LM4906MM/NOPB [TI]

具有可选增益的 1W 单声道、模拟输入 AB 类音频放大器 | DGK | 8 | -40 to 85;
LM4906MM/NOPB
型号: LM4906MM/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

具有可选增益的 1W 单声道、模拟输入 AB 类音频放大器 | DGK | 8 | -40 to 85

放大器 光电二极管 商用集成电路 音频放大器
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LM4906, LM4906LDBD, LM4906MMBD  
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SNAS191E APRIL 2003REVISED MAY 2013  
LM4906  
1W, Bypass-Capacitor-less Audio Amplifier with  
Internal Selectable Gain  
Check for Samples: LM4906, LM4906LDBD, LM4906MMBD  
1
FEATURES  
DESCRIPTION  
The LM4906 is an audio power amplifier primarily  
2
Selectable Gain of 6dB (2V/V) or 12dB (4V/V)  
designed for demanding applications in mobile  
phones and other portable communication device  
applications. It is capable of delivering 1W of  
continuous average power to an 8BTL load with  
less than 1% distortion (THD+N) from a +5V power  
supply.  
No Output or PSRR Bypass Capacitors  
Required  
Improved “Click and Pop” Suppression  
Circuitry  
Very Fast Turn on Time: 5ms (Typ)  
Minimum External Components  
2.6 - 5.5V Operation  
The LM4906 is the first Texas Instruments Boomer  
Power Amplifier that does not require an external  
PSRR bypass capacitor. The LM4906 also has an  
internal selectable gain of either 6dB or 12dB. In  
addition, no output coupling capacitors or bootstrap  
capacitors are required which makes the LM4906  
ideally suited for cell phone and other low voltage  
portable applications.  
BTL Output Can Drive Capacitive Loads  
Ultra Low Current Shutdown Mode (SD Low)  
APPLICATIONS  
Portable Computers  
Desktop Computers  
Multimedia Monitors  
The LM4906 contains advanced pop and click  
circuitry that eliminates noise, which would otherwise  
occur during turn-on and turn-off transitions.  
Boomer audio power amplifiers were designed  
specifically to provide high quality output power with a  
minimal amount of external components. The  
KEY SPECIFICATIONS  
Improved PSRR at 217Hz for +3V: 71 dB  
LM4906 features  
a
low -power consumption  
Power Output at +5V, THD+N = 1%, 8: 1.0 W  
shutdown mode (the part is enabled by pulling the SD  
pin high). Additionally, the LM4906 features an  
internal thermal shutdown protection mechanism.  
(Typ)  
Power Output at +3V, THD+N = 1%, 8: 390  
mW (Typ)  
Total Shutdown Power Supply Current: 0.1µA  
(Typ)  
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
All 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 © 2003–2013, Texas Instruments Incorporated  
LM4906, LM4906LDBD, LM4906MMBD  
SNAS191E APRIL 2003REVISED MAY 2013  
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Typical Application  
Figure 1. Typical Audio Amplifier Application Circuit  
Connection Diagram  
Figure 2. VSSOP Package (Top View)  
Figure 3. WSON Package (Top View)  
See Package Number DGK  
See Package Number NGZ  
LM4906GR Pin Designation  
Pin (Bump) Number  
Pin Function  
Shutdown  
No Connect  
VO2  
A1  
A2  
A3  
A4  
B1  
B2  
B3  
B4  
C1  
C2  
C3  
No Connect  
GND  
No Connect  
GND  
GND  
Gain Select  
IN  
No Connect  
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LM4906GR Pin Designation (continued)  
C4  
D1  
D2  
D3  
D4  
VDD  
No Connect  
No Connect  
VO1  
VDD  
Absolute Maximum Ratings(1)(2)  
Supply Voltage(3)  
6.0V  
65°C to +150°C  
0.3V to VDD +0.3V  
Internally Limited  
2000V  
Storage Temperature  
Input Voltage  
Power Dissipation(4)(5)  
ESD Susceptibility(6)  
ESD Susceptibility(7)  
200V  
Junction Temperature  
150°C  
θJC (VSSOP)  
θJA (VSSOP)  
θJC (WSON)  
θJA (WSON)  
56°C/W  
190°C/W  
Thermal Resistance  
12°C/W  
63°C/W  
(1) 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 ensured for parameters where no limit is given; however, the typical value is a good indication  
of device performance.  
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and  
specifications.  
