LM4674ATL/NOPB [TI]

免滤波 2.5 立体声 D 类音频功率放大器 | YZR | 16 | -40 to 85;
LM4674ATL/NOPB
型号: LM4674ATL/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
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免滤波 2.5 立体声 D 类音频功率放大器 | YZR | 16 | -40 to 85

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LM4674A  
www.ti.com  
SNAS366A SEPTEMBER 2006REVISED MAY 2013  
LM4674A  
Filterless 2.5W Stereo Class D Audio Power  
Amplifier  
Check for Samples: LM4674A  
1
FEATURES  
DESCRIPTION  
The LM4674A is a single supply, high efficiency,  
2.5W/channel, filterless switching audio amplifier. A  
low noise PWM architecture eliminates the output  
filter, reducing external component count, board area  
consumption, system cost, and simplifying design.  
2
Output Short Circuit Protection  
Stereo Class D Operation  
No Output Filter Required  
Logic Selectable Gain  
Independent Shutdown Control  
Minimum External Components  
Click and Pop Suppression  
Micro-Power Shutdown  
The LM4674A is designed to meet the demands of  
mobile phones and other portable communication  
devices. Operating from a single 5V supply, the  
device is capable of delivering 2.5W/channel of  
continuous output power to a 4load with less than  
10% THD+N. Flexible power supply requirements  
allow operation from 2.4V to 5.5V.  
Available in Space-Saving 2mm x 2mm x  
0.6mm DSBGA Package  
The LM4674A features high efficiency compared to  
conventional Class AB amplifiers. When driving an  
8speaker from a 3.6V supply, the device features  
85% efficiency at PO = 500mW. Four gain options are  
pin selectable through the GAIN0 and GAIN1 pins.  
APPLICATIONS  
Mobile Phones  
PDAs  
Laptops  
Output short circuit protection prevents the device  
from being damaged during fault conditions. Superior  
click and pop suppression eliminates audible  
transients on power-up/down and during shutdown.  
Independent left/right shutdown controls maximizes  
power savings in mixed mono/stereo applications.  
KEY SPECIFICATIONS  
Efficiency at 3.6V, 100mW into 880% (typ)  
Efficiency at 3.6V, 500mW into 885% (typ)  
Efficiency at 5V, 1W into 885% (typ)  
Quiescent Power Supply Current at 3.6V  
Supply 4mA  
Power Output at VDD = 5V, RL = 4, THD 10%  
2.5W (typ)  
Power Output at VDD = 5V, RL = 8, THD 10%  
1.5W (typ)  
Shutdown 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 © 2006–2013, Texas Instruments Incorporated  
LM4674A  
SNAS366A SEPTEMBER 2006REVISED MAY 2013  
www.ti.com  
Typical Application  
2.4V to 5.5V  
PV  
V
DD  
DD  
INR-  
OUTRA  
OUTRB  
INR+  
OUTLA  
OUTLB  
INL-  
INL+  
LM4674A  
/SDR  
/SDL  
SHUTDOWN  
CONTROL  
GAIN0  
GAIN1  
GAIN  
CONTROL  
GND  
PGND  
Figure 1. Typical Audio Amplifier Application Circuit  
Connection Diagram  
OUTLB  
OUTLA  
/SDL  
/SDR  
G1  
PGND  
GND  
G0  
OUTRB  
OUTRA  
4
3
2
PV  
DD  
V
DD  
INL+  
INL-  
INR-  
INR+  
1
A
B
C
D
Figure 2. DSBGA - Top View  
See YZR0016 Package  
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LM4674A  
www.ti.com  
SNAS366A SEPTEMBER 2006REVISED MAY 2013  
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(1)  
6.0V  
65°C to +150°C  
–0.3V to VDD +0.3V  
Internally Limited  
2000V  
Storage Temperature  
Input Voltage  
Power Dissipation(4)  
ESD Susceptibility, all other pins(5)  
ESD Susceptibility(6)  
200V  
Junction Temperature (TJMAX  
)
150°C  
Thermal Resistance  
θJA  
45.7°C/W  
(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) If Military/Aerospace specified devices are required, please contact the TI 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 LM4674A see power derating currents for more information.  
(5) Human body model, 100pF discharged through a 1.5kresistor.  
(6) Machine Model, 220pF–240pF discharged through all pins.  
