LM4864
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SNAS109F – SEPTEMBER 1999 – REVISED MAY 2013
LM4864
725mW Audio Power Amplifier with Shutdown
Mode
Check for Samples: LM4864
FEATURES
DESCRIPTION
1
•
•
23
•
•
•
VSSOP, SOIC, PDIP , and WSON Packaging
No Output Coupling Capacitors, Bootstrap
Capacitors, or Snubber Circuits are Necessary
Thermal Shutdown Protection Circuitry
Unity-Gain Stable
External Gain Configuration Capability
(1)
APPLICATIONS
•
•
•
Cellular phones
Personal computers
General purpose audio
KEY SPECIFICATIONS
•
(1)
(2)
PO at 1% THD+N with VDD = 5V, 1kHz
– LM4864LD, 4Ω load 625 mW (typ)
– LM4864LD, 8Ω load 725 mW (typ)
– LM4864M & LM4864N (1), 8Ω load 675 mW
(typ)
– LM4864MM, 8Ω load (2) 300 mW (typ)
– LM4864, 16Ω load 550 mW (typ)
– Shutdown current 0.7 µA (typ)
The LM4864 is a bridged audio power amplifier
capable of delivering 725mW of continuous average
power into an 8Ω load with 1% THD+N from a 5V
power supply.
Boomer® audio power amplifiers were designed
specifically to provide high quality output power from
a low supply voltage while requiring a minimal
amount of external components. Since the LM4864
does not require output coupling capacitors, bootstrap
capacitors or snubber networks, it is optimally suited
for low-power portable applications.
The LM4864 features an externally controlled, low
power consumption shutdown mode, and thermal
shutdown protection.
The closed loop response of the unity-gain stable
LM4864 can be configured by external gain-setting
resistors. The device is available in multiple package
types to suit various applications.
Not recommended for new designs. Contact TI Audio
Marketing.
The DGK0008BA package is thermally limited to 595 mW of
power dissipation at room temperature. Referring to Figure 21
in Typical Performance Characteristics, the power dissipation
limitation for the package occurs at 300 mW of output power.
This package limitation is based on 25°C ambient
temperature and θJA = 210°C. For higher output power
possibilities refer to POWER DISSIPATION.
1
2
3
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.
Boomer is a registered trademark of Texas Instruments.
All other 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 © 1999–2013, Texas Instruments Incorporated
LM4864
SNAS109F – SEPTEMBER 1999 – REVISED MAY 2013
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Typical Application
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagram
Figure 2. VSSOP, SOIC, and PDIP Package- Top View
See Package Number DGK0008A, D0008A or P0008E (3)
Figure 3. WSON Package- Top View
See Package Number NGY0010A
(3)
2
Not recommended for new designs. Contact TI Audio Marketing.
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Figure 4. DIE LAYOUT (B-STEP)
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.
Absolute Maximum Ratings
(1) (2)
Supply Voltage
6.0V
−65°C to +150°C
Storage Temperature
−0.3V to VDD + 0.3V
Input Voltage
Power Dissipation
(3)
Internally limited
ESD Susceptibility
(4)
2000V
ESD Susceptibility
(5)
200V
Junction Temperature
Soldering
Information
Thermal Resistance
(1)
(2)
(3)
(4)
(5)
(6)
150°C
Small Outline Package
Vapor Phase (60 sec.)
215°C
Infrared (15 sec.)
220°C
θJC (VSSOP)
56° C/W
θJA (VSSOP)
210°C/W
θJC (SOIC)
35°C/W
θJA (SOIC)
170°C/W
θJC (PDIP)*
37°C/W
θJA (PDIP)*
107°C/W
θJA (WSON)
(6)
63°C/W
θJC (WSON)
(6)
12°C/W
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 ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not specified for parameters where no limit is given, however, the typical value is a good indication
of device performance.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
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 the Absolute Maximum Ratings,
whichever is lower. For the LM4864, TJMAX = 150°C. The typical junction-to-ambient thermal resistance, when board mounted, is
230°C/W for package number DGK0008A, 170°C/W for package number D0008A and is 107°C/W for package number P0008E*.
