LM4666 [TI]
Filterless High Efficiency Stereo 1.2W Switching;
| 型号： | LM4666 |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | Filterless High Efficiency Stereo 1.2W Switching |
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| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LM4666, LM4666SDBD
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SNAS189A –MAY 2004–REVISED MAY 2013
LM4666
Filterless High Efficiency Stereo 1.2W Switching
Audio Amplifier
Check for Samples: LM4666, LM4666SDBD
1
FEATURES
DESCRIPTION
The LM4666 is a fully integrated single-supply high
2
•
No Output Filter Required for Inductive
Transducers
efficiency switching audio amplifier. It features an
innovative modulator that eliminates the LC output
filter used with typical switching amplifiers.
Eliminating the output filter reduces parts count,
simplifies circuit design, and reduces board area. The
LM4666 processes analog inputs with a delta-sigma
modulation technique that lowers output noise and
THD when compared to conventional pulse width
modulators.
•
•
•
•
•
•
•
Selectable Gain of 6dB or 12dB
Very Fast Turn On Time: 6ms (typ)
Minimum External Components
"Click and Pop" Suppression Circuitry
Micro-Power Shutdown Mode
Short Circuit Protection
Available in Space-Saving NHK0014A Package
The LM4666 is designed to meet the demands of
mobile phones and other portable communication
devices. Operating on a single 3V supply, it is
APPLICATIONS
capable of driving 8Ω transducer loads at
a
•
•
•
Mobile Phones
PDAs
continuous average output of 450mW with less than
1%THD+N. Its flexible power supply requirements
allow operation from 2.8V to 5.5V.
Portable Electronic Devices
The LM4666 has high efficiency with an 8Ω
transducer load compared to a typical Class AB
amplifier. With a 3V supply, the IC's efficiency for a
100mW power level is 79%, reaching 84% at 450mW
output power.
KEY SPECIFICATIONS
•
•
•
•
•
•
Efficiency at 3V, 100mW into 8Ω Transducer:
79% (typ)
Efficiency at 3V, 450mW into 8Ω Transducer:
84% (typ)
The LM4666 features a low-power consumption
shutdown mode. Shutdown may be enabled by
driving the Shutdown pin to a logic low (GND).
Efficiency at 5V, 1W into 8Ω Transducer: 85%
(typ)
The LM4666 has fixed selectable gain of either 6dB
or 12dB. The LM4666 has short circuit protection
against a short from the outputs to VDD or GND.
Total Quiescent Power Supply Current: 7.0mA
(typ)
Total Shutdown Power Supply Current: 0.02µA
(typ)
Single supply range: 2.8V to 5.5V
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.
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Typical Application
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagram
Top View
Figure 2. WSON Package
See Package Number NHK0014A
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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
Storage Temperature
−65°C to +150°C
Voltage at Any Input Pin
Power Dissipation(4)
ESD Susceptibility, pins 4, 7, 11, 14(5)
ESD Susceptibility, all other pins(5)
ESD Susceptibility(6)
VDD + 0.3V ≥ V ≥ GND - 0.3V
Internally Limited
1kV
2.0kV
200V
Junction Temperature (TJ)
150°C
θJA (NHK0014A)
θJC (NHK0014A)
63°C/W
12°C/W
Thermal Resistance
Soldering Information: See AN-1112 (SNVA009) "microSMD Wafers Level Chip Scale Package."
(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 specified 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 LM4666, TJMAX = 150°C. The typical θJA is 63°C/W and the typical θJC is 12°C/W for the NHK0014A package.
(5) Human body model, 100pF discharged through a 1.5kΩ resistor.
(6) Machine Model, 220pF – 240pF discharged through all pins.
Operating Ratings(1)(2)
Temperature Range
TMIN ≤ TA ≤ TMAX
−40°C ≤ TA ≤ 85°C
2.8V ≤ 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 specified for parameters where no limit is given, however, the typical value is a good indication
of device performance.
