NSC LM4926

LM4926
Ground-Referenced, Ultra Low Noise, Fixed Gain, 80mW
Stereo Headphone Amplifier
General Description
Key Specifications
The LM4926 is a ground referenced, fixed-gain audio power
amplifier capable of delivering 80mW of continuous average
power into a 16Ω single-ended load with less than 1%
THD+N from a 3V power supply.
The LM4926 features a new circuit technology that utilizes a
charge pump to generate a negative reference voltage. This
allows the outputs to be biased about ground, thereby eliminating output-coupling capacitors typically used with normal
single-ended loads.
The LM4926 features an Automatic Standby Mode circuitry
(patent pending). In the absence of an input signal, after
approximately 12 seconds, the LM4926 goes into low current standby mode. The LM4926 recovers into full power
operating mode immediately after a signal is applied to either
the left or right input pins. This feature saves power supply
current in battery operated applications.
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. The LM4926 does not require output
coupling capacitors or bootstrap capacitors, and therefore is
ideally suited for mobile phone and other low voltage applications where minimal power consumption is a primary requirement.
The LM4926 features a low-power consumption shutdown
mode selectable for either channel separately. This is accomplished by driving either the SD_RC (Shutdown Right
Channel) or SD_LC (Shutdown Left Channel) (or both) pins
with logic low, depending on which channel is desired shutdown. Additionally, the LM4926 features an internal thermal
shutdown protection mechanism.
The LM4926 contains advanced pop & click circuitry that
eliminates noises which would otherwise occur during
turn-on and turn-off transitions.
The LM4926 has an internal fixed gain of 1.5V/V.
j Improved PSRR at 217Hz
70dB (typ)
j Power Output at VDD = 3V,
RL = 16Ω, THD % 1%
80mW (typ)
j Shutdown Current
0.01µA (typ)
j Internal Fixed Gain
1.5V/V (typ)
j Operating Voltage
1.6V to 4.2V
Features
Ground referenced outputs
High PSRR
Available in space-saving micro SMD package
Ultra low current shutdown mode
Improved pop & click circuitry eliminates noises during
turn-on and turn-off transitions
n No output coupling capacitors, snubber networks,
bootstrap capacitors, or gain-setting resistors required
n Shutdown either channel independently
n
n
n
n
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Applications
n
n
n
n
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Notebook PCs
Mobile Phone
PDAs
Portable electronic devices
MP3 Players
Boomer ® is a registered trademark of National Semiconductor Corporation.
© 2005 National Semiconductor Corporation
DS201161
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LM4926 Ground-Referenced, Ultra Low Noise, Fixed Gain, 80mW Stereo Headphone Amplifier
June 2005
LM4926
Typical Application
201161B8
FIGURE 1. Typical Audio Amplifier Application Circuit
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LM4926
Connection Diagrams
microSMD Package
16 – Bump TL Marking
20116178
Top View
XY – Date Code
TT – Lot Traceability
G – Boomer Family
E8 – LM4926TL
20116109
Top View
Order Number LM4926TL
See NS Package Number TLE1411A
Pin Descriptions
Pin
Name
Function
A1
R_IN
Right Channel Input
A2
SGND
Signal Ground
A3
CPVDD
Charge Pump Power Supply
A4
CCP+
Positive Terminal - Charge Pump Flying Capacitor
B1
SD_RC
Active-Low Shutdown, Right Channel
B2
SD_LC
Active-Low Shutdown, Left Channel
B4
PGND
Power Ground
C1
L_IN
Left Channel Input
C2
R_OUT
Right Channel Input
C4
CCP-
Negative Terminal - Charge Pump Flying Capacitor
D1
+AVDD
Positive Power Supply - Amplifier
D2
L_OUT
Left Channel Output
D3
-AVDD
Negative Power Supply - Amplifier
D4
VCP_OUT
Charge Pump Power Output
3
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LM4926
Absolute Maximum Ratings (Note 2)
Junction Temperature
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Thermal Resistance
Supply Voltage
θJA (typ) TLE1411A (Note 11)
4.5V
Storage Temperature
Temperature Range
-0.3V to VDD + 0.3V
Power Dissipation (Note 3)
Internally Limited
ESD Susceptibility (Note 4)
2000V
ESD Susceptibility (Note 5)
200V
86˚C/W
Operating Ratings
−65˚C to +150˚C
Input Voltage
150˚C
TMIN ≤ TA ≤ TMAX
−40˚C ≤ TA ≤ 85˚C
Supply Voltage (VDD)
1.6V ≤ VDD ≤ 4.2V
Electrical Characteristics VDD = 3V
(Note 1)
The following specifications apply for VDD = 3V and 16Ω load unless otherwise specified. Limits apply to TA = 25˚C.