Human body model, 100pF discharged through a 1.5kΩ resistor.
Machine Model, 220pF – 240pF discharged through all pins.
The NGY0010A package has its exposed-DAP soldered to an exposed 1.2in2 area of 1oz printed circuit board copper.
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Operating Ratings
TMIN ≤ TA ≤ TMAX
Temperature Range
−40°C ≤ TA ≤ +85°C
2.7V ≤ VDD ≤ 5.5V
Supply Voltage
Electrical Characteristics VDD = 5V
(1) (2)
The following specifications apply for VDD = 5V, for all available packages, unless otherwise specified. Limits apply for TA =
25°C
Symbol
Parameter
Conditions
(6)
LM4864
Typical
(3)
Limit
(4) (5)
Units
(Limits)
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A
ISD
Shutdown Current
VPIN1 = VDD
3.6
6.0
0.7
5
VOS
Output Offset Voltage
VIN = 0V
μA (max)
5
50
mV (max)
PO
Output Power
THD = 1% (max); f = 1 kHz; RL = 4Ω;
LM4864LD (7)
625
mW (min)
THD = 1% (max); f = 1 kHz; RL = 8Ω;
LM4864LD (7)
725
mW (min)
THD = 1% (max); f = 1 kHz; RL = 8Ω;
LM4864MM (8)
300
THD = 1% (max); f = 1 kHz; RL = 8Ω;
LM4864M and LM4864N*
675
300
mA (max)
mW (min)
mW (min)
THD+N = 1%; f = 1 kHz; RL = 16Ω;
550
THD+N
Total Harmonic Distortion+Noise
PO = 300 mWrms; AVD = 2; RL = 8Ω;
20 Hz ≤ f ≤ 20 kHz, BW < 80kHz
0.7
%
PSRR
Power Supply Rejection Ratio
VDD = 4.9V–5.1V
50
dB
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
4
mW
All voltages are measured with respect to the ground pin, unless otherwise specified.
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 ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not specified for parameters where no limit is given, however, the typical value is a good indication
of device performance.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to TI's AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test, or statistical analysis.
The quiescent power supply current depends on the offset voltage when a practical load is connected to the amplifier.
The NGY0010A package has its exposed-DAP soldered to an exposed 1.2in2 area of 1oz printed circuit board copper.
The DGK0008BA package is thermally limited to 595 mW of power dissipation at room temperature. Referring to Figure 21 in Typical
Performance Characteristics, the power dissipation limitation for the package occurs at 300 mW of output power. This package limitation
is based on 25°C ambient temperature and θJA = 210°C. For higher output power possibilities refer to POWER DISSIPATION.
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Electrical Characteristics VDD = 3V
(1) (2)
The following specifications apply for VDD = 3V, for all available packages, unless otherwise specified. Limits apply for TA =
25°C
Symbol
Parameter
Conditions
IDD
Quiescent Power Supply Current
VIN = 0V, IO = 0A
ISD
Shutdown Current
VPIN1 = VDD
VOS
Output Offset Voltage
VIN = 0V
PO
Output Power
THD+N
Total Harmonic Distortion+Noise
PSRR
Power Supply Rejection Ratio
(1)
(2)
(3)
(4)
(5)
(6)
(6)
LM4864
Typical
(3)
Limit
(4) (5)
Units
(Limits)
1.0
3.0
mA (max)
0.3
2.0
μA (max)
5
mV
THD = 1% (max); f = 1 kHz; RL = 8Ω
200
mW
THD = 1% (max); f = 1 kHz; RL = 16Ω
175
mW
PO = 100 mWrms; AVD = 2; RL = 8Ω;
20 Hz ≤ f ≤ 20 kHz, BW < 80 kHz
1.5
%
VDD = 2.9V–3.1V
50
dB
All voltages are measured with respect to the ground pin, unless otherwise specified.
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 ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not specified for parameters where no limit is given, however, the typical value is a good indication
of device performance.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to TI's AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test, or statistical analysis.
The quiescent power supply current depends on the offset voltage when a practical load is connected to the amplifier.
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External Components Description
(See Figure 1)
Components
Functional Description
1.
Ri
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/(2π RiCI).
2.
