LM4953SD/NOPB [TI]

1 CHANNEL, AUDIO AMPLIFIER, PDSO14, WSON-14;
LM4953SD/NOPB
型号: LM4953SD/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

1 CHANNEL, AUDIO AMPLIFIER, PDSO14, WSON-14

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LM4953, LM4953SDBD  
www.ti.com  
SNAS299F SEPTEMBER 2005REVISED APRIL 2013  
LM4953 Boomer™ Audio Power Amplifier Series Ground-Referenced, Ultra Low Noise,  
Ceramic Speaker Driver  
Check for Samples: LM4953, LM4953SDBD  
1
FEATURES  
DESCRIPTION  
The LM4953 is an audio power amplifier designed for  
driving Ceramic Speaker in portable applications.  
When powered by a 3.6V supply, it is capable of  
forcing 12.6Vpp across a 2μF + 30bridge-tied-load  
(BTL) with less than 1% THD+N.  
23  
Pop & Click Circuitry Eliminates Noise During  
Turn-On and Turn-Off Transitions  
Low, 1μA (Max) Shutdown Current  
Low, 7mA (Typ) Quiescent Current  
12.6Vpp Mono BTL Output, Load = 2μF+ 30Ω  
Thermal Shutdown  
Boomer audio power amplifiers were designed  
specifically to provide high quality output power with a  
minimal amount of external components. The  
LM4953 does not require bootstrap capacitors, or  
snubber circuits. Therefore it is ideally suited for  
display applications requiring high power and minimal  
size.  
Unity-Gain Stable  
External Gain Configuration Capability  
APPLICATIONS  
Cellphone  
PDA  
The LM4953 features a low-power consumption  
shutdown mode. Additionally, the LM4953 features an  
internal thermal shutdown protection mechanism.  
KEY SPECIFICATIONS  
The LM4953 contains advanced pop & click circuitry  
that eliminates noises which would otherwise occur  
during turn-on and turn-off transitions.  
Quiescent Power Supply Current (Vdd = 3V),  
7mA(Typ)  
The LM4953 is unity-gain stable and can be  
configured by external gain-setting resistors.  
BTL Voltage Swing  
(2μF+30load, 1% THD+N, Vdd = 3.6V), 12.6Vpp  
(Typ)  
Shutdown Current, 1µA (Max)  
1
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.  
2
3
Boomer is a 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 © 2005–2013, Texas Instruments Incorporated  
LM4953, LM4953SDBD  
SNAS299F SEPTEMBER 2005REVISED APRIL 2013  
www.ti.com  
Typical Application  
20 kW  
CPV  
DD  
R
f
+
*C  
C
3
4.7 mF  
4.7 mF  
4
10  
2
0.39 mF  
20 kW  
13  
+
15W  
-
11  
R
i
Undervoltage  
Lockout,  
Click/Pop  
C
i
+
Vin1  
Suppression  
and Shutdown  
Control  
1
3
SHUTDOWN  
Ceramic  
Speaker  
2 mF  
Charge  
Pump  
C
1
2.2 mF  
+
-
5
9
15W  
100 kW  
4
6
14  
8
C
2
2.2 mF  
20 kW  
Figure 1. Typical Application Circuit  
Connection Diagram  
1
2
14  
SGND  
SD  
V
CPV  
13  
12  
11  
10  
9
IN  
DD  
CCP+  
NC  
3
4
5
6
7
OUT A  
PGND  
CCP-  
AV  
DD  
V
OUT B  
CP_OUT  
AV  
SS  
NC  
8
Figure 2. WSON Package  
Top View  
See Package Number NHK0014A  
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PIN DESCRIPTIONS  
Pin  
1
Name  
SD  
Function  
Active Low Shutdown  
Charge Pump Power Supply  
2
CPVDD  
CCP+  
3
Positive Terminal - Charge Pump Flying  
Capacitor  
4
5
PGND  
CCP-  
Power Ground  
Negative Terminal - Charge Pump Flying  
Capacitor  
6
VCP_OUT  
NC  
Charge Pump Output  
No Connect  
7
8
AVSS  
OUT B  
AVDD  
OUT A  
NC  
Negative Power Supply - Amplifier  
Output B  
9
10  
11  
12  
13  
14  
Positive Power Supply - Amplifier  
Output A  
No Connect  
VIN  
Signal Input  
SGND  
Signal Ground  
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)(3)  
Supply Voltage (VDD  
)
4.5V  
65°C to +150°C  
-0.3V to VDD + 0.3V  
Internally Limited  
2000V  
Storage Temperature  
Input Voltage  
Power Dissipation(4)  
ESD Susceptibility(5)(6)  
ESD Susceptibility(7)(6)  
200V  
Junction Temperature  
150°C  
Thermal Resistance  
See AN-1187(SNOA401) 'Leadless Leadframe Packaging (LLP).'  