Symbol
Parameter
Conditions
LM4926
Typ
(Note 6)
Quiescent Power Supply Current VIN = 0V, inputs terminated
Auto Standby Mode
both channels enabled
IDD
VIN = 0V, inputs terminated
Quiescent Power Supply Current both channels enabled
Full Power Mode
VIN = 0V, inputs terminated
one channel enabled
Limit
(Notes 7, 8)
2.3
7
Units
(Limits)
mA
10
5
mA (max)
mA
ISD
Shutdown Current
VSD_LC = VSD_RC = GND
0.1
1.8
µA (max)
VOS
Output Offset Voltage
RL = 32Ω, VIN = 0V
0.7
5
mV (max)
AV
Voltage Gain
∆AV
Gain Match
RIN
PO
THD+N
–1.5
Input Resistance
Output Power
Total Harmonic Distortion +
Noise
V/V
1
20
%
15
25
kΩ (min)
kΩ (max)
THD+N = 1% (max); f = 1kHz,
RL = 16Ω, one channel
80
mW
THD+N = 1% (max); f = 1kHz,
RL = 32Ω, one channel
65
mW
THD+N = 1% (max); f = 1kHz,
RL = 16Ω, (two channels in phase)
43
38
mW (min)
THD+N = 1% (max); f = 1kHz,
RL = 32Ω, (two channels in phase)
50
45
mW (min)
PO = 60mW, f = 1kHz, RL = 16Ω
single channel
0.04
PO = 50mW, f = 1kHz, RL = 32Ω
single channel
0.03
%
VRIPPLE = 200mVp-p, Input Referred
PSRR
Power Supply Rejection Ratio
Full Power Mode
SNR
Signal-to-Noise Ratio
VIH
f = 217Hz
70
f = 1kHz
65
f = 20kHz
50
RL = 32Ω, POUT = 20mW,
(A-weighted)
f = 1kHz, BW = 20Hz to 22kHz
dB
100
dB
Shutdown Input Voltage High
VIH =
0.7*CPVDD
V
VIL
Shutdown Input Voltage Low
VIL =
0.3*CPVDD
V
TWU
Wake Up Time From Shutdown
5
µs
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LM4926
Electrical Characteristics VDD = 3V
(Note 1) (Continued)
The following specifications apply for VDD = 3V and 16Ω load unless otherwise specified. Limits apply to TA = 25˚C.
Symbol
Parameter
Conditions
LM4926
Typ
(Note 6)
XTALK
Crosstalk
RL = 16Ω, PO = 1.6mW,
f = 1kHz
ZOUT
Output Impedance
Input Terminated
Input not terminated
IL
Input Leakage
VIN THRESH
Input Voltage Threshold
60
∞
60
Limit
(Notes 7, 8)
Units
(Limits)
dB
kΩ
± 0.1
nA
2.8
mVp
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 that
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, θJA, and the ambient temperature, TA. The maximum
allowable power dissipation is PDMAX = (TJMAX - TA) / θJA or the number given in Absolute Maximum Ratings, whichever is lower. For the LM4926, see power
de-rating 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: If the product is in shutdown mode and VDD exceeds 4.2V (to a max of 4.5V VDD), then most of the excess current will flow through the ESD protection
circuits. If the source impedance limits the current to a max of 10mA, then the part will be protected. If the part is enabled when VDD is above 4.5V, circuit
performance will be curtailed or the part may be permanently damaged.