(3) If the product is in Shutdown mode and VDD exceeds 6V (to a max of 8V 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 device will be protected. If the device is  
enabled when VDD is greater than 5.5V and less than 6.5V, no damage will occur, although operation life will be reduced. Operation  
above 6.5V with no current limit will result in permanent damage.  
(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 LM4906, see Figure 10 for additional information.  
(5) Maximum power dissipation in the device (PDMAX) occurs at an output power level significantly below full output power. PDMAX can be  
calculated using Equation 1 shown in the Application Information section. It may also be obtained from the power dissipation graphs.  
(6) Human body model, 100pF discharged through a 1.5kresistor.  
(7) Machine Model, 220pF–240pF discharged through all pins.  
Operating Ratings  
Temperature Range  
TMIN TA TMAX  
40°C TA 85°C  
2.6V VDD 5.5V  
Supply Voltage  
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Electrical Characteristics VDD = 5V(1)(2)  
The following specifications apply for the circuit shown in Figure 1, unless otherwise specified. Limits apply for TA = 25°C.  
LM4906  
Units  
(Limits)  
Symbol  
Parameter  
Conditions  
Typical(3)  
Limit(4)(5)  
VIN = 0V, Io = 0A, No Load  
VIN = 0V, Io = 0A, 8Load  
VSD = GND  
3.5  
4
7
8
mA (max)  
mA (max)  
µA (max)  
mV (max)  
IDD  
Quiescent Power Supply Current  
ISD  
Shutdown Current  
0.1  
7
2
VOS  
Output Offset Voltage  
35  
THD+N = 1% (max); f = 1 kHz  
RL = 8Ω  
Po  
Output Power  
1.0  
0.9  
W (min)  
TWU  
Wake-up time  
5
ms  
%
THD+N  
Total Harmonic Distortion+Noise  
Po = 0.4 Wrms; f = 1kHz  
0.2  
Vripple = 200mV sine p-p  
Input terminated with 10Ω  
Gain at 6dB  
67 (f = 217Hz)  
70 (f = 1kHz)  
PSRR  
Power Supply Rejection Ratio  
dB  
VSDIH  
VSDIL  
Shutdown Voltage Input High  
Shutdown Voltage Input Low  
SD Pin High = Part On  
SD Pin Low = Part Off  
1.5  
1.3  
V (min)  
V (max)  
(1) All voltages are measured with respect to the ground 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 which 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) Typicals are measured at 25°C and represent the parametric norm.  
(4) Datasheet min/max specification limits are specified by design, test, or statistical analysis.  
(5) Limits are specified to AOQL (Average Outgoing Quality Level).  
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Electrical Characteristics VDD = 3V(1)(2)  
The following specifications apply for the circuit shown in Figure 1, unless otherwise specified. Limits apply for TA = 25°C.  
LM4906  
Limit(4)(5)  
Units  
(Limits)  
Symbol  
Parameter  
Conditions  
Typical(3)  
VIN = 0V, Io = 0A, No Load  
VIN = 0V, Io = 0A, 8Load  
VSD = GND  
2.6  
3
6
7
mA (max)  
mA (max)  
µA (max)  
mV (max)  
IDD  
Quiescent Power Supply Current  
ISD  
Shutdown Current  
0.1  
7
2
VOS  
Output Offset Voltage  
35  
THD+N = 1% (max); f = 1 kHz  
RL = 8Ω  
Po  
Output Power  
390  
mW  
TWU  
Wake-up time  
4
ms  
%
THD+N  
Total Harmonic Distortion+Noise  
Po = 0.15 Wrms; f = 1kHz  
0.1  
Vripple = 200mV sine p-p  
Input terminated with 10Ω  
Gain at 6dB  
71 (f = 217Hz)  
73 (f = 1kHz)  
PSRR  
Power Supply Rejection Ratio  
dB  
VSDIH  
VSDIL  
Shutdown Voltage Input High  
Shutdown Voltage Input Low  
SD Pin High = Part On  
SD Pin Low = Part Off  
1.1  
0.9  
V (min)  
V (max)  
(1) 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 ensured for parameters where no limit is given; however, the typical value is a good indication  
of device performance.  
(2) All voltages are measured with respect to the ground pin, unless otherwise specified.  
(3) Typicals are measured at 25°C and represent the parametric norm.  
(4) Limits are specified to AOQL (Average Outgoing Quality Level).  
(5) Datasheet min/max specification limits are specified by design, test, or statistical analysis.  
External Components Description  
Components  
Functional Description  
1.  