Ci
Input coupling capacitor which blocks the DC voltage at the amplifier's input terminals. Also creates a highpass filter with Ri
at fc = 1/(2π RiCi). Refer to PROPER SELECTION OF EXTERNAL COMPONENTS for an explanation of how to determine
the value of Ci.
3.
RF
Feedback resistance which sets the closed-loop gain in conjunction with Ri.
4.
CS
Supply bypass capacitor which provides power supply filtering. Refer to POWER SUPPLY BYPASSING section for
information concerning proper placement and selection of the supply bypass capacitor.
5.
CB
Bypass pin capacitor which provides half-supply filtering. Refer to PROPER SELECTION OF EXTERNAL COMPONENTS
for information concerning proper placement and selection of CB.
6
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Typical Performance Characteristics
THD+N
vs
Frequency
THD+N
vs
Frequency
Figure 5.
Figure 6.
THD+N
vs
Frequency
THD+N
vs
Frequency
Figure 7.
Figure 8.
THD+N
vs
Frequency
THD+N
vs
Frequency
Figure 9.
Figure 10.
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Typical Performance Characteristics (continued)
8
THD+N
vs
Output Power
THD+N
vs
Output Power
Figure 11.
Figure 12.
THD+N
vs
Output Power
THD+N
vs
Output Power
Figure 13.
Figure 14.
THD+N
vs
Output Power
THD+N
vs
Output Power
Figure 15.
Figure 16.
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Typical Performance Characteristics (continued)
Output Power vs
Supply Voltage
Output Power vs
Supply Voltage
Figure 17.
Figure 18.
Output Power vs
Supply Voltage
Output Power vs
Load Resistance
Figure 19.
Figure 20.
Power Dissipation vs
Output Power
Power Derating Curve
Figure 21.
Figure 22.
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Typical Performance Characteristics (continued)
10
Dropout Voltage vs
Supply Voltage
Noise Floor
Figure 23.
Figure 24.
Frequency Response vs
Input Capacitor Size
Power Supply
Rejection Ratio
Figure 25.
Figure 26.
Open Loop
Frequency Response
Supply Current vs
Supply Voltage
Figure 27.
Figure 28.
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Typical Performance Characteristics for the LM4864LD
(1)
(1)
THD+N
vs
Frequency
THD+N
vs
Frequency
Figure 29.
Figure 30.
THD+N
vs
Power Out
THD+N
vs
Power Out
Figure 31.
Figure 32.
Output Power
vs
Supply Voltage
Power Dissipation
vs
Output Power
Figure 33.
Figure 34.
The NGY0010A package has its exposed-DAP soldered to an exposed 1.2in2 area of 1oz printed circuit board copper.
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APPLICATION INFORMATION
BRIDGE CONFIGURATION EXPLANATION
As shown in Figure 1, the LM4864 has two operational amplifiers internally, allowing for a few different amplifier
configurations. The first amplifier's gain is externally configurable, while the second amplifier is internally fixed in
a unity-gain, inverting configuration. The closed-loop gain of the first amplifier is set by selecting the ratio of RF to
Ri while the second amplifier's gain is fixed by the two internal 10kΩ resistors. Figure 1 shows that the output of
amplifier one serves as the input to amplifier two which results in both amplifiers producing signals identical in
magnitude, but out of phase 180°. Consequently, the differential gain for the IC is
AVD = 2*(RF/Ri)
(1)
By driving the load differentially through outputs Vo1 and Vo2, an amplifier configuration commonly referred to as
“bridged mode” is established. Bridged mode operation is different from the classical single-ended amplifier
configuration where one side of its load is connected to ground.
A bridge amplifier design has a few distinct advantages over the single-ended configuration, as it provides
differential drive to the load, thus doubling output swing for a specified supply voltage. Four times the output
power is possible as compared to a single-ended amplifier under the same conditions. This increase in attainable
output power assumes that the amplifier is not current limited or clipped. In order to choose an amplifier's closedloop gain without causing excessive clipping, please refer to AUDIO POWER AMPLIFIER DESIGN section.
