LM4911 [NSC]
Stereo 40mW Low Noise Headphone Amplifier with Selectable Capacitive Coupled or OCL Output; 立体声40mW的低噪声耳机放大器，具有可选的电容耦合或OCL输出
| 型号： | LM4911 |
| 厂家： | 
National Semiconductor |
| 描述： | Stereo 40mW Low Noise Headphone Amplifier with Selectable Capacitive Coupled or OCL Output |
| 文件： | 总18页 (文件大小：925K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
July 2002
LM4911
Stereo 40mW Low Noise Headphone Amplifier with
Selectable Capacitive Coupled or OCL Output
General Description
Key Specifications
n PSRR at 217 Hz and 1kHz
65dB (typ)
The LM4911 is an stereo audio power amplifier capable of
delivering 40mW per channel of continuous average power
into a 16Ω load or 25mW per channel into a 32Ω load at 1%
THD+N from a 3V power supply.
n Output Power at 1kHz with VDD = 2.4V, 1% THD+N into
a 16Ω load 25mW (typ)
n Output Power at 1kHz with VDD = 3V, 1% THD+N into a
16Ω load
n Shutdown Current
n Output Voltage change on release from Shutdown
VDD = 2.4V, RL = 16Ω (C-Coupled) 1mV (max)
n Mute Current 100µA (max)
40mW (typ)
2.0µA (max)
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. Since the LM4911 does not require
bootstrap capacitors or snubber networks, it is optimally
suited for low-power portable systems. In addition, the
LM4911 may be configured for either single-ended capaci-
tively coupled outputs or for OCL outputs (patent pending).
Features
The LM4911 features a low-power consumption shutdown
mode and a power mute mode that allows for faster turn on
time with less than 1mV voltage change at outputs on re-
lease. Additionally, the LM4911 features an internal thermal
shutdown protection mechanism.
n OCL or capacitively coupled outputs (patent pending)
n External gain-setting capability
n Available in space-saving MSOP package
n Ultra low current shutdown mode
n Mute mode allows fast turn-on (1ms) with less than 1mV
change on outputs
The LM4911 is unity gain stable and may be configured with
external gain-setting resistors.
n 2V - 5.5V operation
n Ultra low noise
Applications
n Portable CD players
n PDAs
n Portable electronics devices
Block Diagram
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FIGURE 1. Block Diagram
Boomer® is a registered trademark of National Semiconductor Corporation.
© 2002 National Semiconductor Corporation
DS200314
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Typical Application
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FIGURE 2. Typical Capacitive Coupled Output Configuration Circuit
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FIGURE 3. Typical OCL Output Configuration Circuit
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2
Connection Diagrams
MSOP Package
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Top View
Order Number LM4911MM
See NS Package Number MUB10A
MSOP Marking
200314A9
Top View
G-Boomer Family
A3 - LM4911MM
3
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Absolute Maximum Ratings (Note 2)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Thermal Resistance
θJC (MSOP)
56˚C/W
θJA (MSOP)
190˚C/W
Supply Voltage
6.0V
−65˚C to +150˚C
-0.3V to VDD + 0.3V
Internally Limited
2000V
Operating Ratings
Temperature Range
Storage Temperature
Input Voltage
TMIN ≤ TA ≤ TMAX
−40˚C ≤ T ≤ 85˚C
A
Power Dissipation (Note 3)
ESD Susceptibility (Note 4)
ESD Susceptibility (Note 5)
Junction Temperature
Supply Voltage (VDD
)
2V ≤ VCC ≤ 5.5V
200V
150˚C
Electrical Characteristics VDD = 5V (Notes 1, 2)
The following specifications apply for VDD = 5V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA
25˚C.