(1) All voltages are measured with respect to the GND pin unless otherwise specified.  
(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 ensure specific performance limits. Electrical Characteristics state DC and AC electrical  
specifications under particular test conditions that ensure specific performance limits. This assumes that the device is within the  
Operating Ratings. Specifications are not ensured for parameters where no limit is given; however, the typical value is a good indication  
of device performance.  
(3) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and  
specifications.  
(4) 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 LM4xxx typical application (shown in Figure 1) with VDD = yyV, RL = 2μF+30mono BTL operation the total  
power dissipation is xxxW. θJA = 40°C/W.  
(5) Human body model, 100pF discharged through a 1.5kresistor.  
(6) If the product is in shutdown mode and VDD exceeds 3.6V (to a max of 4V 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 4V, circuit performance will be curtailed or the part may be permanently damaged.  
(7) Machine Model, 220pF-240pF discharged through all pins.  
Operating Ratings  
Temperature Range  
TMIN TA TMAX  
40°C TA 85°C  
1.6V VDD 4.2V  
Supply Voltage (VDD  
)
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Electrical Characteristics VDD = 3.6V  
The following specifications apply for VDD = 3.6V, AV-BTL = 6dB, ZL = 2μF+30unless otherwise specified. Limits apply to TA =  
25°C. See Figure 1.  
Symbol  
Parameter  
Conditions  
LM4953  
Limit(2)(3)  
Units (Limits)  
Typ(1)  
Quiescent Power Supply  
Current  
IDD  
Istandby  
ISD  
VIN = 0, RLOAD = 2μF+30Ω  
8
mA (max)  
mA  
Quiescent Power Supply  
Current Auto Standby Mode  
VIN = 0, ZLOAD = 2μF+30Ω  
2.7  
0.1  
Shutdown Current  
VSD = GND  
1
µA (max)  
V (min)  
SD1  
SD2  
VSDIH  
Shutdown Voltage Input High  
0.7*CPVdd  
SD1  
SD2  
V (max)  
VSDIL  
Shutdown Voltage Input Low  
0.3*CPVdd  
10  
TWU  
VOS  
Wake-up Time  
125  
1
μsec  
Output Offset Voltage  
mV (max)  
THD = 1% (max); f = 1kHz  
RL = 2μF+30, Mono BTL  
VOUT  
Output Voltage Swing  
12.6  
Vpp  
Total Harmonic Distortion +  
Noise  
THD+N  
VOUT = 6Vp-p, fIN = 1kHz  
0.02  
15  
%
OS  
Output Noise  
A-Weighted Filter, VIN = 0V  
μV  
dB  
VRIPPLE = 200mVp-p, f = 217Hz,  
Input Referred  
67  
PSRR  
SNR  
Power Supply Rejection Ratio  
Signal-to-Noise Ratio  
VRIPPLE = 200mVp-p, f = 1kHz,  
Input Referred  
65  
dB  
dB  
ZL = 2μF+30, VOUT = 6Vp-p  
105  
(1) Typicals are measured at 25°C and represent the parametric norm.  
(2) Limits are specified to Texas Instruments' AOQL (Average Outgoing Quality Level).  
(3) Datasheet min/max specification limits are specified by design, test, or statistical analysis.  
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Electrical Characteristics VDD = 3.0V  
The following specifications apply for VDD = 3.0V, AV-BTL = 6dB, ZL = 2μF+30unless otherwise specified. Limits apply to TA =  
25°C. See Figure 1.  