C2  
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a highpass filter with  
Ri at fc = 1 / (2πRiCi). Refer to the section, AUDIO POWER AMPLIFIER DESIGN, for an explanation of how to  
determine the value of Ci.  
2.  
C1  
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.  
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Typical Performance Characteristics  
THD+N vs Frequency  
VDD = 5V, RL = 8,  
f = 1kHz, PWR = 500mW  
THD+N vs Frequency  
VDD = 3V, RL = 8,  
f = 1kHz, PWR = 250mW  
Figure 4.  
Figure 5.  
THD+N vs Power Out  
VDD = 5V, RL = 8, f = 1kHz  
THD+N vs Power Out  
VDD = 3V, RL = 8, f = 1kHz  
Figure 6.  
Figure 7.  
Power Supply Rejection Ratio  
vs Frequency  
Power Supply Rejection Ratio  
vs Frequency  
VDD = 5V, RL = 8Ω  
VDD = 3V, RL = 8Ω  
Figure 8.  
Figure 9.  
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Typical Performance Characteristics (continued)  
Noise Floor  
VDD = 5V, RL = 8Ω  
80kHz Bandwith, Input to GND  
Power Derating Curve  
Figure 10.  
Figure 11.  
Power Dissipation  
vs Output Power, VDD = 3V, RL = 8Ω  
Power Dissipation  
vs Output Power, VDD = 5V, RL = 8Ω  
0.7  
0.25  
0.6  
0.5  
0.4  
0.3  
0.2  
0.1  
0.0  
0.20  
0.15  
0.10  
0.05  
0.00  
0.0  
0.2  
0.4  
0.6  
0.8  
1.0  
1.2  
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40  
OUTPUT POWER (W)  
OUTPUT POWER (W)  
Figure 12.  
Figure 13.  
Shutdown Hysteresis Voltage  
VDD = 5V, SD Mode = VDD (High)  
Shutdown Hysteresis Voltage  
VDD = 5V, SD Mode = VDD (Low)  
4.5  
4.0  
3.5  
3.0  
2.5  
2.0  
1.5  
1.0  
0.5  
0.0  
4.5  
4.0  
3.5  
3.0  
2.5  
2.0  
1.5  
1.0  
0.5  
0.0  
0.0  
1.0  
2.0  
3.0  
4.0  
0.0  
1.0  
2.0  
3.0  
4.0  
SHUTDOWN VOLTAGE (V)  
SHUTDOWN VOLTAGE (V)  
Figure 14.  
Figure 15.  
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Typical Performance Characteristics (continued)  
Shutdown Hysteresis Voltage  
VDD = 3V, SD Mode = VDD (High)  
Shutdown Hysteresis Voltage  
VDD = 3V, SD Mode = GND (Low)  
3.5  
3.0  
2.5  
2.0  
1.5  
1.0  
0.5  
0.0  
0.0  
1.0  
2.0  
3.0  
4.0  
SHUTDOWN VOLTAGE (V)  
Figure 16.  
Figure 17.  
Output Power vs Supply Voltage, RL = 8Ω  
Output Power vs Supply Voltage, RL = 32Ω  
600.0  
2000  
1800  
1600  
500.0  
1400  
400.0  
THD+N = 10%  
1200  
THD+N = 10%  
300.0  
1000  
800  
200.0  
600  
THD+N = 1%  
400  
100.0  
THD+N = 1%  
200  
0.0  
1.5  
0
2.5  
3.5  
4.5  
5.5  
2
3
4
5
6
SUPPLY VOLTAGE (V)  
SUPPLY VOLTAGE (V)  
Figure 18.  
Figure 19.  
Output Power vs Supply Voltage, RL = 16Ω  
Frequency Response vs Input Capacitor Size  
1200  
7
1000  
800  
0.39mF  
6
5
4
THD+N = 10%  
600  
3
400  
1mF  
THD+N = 1%  
2
1
0
200  
0
1.5  
3.0  
4.5  
6.0  
20  
200  
2k  
20k  
SUPPLY VOLTAGE (V)  
FREQUENCY (Hz)  
Figure 20.  
Figure 21.  
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Typical Performance Characteristics (continued)  
PSRR Distribution  
VDD = 5V, f = 1kHz, RL = 8Ω  
PSRR Distribution  
VDD = 5V, f = 217Hz, RL = 8Ω  
-80  
-70  
-60  
-75  
-68  
-61  
(dBr)  
(dBr)  
Figure 22.  
Figure 23.  