Operating Ratings(1)(2)  
Temperature Range TMIN TA TMAX  
40°C TA 85°C  
2.4V VDD 5.5V  
Supply Voltage  
(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.  
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LM4674A  
SNAS366A SEPTEMBER 2006REVISED MAY 2013  
www.ti.com  
Electrical Characteristics VDD = 3.6V(1)(2)  
The following specifications apply for AV = 6dB, RL = 15µH + 8+ 15µH, f = 1kHz unless otherwise specified. Limits apply for  
TA = 25°C.  
LM4674A  
Units  
(Limits)  
Symbol  
VOS  
Parameter  
Conditions  
Typical(3)  
Limit(4)  
Differential Output Offset Voltage  
VIN = 0, VDD = 2.4V to 5.0 V  
VIN = 0, RL = ,  
5
mV  
mA  
4
6
Both channels active, VDD = 3.6V  
VIN = 0, RL = ,  
IDD  
Quiescent Power Supply Current  
mA  
5
7.5  
Both channels active, VDD = 5V  
VSD1 = VSD2 = GND  
ISD  
Shutdown Current  
0.03  
1
μA  
V (min)  
V (max)  
ms  
VSDIH  
VSDIL  
TWU  
Shutdown Voltage Input High  
Shutdown Voltage Input Low  
Wake Up Time  
1.4  
0.4  
VSHUTDOWN = 0.4V  
GAIN0, GAIN1 = GND  
GAIN0 = VDD, GAIN1 = GND  
GAIN0 = GND, GAIN1 = VDD  
GAIN0, GAIN1 = VDD  
AV = 6dB  
4.2  
6
6 ± 0.5  
12 ± 0.5  
18 ± 0.5  
24 ± 0.5  
dB  
12  
dB  
AV  
Gain  
18  
dB  
24  
dB  
28  
kΩ  
AV = 12dB  
18.75  
11.25  
6.25  
kΩ  
RIN  
Input Resistance  
AV = 18dB  
kΩ  
AV = 24dB  
kΩ  
RL = 15μH + 4+ 15μH, THD = 10%  
f = 1kHz, 22kHz BW  
VDD = 5V  
2.5  
1.2  
W
W
W
VDD = 3.6V  
VDD = 2.5V  
0.530  
RL = 15μH + 8+ 15μH, THD = 10%  
f = 1kHz, 22kHz BW  
VDD = 5V  
1.5  
0.78  
0.350  
W
W
W
VDD = 3.6V  
0.6  
VDD = 2.5V  
PO  
Output Power  
RL = 15μH + 4+ 15μH, THD = 1%  
f = 1kHz, 22kHz BW  
VDD = 5V  
1.9  
1
W
W
W
VDD = 3.6V  
VDD = 2.5V  
0.430  
RL = 15μH + 8+ 15μH, THD = 1%  
f = 1kHz, 22kHz BW  
VDD = 5V  
1.25  
0.63  
0.285  
0.07  
0.05  
W
W
W
%
%
VDD = 3.6V  
VDD = 2.5V  
PO = 500mW, f = 1kHz, RL = 8Ω  
PO = 300mW, f = 1kHz, RL = 8Ω  
THD+N  
Total Harmonic Distortion  
(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) Limits are specified to TI's AOQL (Average Outgoing Quality Level).  
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Electrical Characteristics VDD = 3.6V(1)(2) (continued)  
The following specifications apply for AV = 6dB, RL = 15µH + 8+ 15µH, f = 1kHz unless otherwise specified. Limits apply for  
TA = 25°C.  
LM4674A  
Typical(3) Limit(4)  
Units  
(Limits)  
Symbol  
Parameter  
Conditions  
VRIPPLE = 200mVP-P Sine,  
fRipple = 217Hz, Inputs AC GND,  
CI = 1μF, input referred  
VRIPPLE = 1VP-P Sine,  
fRipple = 1kHz, Inputs AC GND,  
CI = 1μF, input referred  
VRIPPLE = 1VP-P  
75  
75  
dB  
dB  
PSRR  
Power Supply Rejection Ratio  
CMRR  
Common Mode Rejection Ratio  
Efficiency  
67  
85  
dB  
%
fRIPPLE = 217Hz  
PO = 1W, f = 1kHz,  
η
RL = 8, VDD = 5V  
Crosstalk  
PO = 500mW, f = 1kHz  
VDD = 5V, PO = 1W  
84  
96  
20  
dB  
dB  
μV  
SNR  
Signal to Noise Ratio  
Output Noise  
εOS  
Input referred, A-Weighted Filter  
External Components Description  
(Figure 1)  
Components  
Functional Description  
1.  