=
Symbol
Parameter
Conditions
LM4911
Units
(Limits)
Typ
(Note 6)
2
Limit
(Note 7)
5
IDD
ISD
IM
Quiescent Power Supply Current VIN = 0V, IO = 0A
mA (max)
Shutdown Current
VSHUTDOWN = GND
0.1
µA(max)
Mute Current
VMUTE = VDD, C-Coupled
100
1.8
µA(max)
VSDIH
VSDIL
VMIH
VMIL
PO
Shutdown Voltage Input High
Shutdown Voltage Input Low
Mute Voltage Input High
Mute Voltage Input Low
Output Power
V
V
V
V
0.4
1.8
0.4
THD ≤ 1%; f=1 kHZ
OCL, RL= 16Ω
80
80
OCL, RL= 32Ω
mW
C-CUPL, RL= 16Ω
145
85
C-CUPL, RL= 32Ω
VON
Output Noise Voltage
BW = 20Hz to 20kHz, A-weighted
VRIPPLE = 200mV sine p-p
f = 1kHz (Note 9)
10
µV
dB
PSRR
Power Supply Rejection Ratio
65
Electrical Characteristics VDD = 3.0V (Notes 1, 2)
The following specifications apply for VDD = 3.0V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA
=
25˚C.
Symbol
Parameter
Conditions
LM4911
Units
(Limits)
Typ
(Note 6)
1.5
Limit
(Note 7)
3
IDD
ISD
IM
Quiescent Power Supply Current VIN = 0V, IO = 0A
mA (max)
µA(max)
µA(max)
Shutdown Current
Mute Current
VSHUTDOWN = GND
VMUTE = VDD, C-Coupled
THD = 1%; f = 1kHz
R = 16Ω
0.1
2.0
50
100
PO
Output Power
40
25
10
65
mW
R = 32Ω
VNO
Output Noise Voltage
BW = 20 Hz to 20kHz, A-weighted
VRIPPLE = 200mV sine p-p
µV
dB
PSRR
Power Supply Rejection Ratio
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4
Electrical Characteristics VDD = 2.4V (Notes 1, 2)
The following specifications apply for VDD = 2.4V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA
=
25˚C.
Symbol
Parameter
Conditions
LM4911
Units
(Limits)
Typ
(Note 6)
1.5
Limit
(Note 7)
3
IDD
ISD
IM
Quiescent Power Supply Current VIN = 0V, IO = 0A
mA (max)
µA(max)
µA(max)
Shutdown Current
Mute Current
VSHUTDOWN = GND
VMUTE = VDD, C-Coupled
THD = 1%; f = 1kHz
R = 16Ω
0.1
2.0
40
80
PO
Output Power
25
12
10
65
0.5
2
mW
R = 32Ω
VNO
Output Noise Voltage
BW = 20 Hz to 20kHz, A-weighted
VRIPPLE = 200mV sine p-p
OCL
µV
dB
PSRR
TWU
Power Supply Rejection Ratio
Wake Up Time from Shutdown
s
C-Coupled, CO = 100µF
VOSD
TUM
Output Voltage Change on
Release from Shutdown
Time to Un-Mute
C-Coupled, CO = 100µF
C-Coupled, CO = 100µF
1
mV (max)
s (max)
0.01
0.02
Note 1: All voltages are measured with respect to the GND pin unless otherwise specified.
Note 2: : Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional but do not guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which
guarantee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where no limit
is given, however, the typical value is a good indication of device performance.
Note 3: : The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, θ , and the ambient temperature, T . The
JA
A
maximum allowable power dissipation is P
= (T
- T )/ θ or the number given in Absolute Maximum Ratings, whichever is lower. For the LM4911, see
JMAX A JA
DMAX
power derating currents for more information.
Note 4: Human body model, 100pF discharged through a 1.5kΩ resistor.
Note 5: Machine Model, 220pF-240pF discharged through all pins.
Note 6: Typicals are measured at 25˚C and represent the parametric norm.
Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 8: Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Note 9: 10Ω Terminated input.
External Components Description (Figure 2)
Components
Functional Description
1.
2.
RI
CI
Inverting input resistance which sets the closed-loop gain in conjunction with Rf. This resistor also forms a
high-pass filter with Ci at fc = 1/(2πRiCi).
Input coupling capacitor which blocks the DC voltage at the amplifier’s input terminals. Also creates a
high-pass filter with Ri at fc = 1/(2πRiCi). Refer to the section Proper Selection of External Components, for
an explanation of how to determine the value of Ci.
3.
4.
Rf
Feedback resistance which sets the closed-loop gain in conjunction with Ri.
Supply bypass capacitor which provides power supply filtering. Refer to the Power Supply Bypassing
section for information concerning proper placement and selection of the supply bypass capacitor.
