stepped from 0V to 5V
+PSRR
Positive Power Supply Rejection Ratio
V+ from 4.5V to 13V
CMVR
Input Common-Mode Voltage Range
CMRR > 50dB
TYP (1)
LIMIT (2)
UNIT
+/−0.7
+/−5
+/− 7
mV
max
+/−2
—
—
±2.00
±2.70
µA
max
20
250
400
nA
max
80
64
61
dB
min
100
78
74
dB
min
−0.3
−0.1
0.0
V
max
5.3
5.1
5.0
V
min
80
64
60
dB
min
V
min
(4)
AVOL
Large Signal Voltage Gain
VO = 0.5 to 4.5V,
RL = 10kΩ to V+/2
VO
Output Swing
High
RL = 10kΩ to V−
4.93
4.85
ISOURCE = 5mA
4.85
4.70
Output Swing
Low
RL = 10kΩ to V+
215
250
ISINK = 5mA
300
350
Output Short Circuit Current
Sourcing to V−
VID = 200mV (5)
100
—
Sinking to V+
VID = −200mV (5)
100
—
ISC
µV/°C
mV
max
mA
IOUT
Output Current
VID = ±200mV, VO = 1V from rails
±55
—
mA
IS
Supply Current (Both Channel)
No load, VCM = 0.5V
1.8
2.3
2.8
mA
max
SR
Slew Rate (6)
AV = +1, VI = 5VPP
12
—
V/µs
fu
Unity Gain Frequency
VI = 10mVp, RL = 2KΩ to V+/2
7.5
—
MHz
GBWP
Gain-Bandwidth Product
f = 50KHz
13
—
MHz
Phim
Phase Margin
VI = 10mVp, RL = 2kΩ to V+/2
55
—
deg
en
Input-Referred Voltage Noise
f = 2KHz, RS = 50Ω
15
—
nV/√Hz
in
Input-Referred Current Noise
f = 2KHz
1.4
—
pA/√Hz
fmax
Full Power Bandwidth
ZL = (20pF || 10kΩ) to V+/2
700
—
kHz
(1)
(2)
(3)
(4)
(5)
(6)
Typical Values represent the most likely parametric norm.
All limits are ensured by testing or statistical analysis.
Offset voltage average drift determined by dividing the change in VOS at temperature extremes into the total temperature change.
Positive current corresponds to current flowing into the device.
Short circuit test is a momentary test. Output short circuit duration is infinite for VS ≤ 6V at room temperature and below. For VS > 6V,
allowable short circuit duration is 1.5ms.
Slew rate is the slower of the rising and falling slew rates. Connected as a Voltage Follower.
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6.6 12V Electrical Characteristics
Unless otherwise specified, all limited ensured for V+ = 12V, V− = 0V, VCM = 6V, VO = 6V, and RL > 1MΩ to V−. Boldface
limits apply at the temperature extremes.