CS  
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.  
2.  
CI  
Input AC coupling capacitor which blocks the DC voltage at the amplifier's input terminals.  
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Block Diagrams  
2.4V to 5.5V  
0.1 mF  
1 mF  
PV  
V
DD  
DD  
1 mF  
OUTRA  
OUTRB  
INR-  
GAIN/  
MODULATOR  
H-BRIDGE  
1 mF  
INR+  
/SDR  
GAIN0  
OSCILLATOR  
GAIN1  
/SDL  
1 mF  
OUTLA  
OUTLB  
INL-  
GAIN/  
MODULATOR  
H-BRIDGE  
1 mF  
INL+  
GND  
PGND  
PV  
DD  
V
DD  
OSCILLATOR  
INL+  
INL-  
OUTLA  
OUTLB  
PWM MODULATOR  
H-BRIDGE  
G0  
GAIN  
CONTROL  
CLICK/POP  
SUPPRESSION  
BIAS  
G1  
OUTRA  
OUTRB  
INR+  
INR-  
PWM MODULATOR  
H-BRIDGE  
PGND  
GND /SDR  
/SDL  
Figure 3. Differential Input Configuration  
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Typical Performance Characteristics  
THD+N vs Output Power  
f = 1kHz, AV = 24dB, RL = 8  
THD+N vs Output Power  
f = 1kHz, AV = 6dB, RL = 8Ω  
100  
10  
100  
10  
V
DD  
= 5V  
V
= 5V  
DD  
V
= 3.6V  
V
DD  
= 3.6V  
DD  
1
1
V
= 2.5V  
V
= 2.5V  
DD  
DD  
0.1  
0.1  
0.01  
0.01  
0.001  
0.01  
0.1  
1
10  
0.001  
0.01  
0.1  
1
10  
OUTPUT POWER (W)  
OUTPUT POWER (W)  
Figure 4.  
Figure 5.  
THD+N vs Output Power  
f= 1kHz, AV = 24dB, RL = 4Ω  
THD+N vs Output Power  
f = 1kHz, AV = 6dB, RL = 4Ω  
100  
10  
100  
10  
V
= 5V  
V
= 5V  
DD  
DD  
V
DD  
= 3.6V  
V
= 3.6V  
DD  
1
1
V
= 2.5V  
V
= 2.5V  
DD  
DD  
0.1  
0.1  
0.01  
0.01  
0.001  
0.01  
0.1  
1
10  
0.001  
0.01  
0.1  
1
10  
OUTPUT POWER (W)  
OUTPUT POWER (W)  
Figure 6.  
Figure 7.  
THD+N vs Frequency  
VDD = 2.5V, POUT = 100mW, RL = 8Ω  
THD+N vs Frequency  
VDD = 3.6V, POUT = 250mW, RL = 8Ω  
100  
100  
10  
1
10  
1
0.1  
0.01  
0.1  
0.01  
0.001  
0.001  
10  
100  
1000  
10000  
100000  
10  
100  
1000  
10000  
100000  
FREQUENCY (W)  
FREQUENCY (W)  
Figure 8.  
Figure 9.  
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Typical Performance Characteristics (continued)  
THD+N vs Frequency  
VDD = 5V, POUT = 375mW, RL = 8Ω  
THD+N vs Frequency  
VDD = 2. 5V, POUT = 100mW, RL = 4Ω  
100  
10  
100  
10  
1
1
0.1  
0.1  
0.01  
0.01  
0.001  
0.001  
10  
100  
1000  
10000  
100000  
10  
100  
1000  
10000  
100000  
FREQUENCY (W)  
FREQUENCY (W)  
Figure 10.  
Figure 11.  