Bypass pin capacitor which provides half-supply filtering. Refer to the section, Proper Selection of Proper
Components, for information concerning proper placement and selection of CB
Output coupling capacitor which blocks the DC voltage at the amplifier’s output. Forms a high pass filter with
RL at fo = 1/(2πRLCo)
CS
5.
6.
CB
Co
5
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Typical Performance Characteristics
THD+N vs Frequency
THD+N vs Frequency
THD+N vs Frequency
THD+N vs Frequency
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20031483
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THD+N vs Frequency
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THD+N vs Frequency
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Typical Performance Characteristics (Continued)
THD+N vs Frequency
THD+N vs Frequency
THD+N vs Frequency
THD+N vs Frequency
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20031404
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THD+N vs Frequency
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THD+N vs Frequency
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7
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Typical Performance Characteristics (Continued)
THD+N vs Output Power
THD+N vs Output Power
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20031491
THD+N vs Output Power
THD+N vs Output Power
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THD+N vs Output Power
THD+N vs Output Power
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20031407
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Typical Performance Characteristics (Continued)
THD+N vs Output Power
THD+N vs Output Power
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20031409
Output Resistance vs Load Resistance
Output Power vs Supply Voltage
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20031412
Output Power vs Supply Voltage
Output Power vs Supply Voltage
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20031495
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Typical Performance Characteristics (Continued)
Output Power vs Supply Voltage
Output Power vs Load Resistance
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Output Power vs Load Resistance
Power Dissipation vs. Output Power
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20031498
Power Dissipation vs. Output Power
Power Dissipation vs Output Power
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200314A0
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Typical Performance Characteristics (Continued)
Channel Seperation
Channel Seperation
Channel Seperation
Channel Seperation
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200314A2
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Channel Seperation
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Channel Seperation
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Typical Performance Characteristics (Continued)
Power Supply Rejection Ratio
Power Supply Rejection Ratio
Power Supply Rejection Ratio
Power Supply Rejection Ratio
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200314A4
200314A6
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Power Supply Rejection Ratio
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Power Supply Rejection Ratio
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Typical Performance Characteristics (Continued)
Power Supply Rejection Ratio
Power Supply Rejection Ratio
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20031422
Frequency Response vs
Input Capacitor Size
Frequency Response vs
Input Capacitor Size
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20031426
Supply Voltage vs
Supply Current
Open Loop Frequency Response
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200314A7
13
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Typical Performance Characteristics (Continued)
Clipping Voltage vs
Supply Voltage
Noise Floor
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200314A8
Shutdown Hysteresis Voltage, Vdd=5V
Shutdown Hysteresis Voltage, Vdd=3V
200314B1
200314B2
Power Derating Curve
200314B3
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POWER DISSIPATION
Application Information
Power dissipation is a major concern when using any power
amplifier and must be thoroughly understood to ensure a
successful design. When operating in capacitor-coupled
mode, Equation 1 states the maximum power dissipation
point for a single-ended amplifier operating at a given supply
voltage and driving a specified output load.
AMPLIFIER CONFIGURATION EXPLANATION
As shown in Figure 1, the LM4911 has three operational
amplifiers internally. Two of the amplifier’s have externally
configurable gain while the other amplifier is internally fixed
at the bias point acting as a unity-gain buffer. The closed-
loop gain of the two configurable amplifiers is set by select-
ing the ratio of Rf to Ri. Consequently, the gain for each
channel of the IC is
2
PDMAX = (VDD
)
/ (2π2RL)
(1)
Since the LM4911 has two operational amplifiers in one
package, the maximum internal power dissipation point is
twice that of the number which results from Equation 1. From
Equation 1, assuming a 3V power supply and an 32Ω load,
the maximum power dissipation point is 14mW per amplifier.
Thus the maximum package dissipation point is 28mW.
AVD = -(Rf / Ri)
By driving the loads through outputs VoA and VoB with VoC
acting as a buffered bias voltage the LM4911 does not
require output coupling capacitors. The classical single-
ended amplifier configuration where one side of the load is
connected to ground requires large, expensive output cou-
pling capacitors.
When operating in OCL mode, the maximum power dissipa-
tion increases due to the use of the third amplifier as a buffer
and is given in Equation 2:
A configuration, such as the one used in the LM4911, has a
major advantage over single supply, single-ended amplifiers.