PARAMETER
TEST CONDITIONS
VOS
Input Offset Voltage
VCM = 0.5V & VCM = 11.5V
TC VOS
Input Offset Average Drift
VCM = 0.5V & VCM = 11.5V (3)
IB
Input Bias Current
See
IOS
Input Offset Current
CMRR
Common Mode Rejection Ratio
VCM stepped from 0V to 12V
+PSRR
Positive Power Supply Rejection Ratio
V+ from 4.5V to 13V, VCM = 0.5V
−PSRR
Negative Power Supply Rejection Ratio
CMVR
Input Common-Mode Voltage Range
TYP (1)
LIMIT (2)
UNIT
+/−0.7
+/−7
+/− 9
mV
max
+/−2
—
—
±2.00
±2.80
µA
max
30
275
550
nA
max
88
74
72
dB
min
100
78
74
dB
min
85
—
dB
−0.3
−0.1
0
V
max
12.3
12.1
12.0
V
min
83
74
70
dB
min
V
min
(4)
CMRR > 50dB
AVOL
Large Signal Voltage Gain
VO = 1V to 11V
RL = 10kΩ to V+/2
VO
Output Swing
High
RL 10kΩ to V+/2
11.8
11.7
ISOURCE = 5mA
11.6
11.5
Output Swing
Low
RL = 10kΩ to V+/2
0.25
0.3
.40
.45
Output Short Circuit Current
Sourcing to V−
VID = 200mV (5)
130
110
130
110
ISC
ISINK = 5mA
+
Sinking to V
VID = 200mV
(5)
µV/°C
V
max
mA
min
IOUT
Output Current
VID = ±200mV, VO = 1V from rails
±65
—
mA
IS
Supply Current (Both Channel)
No load, VCM = 0.5V
1.9
2.4
2.9
mA
max
SR
Slew Rate (6)
AV = +1, VI = 10VPP, CL = 10pF
15
—
AV = +1, VI = 10VPP, CL = 0.1µF
1
—
V/µs
ROUT
Close Loop Output Resistance
AV = +1, f = 100KHz
3
—
Ω
fu
Unity Gain Frequency
VI = 10mVp, RL = 2kΩ to V+/2
8
—
MHz
GBWP
Gain-Bandwidth Product
f = 50KHz
15
—
MHz
Phim
Phase Margin
VI = 10mVp, RL = 2kΩ to V+/2
57
—
Deg
GM
Gain Margin
VI = 10mVp, RL = 2kΩ to V+/2
20
—
dB
AV = +1, RL = 2kΩ to V /2
12.5
—
AV = +1, RL = 600Ω to V+/2
10.5
—
AV = +10, RL = 600Ω to V+/2
1.0
—
−3dB BW
(1)
(2)
(3)
(4)
(5)
(6)
6
Small Signal -3db Bandwidth
+
MHz
Typical Values represent the most likely parametric norm.
All limits are ensured by testing or statistical analysis.
Offset voltage average drift determined by dividing the change in VOS at temperature extremes into the total temperature change.
Positive current corresponds to current flowing into the device.
Short circuit test is a momentary test. Output short circuit duration is infinite for VS ≤ 6V at room temperature and below. For VS > 6V,
allowable short circuit duration is 1.5ms.
Slew rate is the slower of the rising and falling slew rates. Connected as a Voltage Follower.
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12V Electrical Characteristics (continued)
Unless otherwise specified, all limited ensured for V+ = 12V, V− = 0V, VCM = 6V, VO = 6V, and RL > 1MΩ to V−. Boldface
limits apply at the temperature extremes.
PARAMETER
TEST CONDITIONS
TYP (1)
LIMIT (2)
15
—
nV/√Hz
UNIT
en
Input-Referred Voltage Noise
f = 2KHz, RS = 50Ω
in
Input-Referred Current Noise
f = 2KHz
1.4
—
pA/√Hz
fmax
Full Power Bandwidth
ZL = (20pF || 10kΩ) to V+/2
300
—
kHz
THD+N
Total Harmonic Distortion +Noise
AV = +2, RL = 2kΩ to V+/2
VO = 8VPP, VS = ±5V
0.02%
—
CT Rej.