Symbol  
Parameter  
Conditions  
LM4953  
Limit(2)(3)  
Units (Limits)  
Typ(1)  
Quiescent Power Supply  
Current  
IDD  
Istandby  
ISD  
VIN = 0, ZLOAD = 2μF+30Ω  
7
10  
mA (max)  
mA  
Quiescent Power Supply  
Current Auto Standby Mode  
VIN = 0, ZLOAD = 2μF+30Ω  
2.3  
0.1  
Shutdown Current  
VSD-LC = VSD-RC = GND  
1
µA (max)  
V (min)  
SD1  
SD2  
VSDIH  
Shutdown Voltage Input High  
0.7*CPVdd  
SD1  
SD2  
V (max)  
VSDIL  
Shutdown Voltage Input Low  
0.3*CPVdd  
10  
TWU  
VOS  
Wake-up Time  
125  
1
μsec  
Output Offset Voltage  
mV (max)  
THD = 1% (max); f = 1kHz  
ZL = 2μF+30, Mono BTL  
VOUT  
Output Voltage Swing  
10.2  
Vpp  
Total Harmonic Distortion +  
Noise  
THD+N  
VOUT = 8.5Vp-p, fIN = 1kHz  
0.02  
15  
%
OS  
Output Noise  
A-Weighted Filter, VIN = 0V  
μV  
dB  
VRIPPLE = 200mVp-p, f = 217Hz,  
Input Referred  
73  
PSRR  
SNR  
Power Supply Rejection Ratio  
Signal-to-Noise Ratio  
VRIPPLE = 200mVp-p, f = 1kHz,  
Input Referred  
68  
dB  
dB  
ZL = 2μF+30, VOUT = 8.5Vp-p  
105  
(1) Typicals are measured at 25°C and represent the parametric norm.  
(2) Limits are specified to Texas Instruments' AOQL (Average Outgoing Quality Level).  
(3) Datasheet min/max specification limits are specified by design, test, or statistical analysis.  
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Typical Performance Characteristics  
THD+N vs Frequency  
VDD = 2V, VO = 2Vpp, ZL = 2μF+30Ω  
THD+N vs Frequency  
VDD = 3V, VO = 6Vpp, ZL = 2μF+30Ω  
10  
1
10  
1
0.1  
0.1  
0.01  
0.01  
0.001  
0.001  
20000  
20  
1000  
20000  
100  
20  
100  
1000  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 3.  
Figure 4.  
THD+N vs Frequency  
VDD = 3.6V, VO = 8.5Vpp, ZL = 2μF+30Ω  
THD+N vs Frequency  
VDD = 4.2V, VO = 10Vpp, ZL = 2μF+30Ω  
10  
1
10  
1
0.1  
0.1  
0.01  
0.01  
0.001  
0.001  
20000  
20000  
20  
20  
100  
1000  
1000  
100  
FREQUENCY (Hz)  
FREQUENCY(Hz)  
Figure 5.  
Figure 6.  
THD+N vs Output Voltage  
VDD = 2V, f = 1kHz, ZL = 2μF+30Ω  
THD+N vs Output Voltage  
VDD = 3V, f = 1kHz, ZL = 2μF+30Ω  
10  
1
1
0.1  
0.1  
0.01  
0.01  
0.001  
0.001  
0.5 1.0  
1.5 2.0  
3.0  
4.0  
0.6 0.8  
1
1.2 1.4 1.6 1.8 2.0 2.2 2.4  
2.5  
3.5  
OUTPUT VOLTAGE SWING (Vrms)  
OUTPUT VOLTAGE SWING (Vrms)  
Figure 7.  
Figure 8.  
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Typical Performance Characteristics (continued)  
THD+N vs Output Voltage  
VDD = 3.6V, f = 1kHz, ZL = 2μF+30Ω  
THD+N vs Output Voltage  
VDD = 4.2V, f = 1kHz, ZL = 2μF+30Ω  
10  
10  
1
0.1  
1
0.1  
0.01  
0.001  
0.01  
0.001  
0.5  
1
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0  
1
6
2
3
5
7
4
OUTPUT VOLTAGE SWING (Vrms)  
OUTPUT VOLTAGE SWING (Vrms)  
Figure 9.  
Figure 10.  
PSRR vs Frequency  
VDD = 2V, ZL = 2μF+30Ω  
PSRR vs Frequency  
VDD = 3V, ZL = 2μF+30Ω  
0
0
-10  
-10  
-20  
-30  
-40  
-50  
-60  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-70  
-80  
10  
100  
1k  
10k  
100k  
10  
100  
1k  
10k  
100k  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 11.  