Since the outputs VoA, VoB, and VoC are all biased at 1/2
VDD, no net DC voltage exists across each load. This elimi-
nates the need for output coupling capacitors which are
required in a single-supply, single-ended amplifier configura-
tion. Without output coupling capacitors in a typical single-
supply, single-ended amplifier, the bias voltage is placed
across the load resulting in both increased internal IC power
dissipation and possible loudspeaker damage.
2
PDMAX = 4(VDD
)
/ (π2RL)
(2)
The maximum power dissipation point obtained from either
Equation 1 or 2 must not be greater than the power dissipa-
tion that results from Equation 3:
PDMAX = (TJMAX - TA) / θJA
(3)
OUTPUT CAPACITOR vs. CAPACITOR COUPLED
For package MUB10A, θJA = 190˚C/W. TJMAX = 150˚C for
the LM4911. Depending on the ambient temperature, TA, of
the system surroundings, Equation 3 can be used to find the
maximum internal power dissipation supported by the IC
packaging. If the result of Equation 1 or 2 is greater than that
of Equation 3, then either the supply voltage must be de-
creased, the load impedance increased or TA reduced. For
the typical application of a 3V power supply, with an 32Ω
load, the maximum ambient temperature possible without
violating the maximum junction temperature is approximately
144˚C provided that device operation is around the maxi-
mum power dissipation point. Thus, for typical applications,
power dissipation is not an issue. Power dissipation is a
function of output power and thus, if typical operation is not
around the maximum power dissipation point, the ambient
temperature may be increased accordingly. Refer to the
Typical Performance Characteristics curves for power dissi-
pation information for lower output powers.
The LM4911 is a stereo audio power amplifier capable of
operating in two distinct output modes: capacitor coupled
(C-CUPL) or output capacitor-less (OCL). The LM4911 may
be run in capacitor coupled mode by using a coupling ca-
pacitor on each single-ended output (VoA and VoB) and
connecting VoC to ground. This output coupling capacitor
blocks the half supply voltage to which the output amplifiers
are typically biased and couples the audio signal to the
headphones or other single-ended (SE) load. The signal
return to circuit ground is through the headphone jack’s
sleeve.
The LM4911 can also eliminate these output coupling ca-
pacitors by running in OCL mode. Unless shorted to ground,
VoC is internally configured to apply a 1⁄
Vdd bias voltage to
2
a stereo headphone jack’s sleeve. This voltage matches the
bias voltage present on VoA and VoB outputs that drive the
headphones. The headphones operate in a manner similar
to a bridge-tied load (BTL). Because the same DC voltage is
applied to both headphone speaker terminals this results in
no net DC current flow through the speaker. AC current flows
through a headphone speaker as an audio signal’s output
amplitude increases on the speaker’s terminal.
POWER SUPPLY BYPASSING
As with any amplifier, proper supply bypassing is important
for low noise performance and high power supply rejection.
The capacitor location on the power supply pins should be
as close to the device as possible.
The headphone jack’s sleeve is not connected to circuit
ground when used in OCL mode. Using the headphone
output jack as a line-level output will place the LM4911’s ⁄
Typical applications employ a 3V regulator with 10mF tanta-
lum or electrolytic capacitor and a ceramic bypass capacitor
which aid in supply stability. This does not eliminate the need
for bypassing the supply nodes of the LM4911. A bypass
capacitor value in the range of 0.1µF to 1µF is recommended
for CS.
1
2
Vdd bias voltage on a plug’s sleeve connection. This pre-
sents no difficulty when the external equipment uses capaci-
tively coupled inputs. For the very small minority of equip-
ment that is DC coupled, the LM4911 monitors the current
supplied by the amplifier that drives the headphone jack’s
sleeve. If this current exceeds 500mAPK, the amplifier is
shutdown, protecting the LM4911 and the external equip-
ment.
15
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Additionally, Mute should not be enabled during shutdown or
while entering or returning from shutdown. This is not a valid
operation condition and may result in much higher pop and
click values.