Cross-Talk Rejection
f = 5MHz, Driver RL = 10kΩ to V+/2
68
—
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6.7 Typical Performance Characteristics
Figure 1. VOS Distribution
Figure 2. VOS vs. VCM for 3 Representative Units
Figure 3. VOS vs. VCM for 3 Representative Units
Figure 4. VOS vs. VCM for 3 Representative Units
Figure 5. VOS vs. VS for 3 Representative Units
8
Figure 6. VOS vs. VS for 3 Representative Units
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Typical Performance Characteristics (continued)
Figure 7. VOS vs. VS for 3 Representative Units
Figure 8. IB vs. VS
Figure 9. IB vs. VS
Figure 10. IS vs. VCM
Figure 12. IS vs. VS
Figure 11. IS vs. VCM
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Typical Performance Characteristics (continued)
10
Figure 13. IS vs. VS
Figure 14. CMRR vs. Frequency
Figure 15. +PSRR vs. Frequency
Figure 16. −PSRR vs. Frequency
Figure 17. Open Loop Gain/Phase
for Various Supplies
Figure 18. Closed Loop Frequency Response
for Various Gains
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Typical Performance Characteristics (continued)
Figure 19. Closed Loop Frequency Response
for Various Gains
Figure 20. Closed Loop Frequency Response
for Various RL
Figure 21. Maximum Output Swing vs. Load
(1% Distortion)
Figure 22. Maximum Output Swing vs. Frequency
(1% Distortion)
Figure 23. Closed Loop Small Signal Frequency Response
for Various CL
Figure 24. Overshoot vs. Cap Load
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Typical Performance Characteristics (continued)
12
Figure 25. Settling Time (±1%) & Slew Rate vs. Cap Load
Figure 26. VOUT from V+ vs. ISOURCE
Figure 27. VOUT from V− vs. ISINK
Figure 28. Step Response for Various Amplitudes
Figure 29. Step Response for Various Amplitudes
Figure 30. Large Signal Step Response
for Various Cap Loads
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Typical Performance Characteristics (continued)
Figure 31. THD+N vs. Input Amplitude
for Various Frequency
Figure 32. Input Referred Noise Density
Figure 33. Closed Loop Output Impedance vs. Frequency
Figure 34. Crosstalk Rejection vs. Frequency
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7 Application and Implementation
7.1 Block Diagram and Operational Description
A) Input Stage:
As seen in Figure 35, the input stage consists of two distinct differential pairs (Q1-Q2 and Q3-Q4) in order to
accommodate the full Rail-to-Rail input common mode voltage range. The voltage drop across R5, R6, R7 and
R8 is kept to less than 200 mV in order to allow the input to exceed the supply rails. Q13 acts as a switch to
steer current away from Q3-Q4 and into Q1-Q2, as the input increases beyond 1.4 of V+. This in turn shifts the
signal path from the bottom stage differential pair to the top one and causes a subsequent increase in the supply
current.
In transitioning from one stage to another, certain input stage parameters (VOS, Ib, IOS, en, and in) are determined
based on which differential pair is “on” at the time. Input Bias current, Ib, will change in value and polarity as the
input crosses the transition region. In addition, parameter such as PSRR and CMRR which involve the input
offset voltage will also be effected by changes in VCM across the differential pair transition region.
Figure 35. Simplified Schematic Diagram
14
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Block Diagram and Operational Description
A) Input Stage: (continued)
The input stage is protected with the combination of R9-R10 and D1, D2, D3 and D4 against differential input
over-voltages. This fault condition could otherwise harm the differential pairs or cause offset voltage shift in case
of prolonged over voltage. As shown in Figure 36, if this voltage reaches approximately ±1.4V at 25°C, the
diodes turn on and current flow is limited by the internal series resistors (R9 and R10). The Absolute Maximum
Rating of ±10V differential on VIN still needs to be observed. With temperature variation, the point were the
diodes turn on will change at the rate of 5mV/°C
Figure 36. Input Stage Current vs. Differential Input Voltage
7.2 B) Output Stage:
The output stage (see Figure 35) is comprised of complimentary NPN and PNP common-emitter stages to permit
voltage swing to within a Vce(sat) of either supply rail. Q9 supplies the sourcing and Q10 supplies the sinking
current load. Output current limiting is achieved by limiting the Vce of Q9 and Q10. Using this approach to current
limiting alleviates the drawback to the conventional scheme which requires one Vbe reduction in output swing.
The frequency compensation circuit includes Miller capacitors from collector to base of each output transistor
(see Figure 35, Ccomp9 and Ccomp10). At light capacitive loads, the high frequency gain of the output transistors is
high, and the Miller effect increases the effective value of the capacitors thereby stabilizing the Op Amp. Large
capacitive loads greatly decrease the high frequency gain of the output transistors thus lowering the effective
internal Miller capacitance - the internal pole frequency increases at the same time a low frequency pole is
created at the Op Amp output due to the large load capacitor. In this fashion, the internal dominant pole
compensation, which works by reducing the loop gain to less than 0dB when the phase shift around the feedback
loop is more than 180°, varies with the amount of capacitive load and becomes less dominant when the load
capacitor has increased enough. Hence the Op Amp is very stable even at high values of load capacitance
resulting in the uncharacteristic feature of stability under all capacitive loads.