Note 10: Human body model, 100pF discharged through a 1.5kΩ resistor.
Note 11: θJA value is measured with the device mounted on a PCB with a 3” x 1.5”, 1oz copper heatsink.
External Components Description
Components
(Figure 1)
Functional Description
1.
Ci
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.
2.
C1
Flying capacitor. Low ESR ceramic capacitor (≤100mΩ)
3.
C2
Output capacitor. Low ESR ceramic capacitor (≤100mΩ)
4.
C3
Tantalum capacitor. 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.
5.
C4
Ceramic capacitor. 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.
5
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LM4926
Typical Performance Characteristics
THD+N vs Frequency
VDD = 1.6V, RL = 32Ω, PO = 1mW
THD+N vs Frequency
VDD = 1.6V, RL = 16Ω, PO = 1mW
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THD+N vs Frequency
VDD = 1.8V, RL = 32Ω, PO = 5mW
THD+N vs Frequency
VDD = 1.8V, RL = 16Ω, PO = 5mW
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Frequency
VDD = 3V, RL = 16Ω, PO = 50mW
THD+N vs Frequency
VDD = 3V, RL = 32Ω, PO = 50mW
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THD+N vs Frequency
VDD = 3.6V, RL = 32Ω, PO = 100mW
THD+N vs Frequency
VDD = 3.6V, RL = 16Ω, PO = 100mW
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Frequency
VDD = 4.2V, RL = 16Ω, PO = 150mW
THD+N vs Frequency
VDD = 4.2V, RL = 32Ω, PO = 150mW
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THD+N vs Output Power
VDD = 1.6V, RL = 32Ω, f = 1kHz
One channel enabled
THD+N vs Output Power
VDD = 1.6V, RL = 16Ω, f = 1kH
One channel enabled
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Output Power
VDD = 1.6V, RL = 16Ω, f = 1kHz
Two channels in phase
THD+N vs Output Power
VDD = 1.6V, RL = 32Ω, f = 1kHz
Two channels in phase
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THD+N vs Output Power
VDD = 1.8V, RL = 32Ω, f = 1kHz
One channel enabled
THD+N vs Output Power
VDD = 1.8V, RL = 16Ω, f = 1kHz
One channel enabled
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Output Power
VDD = 1.8V, RL = 16Ω, f = 1kHz
Two channels in phase
THD+N vs Output Power
VDD = 1.8V, RL = 32Ω, f = 1kHz
Two channels in phase
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THD+N vs Output Power
VDD = 3.0V, RL = 32Ω, f = 1kHz
One channel enabled
THD+N vs Output Power
VDD = 3.0V, RL = 16Ω, f = 1kHz
One channel enabled
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Output Power
VDD = 3.0V, RL = 16Ω, f = 1kHz
Two channels in phase
THD+N vs Output Power
VDD = 3.0V, RL = 32Ω, f = 1kHz
Two channels in phase
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THD+N vs Output Power
VDD = 3.6V, RL = 32Ω, f = 1kHz
One channel enabled
THD+N vs Output Power
VDD = 3.6V, RL = 16Ω, f = 1kHz
One channel enabled
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Output Power
VDD = 3.6V, RL = 16Ω, f = 1kHz
Two channels in phase
THD+N vs Output Power
VDD = 3.6V, RL = 32Ω, f = 1kHz
two channels in phase
201161F5
201161F7
THD+N vs Output Power
VDD = 4.2V, RL = 32Ω, f = 1kHz
One channel enabled
THD+N vs Output Power
VDD = 4.2V, RL = 16Ω, f = 1kHz
One channel enabled
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LM4926
Typical Performance Characteristics
(Continued)
THD+N vs Output Power
VDD = 4.2V, RL = 16Ω, f = 1kHz
Two channels in phase
THD+N vs Output Power
VDD = 4.2V, RL = 32Ω, f = 1kHz
Two channels in phase
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PSRR vs Frequency
VDD = 1.6V, RL = 32Ω
PSRR vs Frequency
VDD = 1.6V, RL = 16Ω
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LM4926
Typical Performance Characteristics
(Continued)
PSRR vs Frequency
VDD = 3V, RL = 16Ω
PSRR vs Frequency
VDD = 3V, RL = 32Ω
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PSRR vs Frequency
VDD = 4.2V, RL = 32Ω
PSRR vs Frequency
VDD = 4.2V, RL = 16Ω