Figure 12.  
PSRR vs Frequency  
VDD = 3.6V, ZL = 2μF+30Ω  
PSRR vs Frequency  
VDD = 4.2V, ZL = 2μF+30Ω  
0
0
-10  
-10  
-20  
-30  
-40  
-50  
-60  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-70  
-80  
10  
100  
1k  
10k  
100k  
10  
100  
1k  
10k  
100k  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 13.  
Figure 14.  
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Typical Performance Characteristics (continued)  
Supply Current vs Supply Voltage  
ZL = 2μF+30Ω  
12  
10  
8
Full Power Mode  
6
Auto-Standby Mode  
4
2
0
4
1.5  
2
3
3.5  
2.5  
SUPPLY VOLTAGE (V)  
Figure 15.  
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APPLICATION INFORMATION  
ELIMINATING THE OUTPUT COUPLING CAPACITOR  
The LM4953 features a low noise inverting charge pump that generates an internal negative supply voltage. This  
allows the outputs of the LM4953 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  
LM4953 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 LM4953 when compared to a traditional headphone amplifier operating from the  
same supply voltage.  
BRIDGE CONFIGURATION EXPLANATION  
The Audio Amplifier portion of the LM4953has two internal amplifiers allowing different amplifier configurations.  
The first amplifier’s gain is externally configurable, whereas 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 20kresistors. Figure 1 shows that the output of amplifier one  
serves as the input to amplifier two. This results in both amplifiers producing signals identical in magnitude, but  
out of phase by 180°. Consequently, the differential gain for the Audio Amplifier is  
AVD = 2 *(Rf/Ri)  
(1)  
By driving the load differentially through outputs OUT A and OUT B, an amplifier configuration commonly referred  
to as “bridged mode” is established. Bridged mode operation is different from the classic single-ended amplifier  
configuration where one side of the load is connected to ground.  
A bridge amplifier design has a few distinct advantages over the single-ended configuration. It provides  
differential drive to the load, thus doubling the 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 closed-  
loop gain without causing excessive clipping, please refer to the Audio Power Amplifier Design section.  
The bridge configuration also creates a second advantage over single-ended amplifiers. Since the differential  
outputs, OUT A and OUT B, 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, single-ended amplifier  
configuration. Without an output coupling capacitor, the half-supply bias across the load would result in both  
increased internal IC power dissipation and also possible loudspeaker damage.  
OUTPUT TRANSIENT ('CLICK AND POPS') ELIMINATED  
The LM4953 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 DISSIPATION  
Power dissipation is a major concern when using any power amplifier and must be thoroughly understood to  
ensure a successful design. Equation 2 states the maximum power dissipation point for a single-ended amplifier  
operating at a given supply voltage and driving a specified output load.  
PDMAX = (VDD  
)
2 / (2π2ZL)  
(2)  
Since the LM4953 has two operational amplifiers in one package, the maximum internal power dissipation point  
is twice that of the number which results from Equation 2. Even with large internal power dissipation, the LM4953  
does not require heat sinking over a large range of ambient temperatures. The maximum power dissipation point  
obtained must not be greater than the power dissipation that results from Equation 3:  
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PDMAX = (TJMAX - TA) / (θJA  
)
(3)  
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 2 is greater than  
that of Equation 3, then either the supply voltage must be decreased, the load impedance increased or TA  
reduced. 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.  
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 LM4953's  
power supply pin and ground as short as possible.  
AUTOMATIC STANDBY MODE  
The LM4953 features Automatic Standby Mode circuitry (patent pending). In the absence of an input signal, after  
approximately 3 seconds, the LM4953 goes into low current standby mode. The LM4953 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.  
To ensure correct operation of Automatic Standby Mode, proper layout techniques should be implemented.  
Separating PGND and SGND can help reduce noise entering the LM4953 in noisy environments. It is also  
important to use correct power off sequencing. The device should be in shutdown and then powered off in order  
to ensure proper functionality of the Auto-Standby feature. 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.  
MICRO POWER SHUTDOWN  
The voltage applied to the SD controls the LM4953’s shutdown function. When active, the LM4953’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 logic-high 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 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 100kpull-up resistor  
between the SD pins and VDD. Connect the switch between the SD pins and ground. Select normal amplifier  
operation by opening the switch. Closing the switch connects the SD pins to ground, activating micro-power  
shutdown. The switch and resistor ensure that the SD 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  
pins. Driving the SD pins with active circuitry eliminates the pull-up resistor.  