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Electrical Characteristics VDD = 5V(1)(2)
The following specifications apply for VDD = 5V and RL = 15µH + 8Ω + 15µH unless otherwise specified. Limits apply for TA =
25°C.
LM4666
Limit(4)(5)
Units
(Limits)
Parameter
Test Conditions
VIN = 0V, No Load
Typ(3)
IDD
Quiescent Power Supply Current
15
16
mA
mA
VIN = 0V, RL = 15µH + 8Ω + 15µH
ISD
Shutdown Current
VSD = GND(6)
0.02
1.2
1.1
1.2
1.1
6
µA
V
VSDIH
VSDIL
VGSIH
VGSIL
AV
Shutdown Voltage Input High
Shutdown Voltage Input Low
Gain Select Input High
Gain Select Input Low
Closed Loop Gain
V
V
V
VGain Select = VDD
VGain Select = GND
dB
dB
mV
ms
AV
Closed Loop Gain
12
10
6
VOS
TWU
Output Offset Voltage
Wake-up Time
THD = 1% (max), f = 1kHz,
22kHz BW
Po
Output Power
1.2
W
PO = 100mWRMS/Channel,
fIN = 1kHz, 22kHz BW,
Both channels in phase
THD+N
Total Harmonic Distortion+Noise
0.65
%
XTALK
RIN
Channel Separation
PO = 100mWRMS, f = 1kHz
VGain Select = VDD
57
90
60
dB
kΩ
kΩ
Differential Input Resistance
VGain Select = GND
VRipple = 100mVRMS sine wave,
fRIPPLE = 217Hz
60
dB
Inputs terminated to AC GND
PSRR
CMRR
Power Supply Rejection Ratio
Common Mode Rejection Ratio
VRipple = 100mVRMS sine wave,
fRIPPLE = 217Hz
POUT = 10mW,1kHz
65
48
dB
dB
VRipple = 100mVRMS
,
fRipple = 217Hz, Input referred
PO = 1WRMS; A-Weighted Filter
A-Weighted filter, Vin = 0V
SNR
Signal to Noise Ratio
Output Noise
83
dB
µV
εOUT
200
(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 specified for parameters where no limit is given, however, the typical value is a good indication
of device performance.
(3) Typical specifications are specified at 25°C and represent the parametric norm.
(4) Tested limits are specified to AOQL (Average Outgoing Quality Level).
(5) Datasheet min/max specification limits are specified by design, test, or statistical analysis.
(6) Shutdown current is measured in a normal room environment. Exposure to direct sunlight will increase ISD by a maximum of 2µA. The
Shutdown pin should be driven as close as possible to GND for minimal shutdown current and to VDD for the best THD performance in
PLAY mode. See the Application Information section under SHUTDOWN FUNCTION for more information.
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Electrical Characteristics VDD = 3V(1)(2)
The following specifications apply for VDD = 3V and RL = 15µH + 8Ω + 15µH unless otherwise specified. Limits apply for TA =
25°C.