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LM4926
Typical Performance Characteristics
(Continued)
Output Power vs Supply Voltage
RL = 16Ω, one channel
Output Power vs Supply Voltage
RL = 32Ω, one channel
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Output Power vs Supply Voltage
RL = 32Ω, 2 channels in phase
Output Power vs Supply Voltage
RL = 16Ω, 2 channels in phase
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LM4926
Typical Performance Characteristics
(Continued)
Supply Current vs Supply Voltage
RL = 16Ω
Representation of Automatic Standby Mode Behavior
VDD = 3V
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Power dissipation is a major concern when using any power
amplifier and must be thoroughly understood to ensure a
successful design. 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.
SUPPLY VOLTAGE SEQUENCING
It is a good general practice to first apply the supply voltage
to a CMOS device before any other signal or supply on other
pins. This is also true for the LM4926 audio amplifier which is
a CMOS device.
PDMAX = (VDD)
Before applying any signal to the inputs or shutdown pins of
the LM4926, it is important to apply a supply voltage to the
VDD pins. After the device has been powered, signals may
be applied to the shutdown pins (see MICRO POWER
SHUTDOWN) and input pins.
2
/ (2π2RL)
(1)
Since the LM4926 has two operational amplifiers in one
package, the maximum internal power dissipation point is
twice that of the number which results from Equation 1. Even
with large internal power dissipation, the LM4926 does not
require heat sinking over a large range of ambient temperatures. From Equation 1, assuming a 3V power supply and a
16Ω load, the maximum power dissipation point is 28mW per
amplifier. Thus the maximum package dissipation point is
56mW. The maximum power dissipation point obtained must
not be greater than the power dissipation that results from
Equation 2:
ELIMINATING THE OUTPUT COUPLING CAPACITOR
The LM4926 features a low noise inverting charge pump that
generates an internal negative supply voltage. This allows
the outputs of the LM4926 to be biased about GND instead
of a nominal DC voltage, like traditional headphone amplifiers. Because there is no DC component, the large DC
blocking capacitors (typically 220µF) are not necessary. The
coupling capacitors are replaced by two, small ceramic
charge pump capacitors, saving board space and cost.
Eliminating the output coupling capacitors also improves low
frequency response. In traditional headphone amplifiers, the
headphone impedance and the output capacitor form a high
pass filter that not only blocks the DC component of the
output, but also attenuates low frequencies, impacting the
bass response. Because the LM4926 does not require the
output coupling capacitors, the low frequency response of
the device is not degraded by external components.
In addition to eliminating the output coupling capacitors, the
ground referenced output nearly doubles the available dynamic range of the LM4926 when compared to a traditional
headphone amplifier operating from the same supply voltage.
PDMAX = (TJMAX - TA) / (θJA)
(2)
For the micro SMD package, θJA = 105˚C/W. TJMAX = 150˚C
for the LM4926. Depending on the ambient temperature, TA,
of the system surroundings, Equation 2 can be used to find
the maximum internal power dissipation supported by the IC
packaging. If the result of Equation 1 is greater than that of
Equation 2, then either the supply voltage must be decreased, the load impedance increased or TA reduced. For
the typical application of a 3V power supply, with a 16Ω load,
the maximum ambient temperature possible without violating
the maximum junction temperature is approximately 144˚C
provided that device operation is around the maximum
power dissipation point. 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.