EXPOSED-DAP CONSIDERATIONS  
It is essential that the exposed Die Attach Paddle (DAP), for the LM4953, is NOT connected to GND. For optimal  
operation it should be connected to AVss and VCP-OUT (Pins 6 and 8).  
SELECTING PROPER EXTERNAL COMPONENTS  
Optimizing the LM4953's performance requires properly selecting external components. Though the LM4953  
operates well when using external components with wide tolerances, best performance is achieved by optimizing  
component values.  
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Charge Pump Capacitor Selection  
Use low ESR (equivalent series resistance) (<100m) 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 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.  
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.  
The LM4953 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 LM4953'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 4. Conventional headphone amplifiers require output capacitors;  
Equation 4 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.  
fi-3dB = 1 / 2πRiCi  
(4)  
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.)  
Copyright © 2005–2013, Texas Instruments Incorporated  
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Product Folder Links: LM4953 LM4953SDBD  
 
LM4953, LM4953SDBD  
SNAS299F SEPTEMBER 2005REVISED APRIL 2013  
www.ti.com  
LM4953 DEMO BOARD ARTWORK  
Figure 16. Top Layer  
Figure 17. Mid Layer 1  
Figure 18. Mid Layer 2  
Figure 19. Bottom Layer  
12  
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Copyright © 2005–2013, Texas Instruments Incorporated  
Product Folder Links: LM4953 LM4953SDBD  
 
LM4953, LM4953SDBD  
www.ti.com  
SNAS299F SEPTEMBER 2005REVISED APRIL 2013  
REVISION HISTORY  
Rev  
1.0  
Date  
Description  
2/18/05  
9/13/05  
Started D/S by copying LM4926 (DS201161).  
1.2  
Added the Typ Perf curves and Application Info  
section.  
1.3  
1.4  
1.5  
1.6  
9/14/05  
9/19/05  
Added more Typ Perf curves.  
First WEB release on the D/S.  
Fixed some typo, then re-released D/S to the  
WEB.  
11/11/05  
11/14/05  
Added the WSON boards, then re-released D/S  
to the WEB... not released on this date..  
Added the WSON boards, then re-released D/S  
to the WEB (per Nisha).  
1.7  
1.8  
11/15/05  
12/21/05  
Text edit.  
Added the EXPOSED-DAP  
CONSIDERATIONS (Application Info section),  
then re-released D/S to the WEB.  
1.9  
2/01/06  
Edited 20142168 (Typ Appl ckt)..., then re-  
released D/S to the WEB.  
Changes from Revision E (April 2013) to Revision F  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 12  
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Product Folder Links: LM4953 LM4953SDBD  
PACKAGE OPTION ADDENDUM  
www.ti.com  
5-Apr-2013  
PACKAGING INFORMATION  
Orderable Device  
LM4953SD/NOPB  
LM4953SDX/NOPB  
Status Package Type Package Pins Package  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
Top-Side Markings  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4)  
ACTIVE  
WSON  
WSON  
NHK  
14  
14  
1000  
Green (RoHS  
& no Sb/Br)  
CU SN  
CU SN  
Level-1-260C-UNLIM  
L4953  
L4953  
ACTIVE  
NHK  
4500  
Green (RoHS  
& no Sb/Br)  
Level-1-260C-UNLIM  
(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)  
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side 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 Top-Side Marking for that device.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
8-Apr-2013  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LM4953SD/NOPB  
LM4953SDX/NOPB  
WSON  
WSON  
NHK  
NHK  
14  
14  
1000  
4500  
178.0  
330.0  
12.4  
12.4  
3.3  
3.3  
4.3  
4.3  
1.0  
1.0  
8.0  
8.0  
12.0  
12.0  
Q1  
Q1  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
8-Apr-2013  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LM4953SD/NOPB  
LM4953SDX/NOPB  
WSON  
WSON  
NHK  
NHK  
14  
14  
1000  
4500  
203.0  
367.0  
190.0  
367.0  
41.0  
35.0  
Pack Materials-Page 2  
MECHANICAL DATA  
NHK0014A  
SDA14A (Rev A)  
www.ti.com  
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