Application Information (Continued)
MICRO POWER SHUTDOWN
The voltage applied to the SHUTDOWN pin controls the
LM4911’s shutdown function. Activate micro-power shut-
down by applying a logic-low voltage to the SHUTDOWN
pin. When active, the LM4911’s micro-power shutdown fea-
ture turns off the amplifier’s bias circuitry, reducing the sup-
ply current. The trigger point varies depending on supply
voltage and is shown in the Shutdown Hysteresis Voltage
graphs in the Typical Performance Characteristics section.
The low 0.1µA(typ) shutdown current is achieved by apply-
ing a voltage that is as near as ground as possible to the
SHUTDOWN pin. A voltage that is higher than ground may
increase the shutdown current. There are a few ways to
control the micro-power shutdown. These include using a
single-pole, single-throw switch, a microprocessor, or a mi-
crocontroller. When using a switch, connect an external
100kΩ pull-up resistor between the SHUTDOWN pin and
VDD. Connect the switch between the SHUTDOWN pin and
ground. Select normal amplifier operation by opening the
switch. Closing the switch connects the SHUTDOWN pin to
ground, activating micro-power shutdown.
PROPER SELECTION OF EXTERNAL COMPONENTS
Proper selection of external components in applications us-
ing integrated power amplifiers is critical to optimize device
and system performance. While the LM4911 is tolerant of
external component combinations, consideration to compo-
nent values must be used to maximize overall system qual-
ity.
The LM4911 is unity-gain stable which gives the designer
maximum system flexibility. The LM4911 should be used in
low gain configurations to minimize THD+N values, and
maximize the signal to noise ratio. Low gain configurations
require large input signals to obtain a given output power.
Input signals equal to or greater than 1Vrms are available
from sources such as audio codecs. Very large values
should not be used for the gain-setting resistors. Values for
Ri and Rf should be less than 1MΩ. Please refer to the
section, Audio Power Amplifier Design, for a more com-
plete explanation of proper gain selection
The switch and resistor guarantee that the SHUTDOWN pin
will not float. This prevents unwanted state changes. In a
system with a microprocessor or microcontroller, use a digi-
tal output to apply the control voltage to the SHUTDOWN
pin. Driving the SHUTDOWN pin with active circuitry elimi-
nates the pull-up resistor.
Besides gain, one of the major considerations is the closed-
loop bandwidth of the amplifier. To a large extent, the band-
width is dictated by the choice of external components
shown in Figures 2 and 3. The input coupling capacitor, Ci,
forms a first order high pass filter which limits low frequency
response. This value should be chosen based on needed
frequency response and turn-on time.
Shutdown enable/disable times are controlled by a combina-
tion of CB and VDD. Larger values of CB results in longer turn
on/off times from Shutdown. Smaller Vdd values also in-
crease turn on/off time for a given value of CB. Longer
shutdown times also improve the LM4911’s resistance to
click and pop upon entering or returning from shutdown. For
a 2.4V supply and CB = 4.7µF, the LM4911 requires about 2
seconds to enter or return from shutdown. This longer shut-
down time enables the LM4911 to have virtually zero pop
and click transients upon entering or release from shutdown.
SELECTION OF INPUT CAPACITOR SIZE
Amplifying the lowest audio frequencies requires a high
value input coupling capacitor, Ci. A high value capacitor can
be expensive and may compromise space efficiency in por-
table designs. In many cases, however, the headphones
used in portable systems have little ability to reproduce
signals below 60Hz. Applications using headphones with this
limited frequency response reap little improvement by using
a high value input capacitor.
Smaller values of CB will decrease turn-on time, but at the
cost of increased pop and click and reduced PSRR. Since
shutdown enable/disable times increase dramatically as
supply voltage gets below 2.2V, this reduced turn-on time
may be desirable if extreme low supply voltage levels are
used as this would offset increases in turn-on time caused by
the lower supply voltage. This technique is not recom-
mended for OCL mode since shutdown enable/disable times
are very fast (0.5s) independent of supply voltage.
In addition to system cost and size, turn on time is affected
by the size of the input coupling capacitor Ci. A larger input
coupling capacitor requires more charge to reach its quies-
cent DC voltage. This charge comes from the output via the
feedback Thus, by minimizing the capacitor size based on
necessary low frequency response, turn-on time can be
minimized. A small value of Ci (in the range of 0.1µF to
0.39µF), is recommended.