OUTPUT TRANSIENT (’CLICK AND POPS’)
ELIMINATED
The LM4926 contains advanced circuitry that virtually eliminates output transients (’clicks and pops’). This circuitry
prevents all traces of transients when the supply voltage is
first applied or when the part resumes operation after coming
out of shutdown mode.
POWER SUPPLY BYPASSING
As with any power amplifier, proper supply bypassing is
critical for low noise performance and high power supply
rejection. Applications that employ a 3V power supply typically use a 4.7µF capacitor in parallel with a 0.1µF ceramic
filter capacitor to stabilize the power supply’s output, reduce
noise on the supply line, and improve the supply’s transient
response. Keep the length of leads and traces that connect
capacitors between the LM4926’s power supply pin and
ground as short as possible.
AMPLIFIER CONFIGURATION EXPLANATION
As shown in Figure 2, the LM4926 has two internal operational amplifiers. The two amplifiers have internally configured gain, the closed loop gain is set by selecting the ratio of
Rf to Ri. Consequently, the gain for each channel of the IC is
AUTOMATIC STANDBY MODE
The LM4926 features Automatic Standby Mode circuitry
(patent pending). In the absence of an input signal, after
approximately 12 seconds, the LM4926 goes into low current standby mode. The LM4926 recovers into full power
operating mode immediately after a signal, which is greater
than the input threshold voltage, is applied to either the left or
right input pins. The input threshold voltage is not a static
value, as the supply voltage increases, the input threshold
voltage decreases. This feature reduces power supply current consumption in battery operated applications. Please
see also the graph entitled Representation of Automatic
Standby Mode Behavior in the Typical Performance Characteristics section.
AV = -(Rf / Ri) = 1.5 V/V
where RF = 30kΩ and Ri = 20kΩ.
Since this is an output ground-referenced amplifier, by driving the headphone through ROUT (Pin C2) and LOUT (Pin
D2), the LM4926 does not require output coupling capacitors. The typical single-ended amplifier configuration requires large, expensive output capacitors.
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LM4926
POWER DISSIPATION
Application Information
LM4926
Application Information
negative supply. Higher ESR capacitors result in reduced
output power from the audio amplifiers.
Charge pump load regulation and output impedance are
affected by the value of the flying capacitor (C1). A larger
valued C1 (up to 3.3uF) improves load regulation and minimizes charge pump output resistance. Beyond 3.3uF, the
switch-on resistance dominates the output impedance for
capacitor values above 2.2uF.
(Continued)
To ensure correct operation of Automatic Standby Mode,
proper layout techniques should be implemented. Separating PGND and SGND can help reduce noise entering the
LM4926 in noisy environments. Auto Standby mode works
best when output impedance of the audio source driving
LM4926 is equal or less than 50 Ohms. While Automatic
Standby Mode reduces power consumption very effectively
during silent periods, maximum power saving is achieved by
putting the device into shutdown when it is not in use.
The output ripple is affected by the value and ESR of the
output capacitor (C2). Larger capacitors reduce output ripple
on the negative power supply. Lower ESR capacitors minimize the output ripple and reduce the output impedance of
the charge pump.
MICRO POWER SHUTDOWN
The voltage applied to the SD_LC (shutdown left channel)
pin and the SD_RC (shutdown right channel) pin controls the
LM4926’s shutdown function. When active, the LM4926’s
micropower shutdown feature turns off the amplifiers’ bias
circuitry, reducing the supply current. The trigger point is
0.3*CPVDD for a logic-low level, and 0.7*CPVDD for logichigh level. The low 0.01µA (typ) shutdown current is
achieved by applying a voltage that is as near as ground a
possible to the SD_LC/SD_RC pins. 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 microcontroller. When using a switch,
connect an external 100kΩ pull-up resistor between the
SD_LC/SD_RC pins and VDD. Connect the switch between
the SD_LC/SD_RC pins and ground. Select normal amplifier
operation by opening the switch. Closing the switch connects the SD_LC/SD_RC pins to ground, activating micropower shutdown. The switch and resistor guarantee that the
SD_LC/SD_RC pins will not float. This prevents unwanted
state changes. In a system with a microprocessor or microcontroller, use a digital output to apply the control voltage to
the SD_LC/SD_RC pins. Driving the SD_LC/SD_RC pins
with active circuitry eliminates the pull-up resistor.