THD+N vs Frequency  
VDD = 3.6V, POUT = 250mW, RL = 4Ω  
THD+N vs Frequency  
VDD = 5V, POUT = 375mW, RL = 4Ω  
100  
100  
10  
10  
1
1
0.1  
0.01  
0.1  
0.01  
0.001  
0.001  
10  
100  
1000  
10000  
100000  
10  
100  
1000  
10000  
100000  
FREQUENCY (W)  
FREQUENCY (W)  
Figure 12.  
Figure 13.  
Efficiency vs. Output Power  
Efficiency vs. Output Power  
RL = 4, f = 1kHz  
RL = 8, f = 1kHz  
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
V
= 5V  
DD  
V
= 5V  
DD  
V
= 3.6V  
DD  
V
= 3.6V  
DD  
V
= 2.5V  
DD  
V
= 2.5V  
DD  
0
500  
1000  
1500  
2000  
0
200  
400  
600  
800 1000 1200  
OUTPUT POWER (mW)  
OUTPUT POWER (mW)  
Figure 14.  
Figure 15.  
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Typical Performance Characteristics (continued)  
Power Dissipation vs. Output Power  
Power Dissipation vs. Output Power  
RL = 4, f = 1kHz  
RL = 8, f = 1kHz  
1000  
750  
500  
250  
0
400  
300  
200  
100  
0
V
= 5V  
DD  
V
= 5V  
DD  
V
= 3.6V  
DD  
V
= 3.6V  
DD  
V
= 2.5V  
V
= 2.5V  
DD  
DD  
P
= P  
+ P  
P
= P  
+ P  
OUTL OUTR  
OUT  
OUTL  
OUTR  
OUT  
0
1000  
2000  
3000  
4000  
0
500  
1000  
1500  
2000  
2500  
OUTPUT POWER (mW)  
OUTPUT POWER (mW)  
Figure 16.  
Figure 17.  
Output Power vs. Supply Voltage  
Output Power vs. Supply Voltage  
RL = 4, f = 1kHz  
RL = 8, f = 1kHz  
3000  
2500  
2000  
1500  
1000  
500  
2000  
1500  
1000  
THD+N = 10%  
THD+N = 1%  
THD+N = 10%  
THD+N = 1%  
500  
0
0
2.5  
3
3.5  
4
4.5  
5
5.5  
2.5  
3
3.5  
4
4.5  
5
5.5  
SUPPLY VOLTAGE (V)  
SUPPLY VOLTAGE (V)  
Figure 18.  
Figure 19.  
PSRR vs. Frequency  
VDD = 3.6V, VRIPPLE= 200mVP-P, RL = 8Ω  
Crosstalk vs. Frequency  
VDD = 3.6V, VRIPPLE = 1VP-P, RL = 8Ω  
0
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
-100  
0
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
10  
100  
1000  
10000  
100000  
10  
100  
1000  
10000  
100000  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 20.  
Figure 21.  
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Typical Performance Characteristics (continued)  
CMRR vs. Frequency  
VDD = 3.6V, VCM = 1VP-P, RL = 8Ω  
Supply Current vs. Supply Voltage  
No Load  
0
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
8
7
6
5
4
3
2
1
0
2.5  
3
3.5  
4
4.5  
5
5.5  
10  
100  
1000  
10000  
100000  
FREQUENCY (Hz)  
SUPPLY VOLTAGE (V)  
Figure 22.  
Figure 23.  
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APPLICATION INFORMATION  
GENERAL AMPLIFIER FUNCTION  
The LM4674A stereo Class D audio power amplifier features a filterless modulation scheme that reduces  
external component count, conserving board space and reducing system cost. The outputs of the device  
transition from VDD to GND with a 300kHz switching frequency. With no signal applied, the outputs (OUT_A and  
OUT_B) switch with a 50% duty cycle, in phase, causing the two outputs to cancel. This cancellation results in no  
net voltage across the speaker, thus there is no current to the load in the idle state.  
With the input signal applied, the duty cycle (pulse width) of the LM4674A outputs changes. For increasing output  
voltage, the duty cycle of OUT_A increases, while the duty cycle of OUT_B decreases. For decreasing output  
voltages, the converse occurs. The difference between the two pulse widths yields the differential output voltage.  