LM4666
Limit(4)(5)
Units
(Limits)
Parameter
Test Conditions
VIN = 0V, No Load
Typ(3)
IDD
Quiescent Power Supply Current
6.5
7.0
10
mA (max)
VIN = 0V, RL = 15µH + 8Ω + 15µH
ISD
Shutdown Current
VSD = GND(6)
0.02
1.0
0.8
1.0
0.8
2.0
1.4
0.4
1.4
0.4
µA (max)
V (min)
V (max)
V (min)
V (max)
VSDIH
VSDIL
VGSIH
VGSIL
Shutdown Voltage Input High
Shutdown Voltage Input Low
Gain Select Input High
Gain Select Input Low
5.25
6.75
dB (min)
dB (max)
AV
AV
Closed Loop Gain
Closed Loop Gain
VGain Select = VDD
VGain Select = GND
6
11.25
12.75
dB (min)
dB (max)
12
VOS
TWU
Output Offset Voltage
Wake-up Time
10
6
35
mV (max)
ms
THD = 1% (max); f = 1kHz,
22kHz BW
Po
Output Power
450
400
mW (min)
PO = 100mWRMS/Channel,
fIN = 1kHz, 22kHz BW,
Both channels in phase
THD+N
Total Harmonic Distortion+Noise
0.65
%
XTALK
RIN
Channel Separation
PO = 100mWRMS, f = 1kHz
VGain Select = VDD
57
90
60
dB
kΩ
kΩ
Differential Input Resistance
VGain Select = GND
Vripple = 100mVRMS sine wave,
fRIPPLE = 217Hz,
60
dB
Inputs terminated to AC GND
PSRR
CMRR
Power Supply Rejection Ratio
Common Mode Rejection Ratio
VRipple = 100mVRMS sine wave,
fRIPPLE = 217Hz,
POUT = 10mW,1kHz
65
48
dB
dB
VRipple = 100mVRMS
,
fRipple = 217Hz, Input referred
PO = 400mWRMS, A-Weighted Filter
A-Weighted filter, Vin = 0V
SNR
Signal to Noise Ratio
Output Noise
83
dB
µV
εOUT
125
(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 specified for parameters where no limit is given, however, the typical value is a good indication
of device performance.
(3) Typical specifications are specified at 25°C and represent the parametric norm.
(4) Tested limits are specified to AOQL (Average Outgoing Quality Level).
(5) Datasheet min/max specification limits are specified by design, test, or statistical analysis.
(6) Shutdown current is measured in a normal room environment. Exposure to direct sunlight will increase ISD by a maximum of 2µA. The
Shutdown pin should be driven as close as possible to GND for minimal shutdown current and to VDD for the best THD performance in
PLAY mode. See the Application Information section under SHUTDOWN FUNCTION for more information.
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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Typical Performance Characteristics(1)
THD+N vs Frequency
THD+N vs Frequency
VDD = 3V, RL = 15µH + 8Ω + 15µH
POUT = 100mW/Channel, 30kHz BW
VDD = 5V, RL = 15µH + 8Ω + 15µH
POUT = 100mW/Channel, 30kHz BW
Figure 3.
Figure 4.
THD+N vs Frequency
VDD = 3V, RL = 15µH + 4Ω + 15µH
POUT = 100mW/Channel, 30kHz BW
THD+N vs Output Power/Channel
VDD = 5V, RL = 15µH + 8Ω + 15µH
f = 1kHz, 22kHz BW
Figure 5.
Figure 6.
THD+N vs Output Power/Channel
VDD = 3V, RL = 15µH + 4Ω + 15µH
f = 1kHz, 22kHz BW
THD+N vs Output Power/Channel
VDD = 3V, RL = 15µH + 8Ω + 15µH
f = 1kHz, 22kHz BW
Figure 7.
Figure 8.
(1) The performance graphs were taken using the Audio Precision AUX–0025 Switching Amplifier Measurement Filter in series with the LC
filter on the demo board.
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Typical Performance Characteristics(1) (continued)
CMRR vs Frequency
VDD = 5V, RL = 15µH + 8Ω + 15µH
VCM = 100mVRMS Sine Wave, 30kHz BW
CMRR vs Frequency
VDD = 3V, RL = 15µH + 8Ω + 15µH
VCM = 100mVRMS Sine Wave, 30kHz BW
Figure 9.
Figure 10.
PSRR vs Frequency
VDD = 5V, RL = 15µH + 8Ω + 15µH
VRipple = 100mVRMS Sine Wave, 22kHz BW
PSRR vs Frequency
VDD = 3V, RL = 15µH + 8Ω + 15µH
VRipple = 100mVRMS Sine Wave, 22kHz BW
Figure 11.
Figure 12.
Efficiency and Power Dissipation
vs Output Power
VDD = 5V, RL = 15µH + 8Ω + 15µH, f = 1kHz, THD ≤ 1%
Efficiency and Power Dissipation
vs Output Power
VDD = 3V, RL = 15µH + 8Ω + 15µH, f = 1kHz, THD ≤ 1%
Figure 13.