A bridge configuration, such as the one used in LM4864, also creates a second advantage over single-ended
amplifiers. Since the differential outputs, Vo1 and Vo2, are biased at half-supply, no net DC voltage exists across
the load. This eliminates the need for an output coupling capacitor which is required in a single supply, singleended amplifier configuration. If an output coupling capacitor is not used in a single-ended configuration, the halfsupply bias across the load would result in both increased internal lC power dissipation as well as permanent
loudspeaker damage.
POWER DISSIPATION
Power dissipation is a major concern when designing a successful amplifier, whether the amplifier is bridged or
single-ended. Equation 2 states the maximum power dissipation point for a bridge amplifier operating at a given
supply voltage and driving a specified output load.
PDMAX = (VDD)2/(2π2RL)
Single-Ended (1)
(2)
However, a direct consequence of the increased power delivered to the load by a bridge amplifier is an increase
in internal power dissipation point for a bridge amplifier operating at the same conditions.
PDMAX = 4(VDD)2/(2π2RL)
Bridge Mode (2)
(3)
Since the LM4864 has two operational amplifiers in one package, the maximum internal power dissipation is 4
times that of a single-ended amplifier. Even with this substantial increase in power dissipation, the LM4864 does
not require heatsinking. From Equation 2, assuming a 5V power supply and an 8Ω load, the maximum power
dissipation point is 633 mW. The maximum power dissipation point obtained from Equation 3 must not be greater
than the power dissipation that results from Equation 4:
PDMAX = (TJMAX − TA)/θJA
(3)
(4)
For package DGK0008A, θJA = 210°C/W, for package D00008A, θJA = 170°C/W, for package P0008E, θJA =
107°C/W, and for package NGY0010A, θJA = 63°C/W. TJMAX = 150°C for the LM4864. Depending on the ambient
temperature, TA, of the system surroundings, Equation 4 can be used to find the maximum internal power
dissipation supported by the IC packaging. If the result of Equation 3 is greater than that of Equation 4, then
either the supply voltage must be decreased, the load impedance increased, the ambient temperature reduced,
or the θJA reduced with heatsinking. In many cases larger traces near the output, VDD, and GND pins can be
used to lower the θJA. The larger areas of copper provide a form of heatsinking allowing a higher power
dissipation. For the typical application of a 5V power supply, with an 8Ω load, the maximum ambient temperature
possible without violating the maximum junction temperature is approximately 44°C provided that device
operation is around the maximum power dissipation point and assuming surface mount packaging. Internal
power dissipation is a function of output power. If typical operation is not around the maximum power dissipation
point, the ambient temperature can be increased. Refer to Typical Performance Characteristics for power
dissipation information for lower output powers.
12
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EXPOSED-DAP PACKAGE PCB MOUNTING CONSIDERATION
The LM4864's exposed-dap (die attach paddle) package (NGY) provides a low thermal resistance between the
die and the PCB to which the part is mounted and soldered. This allows rapid heat transfer from the die to the
surrounding PCB copper traces, ground plane, and surrounding air.
The NGY package should have its DAP soldered to a copper pad on the PCB. The DAP's PCB copper pad may
be connected to a large plane of continuous unbroken copper. This plane forms a thermal mass, heat sink, and
radiation area.
Further detailed and specific information concerning PCB layout, fabrication, and mounting an NGY (WSON)
package is available from Texas Instruments's Package Engineering Group under application note AN1187.
POWER SUPPLY BYPASSING
As with any power amplifier, proper supply bypassing is critical for low noise performance and high power supply
rejection. The capacitor location on both the bypass and power supply pins should be as close to the device as
possible. The effect of a larger half supply bypass capacitor is improved PSRR due to increased half-supply
stability. Typical applications employ a 5V regulator with 10 μF and a 0.1 μF bypass capacitors which aid in
supply stability, but do not eliminate the need for bypassing the supply nodes of the LM4864. The selection of
bypass capacitors, especially CB, is thus dependent upon desired PSRR requirements, click and pop
performance as explained in PROPER SELECTION OF EXTERNAL COMPONENTS, system cost, and size
constraints.