DIFFERENTIAL AMPLIFIER EXPLANATION  
As logic supplies continue to shrink, system designers are increasingly turning to differential analog signal  
handling to preserve signal to noise ratios with restricted voltage signs. The LM4674A features two fully  
differential amplifiers. A differential amplifier amplifies the difference between the two input signals. Traditional  
audio power amplifiers have typically offered only single-ended inputs resulting in a 6dB reduction of SNR  
relative to differential inputs. The LM4674A also offers the possibility of DC input coupling which eliminates the  
input coupling capacitors. A major benefit of the fully differential amplifier is the improved common mode  
rejection ratio (CMRR) over single ended input amplifiers. The increased CMRR of the differential amplifier  
reduces sensitivity to ground offset related noise injection, especially important in noisy systems.  
POWER DISSIPATION AND EFFICIENCY  
The major benefit of a Class D amplifier is increased efficiency versus a Class AB. The efficiency of the  
LM4674A is attributed to the region of operation of the transistors in the output stage. The Class D output stage  
acts as current steering switches, consuming negligible amounts of power compared to their Class AB  
counterparts. Most of the power loss associated with the output stage is due to the IR loss of the MOSFET on-  
resistance, along with switching losses due to gate charge.  
SHUTDOWN FUNCTION  
The LM4674A features independent left and right channel shutdown controls, allowing each channel to be  
disabled independently. /SDR controls the right channel, while /SDL controls the left channel. Driving either low  
disables the corresponding channel, reducing supply current to 0.03µA.  
It is best to switch between ground and VDD for minimum current consumption while in shutdown. The LM4674A  
may be disabled with shutdown voltages in between GND and VDD, the idle current will be greater than the  
typical 0.03µA value. Increased THD+N may also be observed when a voltage of less than VDD is applied to  
/SD_ for logic levels between GND and VDD Bypass /SD_ with a 0.1μF capacitor.  
The LM4674A shutdown inputs have internal pulldown resistors. The purpose of these resistors is to eliminate  
any unwanted state changes when /SD_ is floating. To minimize shutdown current, /SD_ should be driven to  
GND or left floating. If /SD_ is not driven to GND or floating, an increase in shutdown supply current will be  
noticed.  
SINGLE-ENDED AUDIO AMPLIFIER CONFIGURATION  
The LM4674A is compatible with single-ended sources. When configured for single-ended inputs, input  
capacitors must be used to block and DC component at the input of the device. Figure 25 shows the typical  
single-ended applications circuit.  
AUDIO AMPLIFIER POWER SUPPLY BYPASSING/FILTERING  
Proper power supply bypassing is critical for low noise performance and high PSRR. Place the supply bypass  
capacitor as close to the device as possible. Typical applications employ a voltage regulator with 10µF and 0.1µF  
bypass capacitors that increase supply stability. These capacitors do not eliminate the need for bypassing of the  
LM4674A supply pins. A 1µF capacitor is recommended.  
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SNAS366A SEPTEMBER 2006REVISED MAY 2013  
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AUDIO AMPLIFIER INPUT CAPACITOR SELECTION  
Input capacitors may be required for some applications, or when the audio source is single-ended. Input  
capacitors block the DC component of the audio signal, eliminating any conflict between the DC component of  
the audio source and the bias voltage of the LM4674A. The input capacitors create a high-pass filter with the  
input resistors RI. The -3dB point of the high pass filter is found using Equation 1 below.  
f = 1 / 2πRINCIN  
(1)  
The values for RI can be found in the EC table for each gain setting.  
The input capacitors can also be used to remove low frequency content from the audio signal. Small speakers  
cannot reproduce, and may even be damaged by low frequencies. High pass filtering the audio signal helps  
protect the speakers. When the LM4674A is using a single-ended source, power supply noise on the ground is  
seen as an input signal. Setting the high-pass filter point above the power supply noise frequencies, 217Hz in a  
GSM phone, for example, filters out the noise such that it is not amplified and heard on the output. Capacitors  
with a tolerance of 10% or better are recommended for impedance matching and improved CMRR and PSRR.  
AUDIO AMPLIFIER GAIN SETTING  
The LM4674A features four internally configured gain settings. The device gain is selected through the two logic  
inputs, G0 and G1. The gain settings are as shown in the following table.  