Figure 14.
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Typical Performance Characteristics(1) (continued)
Efficiency and Power Dissipation
vs Output Power
Gain Select Threshold
VDD = 3V
VDD = 3V, RL = 15µH + 4Ω + 15µH, f = 1kHz, THD ≤ 1%
Figure 15.
Figure 16.
Gain Select Threshold
vs Supply Voltage
RL = 15µH + 8Ω + 15µH
Gain Select Threshold
VDD = 5V
Figure 17.
Figure 18.
Output Power/Channel vs Supply Voltage
RL = 15µH + 8Ω + 15µH, f = 1kHz
22kHz BW
Output Power/Channel vs Supply Voltage
RL = 15µH + 4Ω + 15µH, f = 1kHz
22kHz BW
Figure 19.
Figure 20.
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Typical Performance Characteristics(1) (continued)
Shutdown Threshold
VDD = 5V
Shutdown Threshold
VDD = 3V
Figure 21.
Figure 22.
Shutdown Threshold vs Supply Voltage
RL = 15µH + 8Ω + 15µH
Figure 23.
Supply Current vs Shutdown Voltage
Supply Current vs Supply Voltage
RL = 15µH + 8Ω + 15µH
RL = 15µH + 8Ω + 15µH
Figure 24.
Figure 25.
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APPLICATION INFORMATION
GENERAL AMPLIFIER FUNCTION
The output signals generated by the LM4666 consist of two, BTL connected, output signals that pulse
momentarily from near ground potential to VDD on each channel. The two outputs on a given channel can pulse
independently with the exception that they both may never pulse simultaneously as this would result in zero volts
across the BTL connected load. The minimum width of each pulse is approximately 160ns. However, pulses on
the same output can occur sequentially, in which case they are concatenated and appear as a single wider pulse
to achieve an effective 100% duty cycle. This results in maximum audio output power for a given supply voltage
and load impedance. The LM4666 can achieve much higher efficiencies than class AB amplifiers while
maintaining acceptable THD performance.
The short (160ns) drive pulses emitted at the LM4666 outputs means that good efficiency can be obtained with
minimal load inductance. The typical transducer load on an audio amplifier is quite reactive (inductive). For this
reason, the load can act as it's own filter, so to speak. This "filter-less" switching amplifier/transducer load
combination is much more attractive economically due to savings in board space and external component cost
by eliminating the need for a filter.
POWER DISSIPATION AND EFFICIENCY
In general terms, efficiency is considered to be the ratio of useful work output divided by the total energy required
to produce it with the difference being the power dissipated, typically, in the IC. The key here is “useful” work. For
audio systems, the energy delivered in the audible bands is considered useful including the distortion products of
the input signal. Sub-sonic (DC) and super-sonic components (>22kHz) are not useful. The difference between
the power flowing from the power supply and the audio band power being transduced is dissipated in the
LM4666 and in the transducer load. The amount of power dissipation in the LM4666 is very low. This is because
the ON resistance of the switches used to form the output waveforms is typically less than 0.25Ω. This leaves
only the transducer load as a potential "sink" for the small excess of input power over audio band output power.
The LM4666 dissipates only a fraction of the excess power requiring no additional PCB area or copper plane to
act as a heat sink.
DIFFERENTIAL AMPLIFIER EXPLANATION
As logic supply voltages continue to shrink, designers are increasingly turning to differential analog signal
handling to preserve signal to noise ratios with restricted voltage swing. The LM4666 is a fully differential
amplifier that features differential input and output stages. 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 in signal to noise ratio relative to differential inputs. The LM4666 also offers the possibility of
DC input coupling which eliminates the two external AC coupling, DC blocking capacitors. The LM4666 can be
used, however, as a single ended input amplifier while still retaining it's fully differential benefits. In fact,
completely unrelated signals may be placed on the input pins. The LM4666 simply amplifies the difference
between the signals. A major benefit of a differential amplifier is the improved common mode rejection ratio
(CMRR) over single input amplifiers. The common-mode rejection characteristic of the differential amplifier
reduces sensitivity to ground offset related noise injection, especially important in high noise applications.