SHUTDOWN FUNCTION
In order to reduce power consumption while not in use, the LM4864 contains a shutdown pin to externally turn off
the amplifier's bias circuitry. This shutdown feature turns the amplifier off when a logic high is placed on the
shutdown pin. The trigger point between a logic low and logic high level is typically half supply. It is best to switch
between ground and supply to provide maximum device performance. By switching the shutdown pin to VDD, the
LM4864 supply current draw will be minimized in idle mode. While the device will be disabled with shutdown pin
voltages less than VDD, the idle current may be greater than the typical value of 0.7 μA. In either case, the
shutdown pin should be tied to a definite voltage to avoid unwanted state changes.
In many applications, a microcontroller or microprocessor output is used to control the shutdown circuitry which
provides a quick, smooth transition into shutdown. Another solution is to use a single-pole, single-throw switch in
conjunction with an external pull-up resistor. When the switch is closed, the shutdown pin is connected to ground
and enables the amplifier. If the switch is open, then the external pull-up resistor will disable the LM4864. This
scheme ensures that the shutdown pin will not float, thus preventing unwanted state changes.
PROPER SELECTION OF EXTERNAL COMPONENTS
Proper selection of external components in applications using integrated power amplifiers is critical to optimize
device and system performance. While the LM4864 is tolerant to a variety of external component combinations,
consideration to component values must be used to maximize overall system quality.
The LM4864 is unity-gain stable, giving a designer maximum system flexibility. The LM4864 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 1
Vrms are available from sources such as audio codecs. Please refer toAUDIO POWER AMPLIFIER DESIGN, for
a more complete explanation of proper gain selection.
Besides gain, one of the major considerations is the closed-loop bandwidth of the amplifier. To a large extent, the
bandwidth is dictated by the choice of external components shown in Figure 1. 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 for a few distinct reasons.
Selection of Input Capacitor Size
Large input capacitors are both expensive and space hungry for portable designs. Clearly, a certain sized
capacitor is needed to couple in low frequencies without severe attenuation. But in many cases the speakers
used in portable systems, whether internal or external, have little ability to reproduce signals below 150 Hz. In
this case using a large input capacitor may not increase system performance.
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In addition to system cost and size, click and pop performance is effected by the size of the input coupling
capacitor, Ci. A larger input coupling capacitor requires more charge to reach its quiescent DC voltage (nominally
½ VDD). This charge comes from the output via the feedback and is apt to create pops upon device enable. Thus,
by minimizing the capacitor size based on necessary low frequency response, turn-on pops can be minimized.
Besides minimizing the input capacitor size, careful consideration should be paid to the bypass capacitor value.
Bypass capacitor, CB, is the most critical component to minimize turn-on pops since it determines how fast the
LM4864 turns on. The slower the LM4864's outputs ramp to their quiescent DC voltage (nominally ½ VDD), the
smaller the turn-on pop. Choosing CB equal to 1.0 μF along with a small value of Ci (in the range of 0.1 μF to
0.39 μF), should produce a clickless and popless shutdown function. While the device will function properly, (no
oscillations or motorboating), with CB equal to 0.1 μF, the device will be much more susceptible to turn-on clicks
and pops. Thus, a value of CB equal to 1.0 μF or larger is recommended in all but the most cost sensitive
designs.
AUDIO POWER AMPLIFIER DESIGN
Design a 300 mW/8Ω Audio Amplifier
Given:
Power Output
300 mWrms
Load Impedance
8Ω
Input Level
1 Vrms
Input Impedance
20 kΩ
Bandwidth
100 Hz–20 kHz ± 0.25 dB
A designer must first determine the minimum supply rail to obtain the specified output power. By extrapolating
fromFigure 18 and Figure 19 in Typical Performance Characteristics, the supply rail can be easily found. A
second way to determine the minimum supply rail is to calculate the required Vopeak using Equation 5 and add
the dropout voltage. Using this method, the minimum supply voltage would be (Vopeak + (2*VOD)), where VOD is
extrapolated from Figure 23 in Typical Performance Characteristics.