The LM4926 charge pump design is optimized for 2.2uF, low
ESR, ceramic, flying, and output capacitors.
Input Capacitor Value Selection
Amplifying the lowest audio frequencies requires high value
input coupling capacitors (Ci in Figure 1). A high value capacitor can be expensive and may compromise space efficiency in portable designs. In many cases, however, the
speakers used in portable systems, whether internal or external, have little ability to reproduce signals below 150Hz.
Applications using speakers with this limited frequency response reap little improvement by using high value input and
output capacitors.
Besides affecting system cost and size, Ci has an effect on
the LM4926’s click and pop performance. The magnitude of
the pop is directly proportional to the input capacitor’s size.
Thus, pops can be minimized by selecting an input capacitor
value that is no higher than necessary to meet the desired
−3dB frequency.
As shown in Figure 1, the internal input resistor, Ri and the
input capacitor, Ci, produce a -3dB high pass filter cutoff
frequency that is found using Equation (3). Conventional
headphone amplifiers require output capacitors; Equation (3)
can be used, along with the value of RL, to determine towards the value of output capacitor needed to produce a
–3dB high pass filter cutoff frequency.
SELECTING PROPER EXTERNAL COMPONENTS
Optimizing the LM4926’s performance requires properly selecting external components. Though the LM4926 operates
well when using external components with wide tolerances,
best performance is achieved by optimizing component values.
fi-3dB = 1 / 2πRiCi
Also, careful consideration must be taken in selecting a
certain type of capacitor to be used in the system. Different
types of capacitors (tantalum, electrolytic, ceramic) have
unique performance characteristics and may affect overall
system performance. (See the section entitled Charge Pump
Capacitor Selection.)
Charge Pump Capacitor Selection
Use low ESR (equivalent series resistance) ( < 100mΩ) ceramic capacitors with an X7R dielectric for best performance. Low ESR capacitors keep the charge pump output
impedance to a minimum, extending the headroom on the
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(3)
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LM4926
Application Information
(Continued)
LM4926 micro SMD DEMO BOARD ARTWORK
Top Overlay
Top Layer
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Mid Layer 1
Mid Layer 2
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LM4926
Application Information
(Continued)
Bottom Layer
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LM4926
Revision History
Rev
Date
Description
1.0
6/22/05
Initial WEB release.
1.1
6/24/05
Added Mid Layer 1 and Mid Layer 2 boards, then re-released D/S to the WEB (per Nisha P.)
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LM4926 Ground-Referenced, Ultra Low Noise, Fixed Gain, 80mW Stereo Headphone Amplifier
Physical Dimensions
inches (millimeters) unless otherwise noted
14 – Bump micro SMD
Order Number LM4926TL
NS Package Number TLE1411A
X1 = 1.970 ± 0.03mm, X2 = 1.970 ± 0.03mm, X3 = 0.600 ± 0.075mm,
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.
For the most current product information visit us at www.national.com.
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National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain
no ‘‘Banned Substances’’ as defined in CSP-9-111S2.
Leadfree products are RoHS compliant.
National Semiconductor
Americas Customer
Support Center
Email: [email protected]
Tel: 1-800-272-9959
www.national.com
National Semiconductor
Europe Customer Support Center
Fax: +49 (0) 180-530 85 86
Email: [email protected]
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
National Semiconductor
Asia Pacific Customer
Support Center
Email: [email protected]
National Semiconductor
Japan Customer Support Center
Fax: 81-3-5639-7507
Email: [email protected]
Tel: 81-3-5639-7560