PSRR Distribution  
VDD = 3V, f = 1kHz, RL = 8Ω  
PSRR Distribution  
VDD = 3V, f = 217Hz, RL = 8Ω  
-85  
-74  
-62  
-80  
-72  
-63  
(dBr)  
(dBr)  
Figure 24.  
Figure 25.  
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APPLICATION INFORMATION  
BRIDGE CONFIGURATION EXPLANATION  
As shown in Figure 26, the LM4906 has two internal operational amplifiers. The first amplifier's gain is either 6dB  
or 12dB depending on the gain select input (Low = 6dB, High = 12dB). The second amplifier's gain is fixed by the  
two internal 20kresistors. Figure 26 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 by 180°. Consequently,  
the differential gain for the IC is  
AVD = 2 * (20k / 20k) or 2 * (40k / 20k)  
(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 the 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 closed-  
loop gain without causing excessive clipping, please refer to the Audio Power Amplifier Design section.  
A bridge configuration, such as the one used in LM4906, 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, 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.  
POWER DISSIPATION  
Power dissipation is a major concern when designing a successful amplifier, whether the amplifier is bridged or  
single-ended. A direct consequence of the increased power delivered to the load by a bridge amplifier is an  
increase in internal power dissipation. Since the LM4906 has two operational amplifiers in one package, the  
maximum internal power dissipation is 4 times that of a single-ended amplifier. The maximum power dissipation  
for a given application can be derived from the power dissipation graphs or from Equation 2.  
PDMAX = 4 * (VDD)2 / (2π2RL)  
(2)  
It is critical that the maximum junction temperature TJMAX of 150°C is not exceeded. TJMAX can be determined  
from the power derating curves by using PDMAX and the PC board foil area. By adding copper foil, the thermal  
resistance of the application can be reduced from the free air value of θJA, resulting in higher PDMAX values  
without thermal shutdown protection circuitry being activated. Additional copper foil can be added to any of the  
leads connected to the LM4906. It is especially effective when connected to VDD, GND, and the output pins.  
Refer to the Application Information on the LM4906 reference design board for an example of good heat sinking.  
If TJMAX still exceeds 150°C, then additional changes must be made. These changes can include reduced supply  
voltage, higher load impedance, or reduced ambient temperature. Internal power dissipation is a function of  
output power. Refer to the Typical Performance Characteristics curves for power dissipation information for  
different output powers and output loading.  
POWER SUPPLY BYPASSING  
As with any amplifier, proper supply bypassing is critical for low noise performance and high power supply  
rejection. The capacitor location on the power supply pin should be as close to the device as possible. Typical  
applications employ a 5V regulator with 10µF tantalum 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 LM4906.  
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TURNING ON THE LM4906  
The power supply must first be applied before the application of an input signal to the device and the ramp time  
to VDD must be less than 4ms, otherwise the wake-up time of the device will be affected. After applying VDD, the  
LM4906 will turn-on after an initial minimum threshold input signal of 7mVRMS, resulting in a generated output  
differential signal. An input signal of less than 7mVRMS will result in a negligible output voltage. Once the device  
is turned on, the input signal can go below the 7mVRMS without shutting the device off. If, however, SHUTDOWN  
or VDD is cycled, the minimum threshold requirement for the input signal must first be met again, with VDD  
ramping first.  
SHUTDOWN FUNCTION  
In order to reduce power consumption while not in use, the LM4906 contains shutdown circuitry that is used to  
turn off the amplifier's bias circuitry. The device is placed into shutdown mode by toggling the Shutdown pin  
Low/ground. The trigger point for shutdown low is shown as a typical value in the Supply Current vs Shutdown  
Voltage graphs in the Typical Performance Characteristics section. It is best to switch between ground and  
supply for maximum performance. While the device may be disabled with shutdown voltages in between ground  
and supply, the idle current may be greater than the typical value of 0.1µA. 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 to shutdown. Another solution is to use a single-throw switch in conjunction  
with an external pull-up resistor (or pull-down, depending on shutdown high or low application). This scheme  
ensures that the shutdown pin will not float, thus preventing unwanted state changes.  
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 100Hz to  
150Hz. Thus, using a large input capacitor may not increase actual system performance.  
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  
1/2 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.  
AUDIO POWER AMPLIFIER DESIGN  
A 1W/8Audio Amplifier  
Power Output  
Load Impedance  
Input Level  
1 Wrms  
8Ω  
1 Vrms  
Given:  
Input Impedance  
Bandwidth  
20 kΩ  
100 Hz–20 kHz ± 0.25 dB  
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 Performance Characteristics section, the supply  
rail can be easily found.  