MUTE
AUDIO POWER AMPLIFIER DESIGN
When in C-CUPL mode, the LM4911 also features a mute
function that enables extremely fast turn-on/turn-off with a
minimum of output pop and click with a low current con-
sumption (≤ 100µA). The mute function leaves the outputs at
their bias level, thus resulting in higher power consumption
than shutdown mode, but also provides much faster turn
on/off times. Mute mode is enabled by providing a logic high
signal on the MUTE pin in the opposite manner as the
shutdown function described above. Threshold voltages and
activation techniques match those given for the shutdown
function as well.
A 25mW/32Ω Audio Amplifier
Given:
Power Output
Load Impedance
Input Level
25mWrms
32Ω
1Vrms
Input Impedance
20kΩ
A designer must first determine the minimum supply rail to
obtain the specified output power. By extrapolating from the
Output Power vs Supply Voltage graphs in the Typical Per-
formance Characteristics section, the supply rail can be
easily found.
The mute function is not necessary when the LM4911 is
operating in OCL mode since the shutdown function oper-
ates quickly in OCL mode with less power consumption than
mute.
3V is a standard voltage in most applications, it is chosen for
the supply rail. Extra supply voltage creates headroom that
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16
Ci ≥ 1 / (2π * 20kΩ * 20Hz) = 0.397µF; use 0.39µF.
Application Information (Continued)
The high frequency pole is determined by the product of the
desired frequency pole, fH, and the differential gain, AV. With
an AV = 1 and fH = 100kHz, the resulting GBWP = 100kHz
which is much smaller than the LM4911 GBWP of 10MHz.
This figure displays that is a designer has a need to design
an amplifier with higher differential gain, the LM4911 can still
be used without running into bandwidth limitations.
allows the LM4911 to reproduce peak in excess of 25mW
without producing audible distortion. At this time, the de-
signer must make sure that the power supply choice along
with the output impedance does not violate the conditions
explained in the Power Dissipation section.
Once the power dissipation equations have been addressed,
the required gain can be determined from Equation 2.
Figure 4 shows an optional resistor connected between the
amplifier output that drives the headphone jack sleeve and
ground. This resistor provides a ground path that supressed
power supply hum. Thishum may occur in applications such
as notebook computers in a shutdown condition and con-
nected to an external powered speaker. The resistor’s 100Ω
value is a suggested starting point. Its final value must be
determined based on the tradeoff between the amount of
noise suppression that may be needed and minimizing the
additional current drawn by the resistor (25mA for a 100Ω
resistor and a 5V supply).
(4)
From Equation 4, the minimum AV is 0.89; use AV = 1. Since
the desired input impedance is 20kΩ, and with a AV gain of
1, a ratio of 1:1 results from Equation 1 for Rf to Ri. The
values are chosen with Ri = 20kΩ and Rf = 20kΩ. The final
design step is to address the bandwidth requirements which
must be stated as a pair of -3dB frequency points. Five times
away from a -3dB point is 0.17dB down from passband
response which is better than the required 0.25dB speci-
fied.
ESD PROTECTION
As stated in the Absolute Maximum Ratings, the LM4911 has
a maximum ESD susceptibility rating of 2000V. For higher
ESD voltages, the addition of a PCDN042 dual transil (from
California Micro Devices), as shown in Figure 4, will provide
additional protection.
fL = 100Hz/5 = 20Hz
fH = 20kHz * 5 = 100kHz
As stated in the External Components section, Ri in con-
junction with Ci creates a
200314B4
Figure 4. The PCDN042 provides additional ESD protection beyond the 2000V shown in the
Absolute Maximum Ratings for the VOC output
17
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Physical Dimensions inches (millimeters) unless otherwise noted
MSOP
Order Number LM4911MM
NS Package Number MUB10A
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DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
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accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
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can be reasonably expected to cause the failure of
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National Semiconductor
Europe
National Semiconductor
Asia Pacific Customer
Response Group
Tel: 65-2544466
Fax: 65-2504466
National Semiconductor
Japan Ltd.
Tel: 81-3-5639-7560
Fax: 81-3-5639-7507
Fax: +49 (0) 180-530 85 86
Email: support@nsc.com
Email: europe.support@nsc.com
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
Email: ap.support@nsc.com
www.national.com
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.
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