7.3 C) Output Voltage Swing Close to V−:
The LM8272's output stage design allows voltage swings to within millivolts of either supply rail for maximum
flexibility and improved useful range. Because of this design architecture, as can be seen from Figure 35
diagram, with Output approaching either supply rail, either Q9 or Q10 Collector-Base junction reverse bias will
decrease. With output less than a Vbe from either rail, the corresponding output transistor operates near
saturation. In this mode of operation, the transistor will exhibit higher junction capacitance and lower ft which will
reduce Phase Margin. With the Noise Gain (NG = 1 + Rf/Rg, Rf & Rg are external gain setting resistors) of 2 or
higher, there is sufficient Phase Margin that this reduction (in Phase Margin) is of no consequence. However,
with lower Noise Gain (<2) and with less than 150mV voltage to the supply rail, if the output loading is light, the
Phase Margin reduction could result in unwanted oscillations.
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C) Output Voltage Swing Close to V−: (continued)
In the case of the LM8272, due to inherent architectural specifics, the oscillation occurs only with respect to Q10
when output swings to within 150mV of V−. However, if Q10 collector current is larger than its idle value of a few
microamps, the Phase Margin loss becomes insignificant. In this case, 300µA is the required Q10 collector
current to remedy this situation. Therefore, when all the aforementioned critical conditions are present at the
same time (NG < 2, VOUT < 150mV from supply rails, & output load is light) it is possible to ensure stability by
adding a load resistor to the output to provide the necessary Q10 minimum Collector Current (300µA).
For 12V (or ±6V) operation, for example, add a 39kΩ resistor from the output to V+ to cause 300µA output
sinking current and ensure stability. This is equivalent to about 15% increase in total quiescent power dissipation.
7.4 Driving Capactive Loads:
The LM8272 is specifically designed to drive unlimited capacitive loads without oscillations (see Figure 25). In
addition, the output current handling capability of the device allows for good slewing characteristics even with
large capacitive loads (Settling Time and Slew Rate vs. Cap Load plot). The combination of these features is
ideal for applications such as TFT flat panel buffers, A/D converter input amplifiers, etc.
However, as in most Op Amps, addition of a series isolation resistor between the Op Amp and the capacitive
load improves the settling and overshoot performance.
Output current drive is an important parameter when driving capacitive loads. This parameter will determine how
fast the output voltage can change. Referring to Figure 25, two distinct regions can be identified. Below about
10,000pF, the output Slew Rate is solely determined by the Op Amp's compensation capacitor value and
available current into that capacitor. Beyond 10nF, the Slew Rate is determined by the Op Amp's available output
current. An estimate of positive and negative slew rates for loads larger than 100nF can be made by dividing the
short circuit current value by the capacitor.
7.5 Estimating the Output Voltage Swing
It is important to keep in mind that the steady state output current will be less than the current available when
there is an input overdrive present. For steady state conditions, Figure 37 and Figure 38 plots can be used to
predict the output swing. These plots also show several load lines corresponding to loads tied between the
output and ground. In each case, the intersection of the device plot at the appropriate temperature with the load
line would be the typical output swing possible for that load. For example, a 600-Ω load can accommodate an
output swing to within 100mV of V− and to 250mV of V+ (VS = ±5V) corresponding to a typical 9.65VPP unclipped
swing.
Figure 37. Steady State Output Sourcing Characteristics with Load Lines
16
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Estimating the Output Voltage Swing (continued)
Figure 38. Steady State Output Sinking Characteristics with Load Lines
7.6 Output Short Circuit Current and Dissipation Issues:
The LM8272 output stage is designed for maximum output current capability. Even though momentary output
shorts to ground and either supply can be tolerated at all operating voltages, longer lasting short conditions can
cause the junction temperature to rise beyond the absolute maximum rating of the device, especially at higher
supply voltage conditions. Below supply voltage of 6V, output short circuit condition can be tolerated indefinitely.