Extra supply voltage creates headroom that allows the LM4906 to reproduce peaks in excess of 1W 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 the Power Dissipation section.  
The gain of the LM4906 is internally set at either 6dB or 12dB.  
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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 specified.  
fL = 100Hz / 5 = 20Hz  
fH = 20kHz * 5 = 100kHz  
As stated in the External Components Description section, Rin (20k) in conjunction with C2 create a highpass  
filter.  
C2 1 / (2π*20k*20Hz) = 0.397µF; use 0.39µF  
Figure 26. REFERENCE DESIGN BOARD SCHEMATIC  
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Product Folder Links: LM4906 LM4906LDBD LM4906MMBD  
LM4906, LM4906LDBD, LM4906MMBD  
www.ti.com  
SNAS191E APRIL 2003REVISED MAY 2013  
LM4906 VSSOP DEMO BOARD ARTWORK  
Figure 27. Top Layer  
Figure 28. Bottom Layer  
Copyright © 2003–2013, Texas Instruments Incorporated  
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LM4906, LM4906LDBD, LM4906MMBD  
SNAS191E APRIL 2003REVISED MAY 2013  
www.ti.com  
LM4906 LD DEMO BOARD ARTWORK  
Figure 29. Top Layer  
Figure 30. Bottom Layer  
14  
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Product Folder Links: LM4906 LM4906LDBD LM4906MMBD  
LM4906, LM4906LDBD, LM4906MMBD  
www.ti.com  
SNAS191E APRIL 2003REVISED MAY 2013  
Table 1. Mono LM4906 Reference Design Boards  
Bill of Material  
Part Description  
Quantity  
Reference Designator  
LM4906 Audio Amplifier  
1
1
1
5
U1  
Tantalum Capcitor, 1µF  
C1  
Ceramic Capacitor, 0.39µF  
C2  
Jumper Header Vertical Mount 2X1 0.100“ spacing  
J1, J2, Input, Output, VDD  
PCB LAYOUT GUIDELINES  
This section provides practical guidelines for mixed signal PCB layout that involves various digital/analog power  
and ground traces. Designers should note that these are only "rule-of-thumb" recommendations and the actual  
results will depend heavily on the final layout.  
GENERAL MIXED SIGNAL LAYOUT RECOMMENDATION  
Power and Ground Circuits  
For 2 layer mixed signal design, it is important to isolate the digital power and ground trace paths from the  
analog power and ground trace paths. Star trace routing techniques (bringing individual traces back to a central  
point rather than daisy chaining traces together in a serial manner) can have a major impact on low level signal  
performance. Star trace routing refers to using individual traces to feed power and ground to each circuit or even  
device. This technique will require a greater amount of design time but will not increase the final price of the  
board. The only extra parts required will be some jumpers.  
Single-Point Power / Ground Connections  
The analog power traces should be connected to the digital traces through a single point (link). A "Pi-filter" can  
be helpful in minimizing High Frequency noise coupling between the analog and digital sections. It is further  
recommended to put digital and analog power traces over the corresponding digital and analog ground traces to  
minimize noise coupling.  
Placement of Digital and Analog Components  
All digital components and high-speed digital signal traces should be located as far away as possible from analog  
components and circuit traces.  
Avoiding Typical Design / Layout Problems  
Avoid ground loops or running digital and analog traces parallel to each other (side-by-side) on the same PCB  
layer. When traces must cross over each other do it at 90 degrees. Running digital and analog traces at 90  
degrees to each other from the top to the bottom side as much as possible will minimize capacitive noise  
coupling and cross talk.  
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SNAS191E APRIL 2003REVISED MAY 2013  
www.ti.com  
REVISION HISTORY  
Changes from Revision D (May 2013) to Revision E  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 15  
16  
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PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LM4906MM/NOPB  
ACTIVE  
VSSOP  
DGK  
8
1000 RoHS & Green  
SN  
Level-1-260C-UNLIM  
-40 to 85  
GA8  
(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 <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
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  
29-Oct-2021  
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)  
LM4906MM/NOPB  
VSSOP  
DGK  
8
1000  
178.0  
12.4  
5.3  
3.4  
1.4  
8.0  
12.0  
Q1  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
29-Oct-2021  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
VSSOP DGK  
SPQ  
Length (mm) Width (mm) Height (mm)  
208.0 191.0 35.0  
LM4906MM/NOPB  
8
1000  
Pack Materials-Page 2  
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AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, regulatory or other requirements.  
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