(5)
Using Figure 17 for an 8Ω load, the minimum supply rail is 3.5V. But since 5V is a standard supply voltage in
most applications, it is chosen for the supply rail. Extra supply voltage creates headroom that allows the LM4864
to reproduce peaks in excess of 500 mW without producing audible distortion. At this time, the designer must
make sure that the power supply choice along with the output impedance does not violate the conditions
explained in POWER DISSIPATION.
Once the power dissipation equations have been addressed, the required differential gain can be determined
from Equation 6.
(6)
(7)
RF/Ri = AVD/2
From Equation 6, the minimum AVD is 1.55; use AVD = 2.
Since the desired input impedance was 20 kΩ, and with a AVD of 2, a ratio of 1:1 of RF to Ri results in an
allocation of Ri = RF = 20 kΩ. The final design step is to address the bandwidth requirements which must be
stated as a pair of −3 dB frequency points. Five times away from a pole gives 0.17 dB down from passband
response which is better than the required ±0.25 dB specified.
fL = 100 Hz/5 = 20 Hz
fH = 20 kHz × 5 = 100 kHz
(8)
(9)
As stated in External Components Description , Ri in conjunction with Ci create a highpass filter.
Ci ≥ 1/(2π*20 kΩ*20 Hz) = 0.397 μF; use 0.39 μF
14
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The high frequency pole is determined by the product of the desired high frequency pole, fH, and the differential
gain, AVD. With a AVD = 2 and fH = 100 kHz, the resulting GBWP = 100 kHz which is much smaller than the
LM4864 GBWP of 18 MHz. This figure displays that if a designer has a need to design an amplifier with a higher
differential gain, the LM4864 can still be used without running into bandwidth problems.
LM4864LD DEMO BOARD ARTWORK
Figure 35. Silk Screen View of LM4864LD
Figure 36. Top Layer of LM4864LD
Figure 37. Bottom Layer of LM4864LD
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LM4864 MDC MWC
725MW Audio Power Amplifier With Shutdown Mode
Figure 38. Die Layout (B - Step)
Table 1. DIE/WAFER CHARACTERISTICS
Fabrication Attributes
General Die Information
Physical Die Identification
LM4862B
Bond Pad Opening Size (min)
86µm x 86µm
Die Step
B
Bond Pad Metalization
ALUMINUM
Passivation
NITRIDE
Physical Attributes
Wafer Diameter
150mm
Back Side Metal
Bare Back
Dise Size (Drawn)
1283µm x 952µm
51mils x 37mils
Back Side Connection
GND
Thickness
406µm Nominal
Min Pitch
117µm Nominal
Special Assembly Requirements:
Note: Actual die size is rounded to the nearest micron.
Die Bond Pad Coordinate Locations (B - Step)
(Referenced to die center, coordinates in µm) NC = No Connection
SIGNAL NAME
PAD# NUMBER
X/Y COORDINATES
PAD SIZE
X
Y
X
Y
BYPASS
1
-322
523
86
x
86
GND
2
-359
259
86
x
188
INPUT +
3
-359
5
86
x
86
GND
4
-359
-259
86
x
188
NC
5
-323
-523
86
x
86
INPUT -
6
-109
-523
86
x
86
VOUT 1
7
8
-523
86
x
86
VDD
8
358
-78
86
x
188
GND
9
358
141
86
x
188
NC
10
359
406
86
x
86
NC
11
323
523
86
x
86
VOUT 2
12
8
523
86
x
86
SHUTDOWN
13
-109
523
86
x
86
16
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Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LM4864
LM4864
www.ti.com
SNAS109F – SEPTEMBER 1999 – REVISED MAY 2013
REVISION HISTORY
Changes from Revision E (May 2013) to Revision F
•
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 16
Submit Documentation Feedback
Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LM4864
17
PACKAGE OPTION ADDENDUM
www.ti.com
21-Aug-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
LM4864M/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LM48
64M
Samples
LM4864MM
ACTIVE
VSSOP
DGK
8
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 85
Z64
Samples
LM4864MM/NOPB
ACTIVE
VSSOP
DGK
8
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
Z64
Samples
LM4864MMX/NOPB
ACTIVE
VSSOP
DGK
8
3500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
Z64
Samples
LM4864MX/NOPB
ACTIVE
SOIC
D
8
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LM48
64M
Samples
(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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of