With the Op Amp tied to a load, the device power dissipation consists of the quiescent power due to the supply
current flow into the device, in addition to power dissipation due to the load current. The load portion of the
power itself could include an average value (due to a DC load current) and an AC component. DC load current
would flow if there is an output voltage offset, or if the output AC average current is non-zero, or if the Op Amp
operates in a single supply application where the output is maintained somewhere in the range of linear
operation. Therefore:
Ptotal = PQ + PDC + PAC
PQ = IS · VS (Op Amp Quiescent Power Dissipation)
PDC = IO · (Vr - Vo) (DC Load Power)
PAC = See Table 1 below
(1)
(2)
(3)
(AC Load Power)
where:
• IS: Supply Current
• VS: Total Supply Voltage (V+ - V−)
• VO: Average Output Voltage
• Vr: V+ for sourcing and V− for sinking current
Table 1 below shows the maximum AC component of the load power dissipated by the Op Amp for standard
Sinusoidal, Triangular, and Square Waveforms:
Table 1. Normalized AC Power Dissipated in the Output Stage for Standard Waveforms
PAC (W.Ω/V2)
SINUSOIDAL
TRIANGULAR
SQUARE
50.7 × 10−3
46.9 × 10−3
62.5 × 10−3
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The table entries are normalized to VS2/RL. To figure out the AC load current component of power dissipation,
simply multiply the table entry corresponding to the output waveform by the factor VS2/RL. For example, with
±12V supplies, a 600Ω load, and triangular waveform power dissipation in the output stage is calculated as:
PAC = (46.9 × 10−3) · [242/600] = 45.0mW
(4)
7.7 Other Application Hints:
The use of supply decoupling is mandatory in most applications. As with most relatively high speed/high output
current Op Amps, best results are achieved when each supply line is decoupled with two capacitors; a small
value ceramic capacitor (∼0.01µF) placed very close to the supply lead in addition to a large value Tantalum or
Aluminum (> 4.7µF). The large capacitor can be shared by more than one device if necessary. The small
ceramic capacitor maintains low supply impedance at high frequencies while the large capacitor will act as the
charge “bucket” for fast load current spikes at the Op Amp output. The combination of these capacitors will
provide supply decoupling and will help keep the Op Amp oscillation free under any load.
7.8 LM8272 Advantages:
Compared to other Rail-to-Rail Input/Output devices, the LM8272 offers several advantages such as:
• Improved cross over distortion
• Nearly constant supply current throughout the output voltage swing range and close to either rail.
• Nearly constant Unity gain frequency (fu) and Phase Margin (Phim) for all operating supplies and load
conditions.
• No output phase reversal under input overload condition.
18
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8 Device and Documentation Support
8.1 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
8.2 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
8.3 Electrostatic Discharge Caution
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.
8.4 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
9 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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19
PACKAGE OPTION ADDENDUM
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29-Jul-2015
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)
LM8272MM
NRND
VSSOP
DGK
8
1000
TBD
Call TI
Call TI
-40 to 85
A60
LM8272MM/NOPB
ACTIVE
VSSOP
DGK
8
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
A60
LM8272MMX/NOPB
ACTIVE
VSSOP
DGK
8
3500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
A60
(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.
(4)
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
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
29-Jul-2015
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
29-Sep-2019
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM8272MM
VSSOP
DGK
8
1000
178.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
LM8272MM/NOPB
VSSOP
DGK
8
1000
178.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
LM8272MMX/NOPB
VSSOP
DGK
8
3500
330.0
12.4
5.3
3.4
1.4
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
29-Sep-2019
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM8272MM
VSSOP
DGK
8
1000
210.0
185.0
35.0
LM8272MM/NOPB
VSSOP
DGK
8
1000
210.0
185.0
35.0
LM8272MMX/NOPB
VSSOP
DGK
8
3500
367.0
367.0
35.0
Pack Materials-Page 2
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IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD
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