G1  
G0  
GAIN  
V/V  
2
dB  
6
0
0
1
1
0
1
0
1
4
12  
18  
24  
8
16  
PCB LAYOUT GUIDELINES  
As output power increases, interconnect resistance (PCB traces and wires) between the amplifier, load and  
power supply create a voltage drop. The voltage loss due to the traces between the LM4674A and the load  
results in lower output power and decreased efficiency. Higher trace resistance between the supply and the  
LM4674A has the same effect as a poorly regulated supply, increasing ripple on the supply line, and reducing  
peak output power. The effects of residual trace resistance increases as output current increases due to higher  
output power, decreased load impedance or both. To maintain the highest output voltage swing and  
corresponding peak output power, the PCB traces that connect the output pins to the load and the supply pins to  
the power supply should be as wide as possible to minimize trace resistance.  
The use of power and ground planes will give the best THD+N performance. In addition to reducing trace  
resistance, the use of power planes creates parasitic capacitors that help to filter the power supply line.  
The inductive nature of the transducer load can also result in overshoot on one of both edges, clamped by the  
parasitic diodes to GND and VDD in each case. From an EMI standpoint, this is an aggressive waveform that  
can radiate or conduct to other components in the system and cause interference. In is essential to keep the  
power and output traces short and well shielded if possible. Use of ground planes beads and micros-strip layout  
techniques are all useful in preventing unwanted interference.  
As the distance from the LM4674A and the speaker increases, the amount of EMI radiation increases due to the  
output wires or traces acting as antennas become more efficient with length. Ferrite chip inductors places close  
to the LM4674A outputs may be needed to reduce EMI radiation.  
12  
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SNAS366A SEPTEMBER 2006REVISED MAY 2013  
PV  
DD  
V
DD  
OSCILLATOR  
INL+  
INL-  
OUTLA  
PWM MODULATOR  
H-BRIDGE  
OUTLB  
G0  
G1  
GAIN  
CONTROL  
CLICK/POP  
SUPPRESSION  
BIAS  
OUTRA  
INR+  
INR-  
OUTRB  
PWM MODULATOR  
H-BRIDGE  
PGND  
GND /SDR  
/SDL  
Figure 24. Differential Input Configuration  
PV  
DD  
V
DD  
OSCILLATOR  
INL+  
INL-  
OUTLA  
OUTLB  
PWM MODULATOR  
H-BRIDGE  
G0  
G1  
GAIN  
CONTROL  
CLICK/POP  
SUPPRESSION  
BIAS  
OUTRA  
OUTRB  
INR+  
INR-  
PWM MODULATOR  
H-BRIDGE  
PGND  
GND /SDR  
/SDL  
Figure 25. Single-Ended Input Configuration  
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SNAS366A SEPTEMBER 2006REVISED MAY 2013  
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REVISION HISTORY  
Rev  
Date  
Description  
1.0  
9/13/06  
Initial WEB release.  
Changes from Original (May 2013) to Revision A  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 13  
14  
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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)  
LM4674ATL/NOPB  
LM4674ATLX/NOPB  
ACTIVE  
ACTIVE  
DSBGA  
DSBGA  
YZR  
YZR  
16  
16  
250  
RoHS & Green  
SNAGCU  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 85  
-40 to 85  
GI2  
GI2  
3000 RoHS & Green  
SNAGCU  
(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 OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
5-Nov-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)  
LM4674ATL/NOPB  
LM4674ATLX/NOPB  
DSBGA  
DSBGA  
YZR  
YZR  
16  
16  
250  
178.0  
178.0  
8.4  
8.4  
2.08  
2.08  
2.08  
2.08  
0.76  
0.76  
4.0  
4.0  
8.0  
8.0  
Q1  
Q1  
3000  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
5-Nov-2021  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LM4674ATL/NOPB  
LM4674ATLX/NOPB  
DSBGA  
DSBGA  
YZR  
YZR  
16  
16  
250  
208.0  
208.0  
191.0  
191.0  
35.0  
35.0  
3000  
Pack Materials-Page 2  
MECHANICAL DATA  
YZR0016xxx  
D
0.600±0.075  
E
TLA16XXX (Rev C)  
D: Max = 1.99 mm, Min = 1.93 mm  
E: Max = 1.99 mm, Min = 1.93 mm  
4215051/A  
12/12  
A. All linear dimensions are in millimeters. Dimensioning and tolerancing per ASME Y14.5M-1994.  
B. This drawing is subject to change without notice.  
NOTES:  
www.ti.com  
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TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
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  
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