PCB LAYOUT CONSIDERATIONS
As output power increases, interconnect resistance (PCB traces and wires) between the amplifier, load and
power supply create a voltage drop. The voltage loss on the traces between the LM4666 and the load results is
lower output power and decreased efficiency. Higher trace resistance between the supply and the LM4666 has
the same effect as a poorly regulated supply, increase ripple on the supply line also reducing the 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.
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The rising and falling edges are necessarily short in relation to the minimum pulse width (160ns), having
approximately 2ns rise and fall times, typical, depending on parasitic output capacitance. The inductive nature of
the transducer load can also result in overshoot on one or 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. It is essential to keep the power and output traces short
and well shielded if possible. Use of ground planes, beads, and micro-strip layout techniques are all useful in
preventing unwanted interference.
As the distance from the LM4666 and the speakers increase the amount of EMI radiation will increase since the
output wires or traces acting as antenna become more efficient with length. What is acceptable EMI is highly
application specific. Ferrite chip inductors placed close to the LM4666 may be needed to reduce EMI radiation.
The value of the ferrite chip is very application specific.
POWER SUPPLY BYPASSING
As with any power amplifier, proper supply bypassing is critical for low noise performance and high power supply
rejection ratio (PSRR). The capacitor (CS) location should be as close as possible to the LM4666. Typical
applications employ a voltage regulator with a 10µF and a 0.1µF bypass capacitors that increase supply stability.
These capacitors do not eliminate the need for bypassing on the supply pin of the LM4666. A 1µF tantalum
capacitor is recommended.
SHUTDOWN FUNCTION
In order to reduce power consumption while not in use, the LM4666 contains shutdown circuitry that reduces
current draw to less than 0.01µA. The trigger point for shutdown is shown as a typical value in the Electrical
Characteristics Tables and in the Shutdown Hysteresis Voltage graphs found in the Typical Performance
Characteristics section. It is best to switch between ground and supply for minimum current usage while in the
shutdown state. While the LM4666 may be disabled with shutdown voltages in between ground and supply, the
idle current will be greater than the typical value. Increased THD may also be observed with voltages less than
VDD on the Shutdown pin when in PLAY mode.
The LM4666 has an internal resistor connected between GND and Shutdown pins. The purpose of this resistor is
to eliminate any unwanted state changes when the Shutdown pin is floating. The LM4666 will enter the shutdown
state when the Shutdown pin is left floating or if not floating, when the shutdown voltage has crossed the
threshold. To minimize the supply current while in the shutdown state, the Shutdown pin should be driven to
GND or left floating. If the Shutdown pin is not driven to GND, the amount of additional resistor current due to the
internal shutdown resistor can be found by Equation 1 below.
(VSD - GND) / 60kΩ
(1)
With only a 0.5V difference, an additional 8.3µA of current will be drawn while in the shutdown state.
GAIN SELECTION FUNCTION
The LM4666 has fixed selectable gain to minimize external components, increase flexibility and simplify design.
For a differential gain of 6dB, the Gain Select pin should be permanently connected to VDD or driven to a logic
high level. For a differential gain of 12dB, the Gain Select pin should be permanently connected to GND or driven
to a logic low level. The gain of the LM4666 can be switched while the amplifier is in PLAY mode driving a load
with a signal without damage to the IC. The voltage on the Gain Select pin should be switched quickly between
GND (logic low) and VDD (logic high) to eliminate any possible audible artifacts from appearing at the output. For
typical threshold voltages for the Gain Select function, refer to the Gain Threshold Voltages graph in the Typical
Performance Characteristics section.
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CIRCUIT CONFIGURATIONS
Figure 26. Single-Ended Input with Low Gain Selection Configuration
Figure 27. Differential Input with Low Gain Selection Configuration
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REFERENCE DESIGN BOARD SCHEMATIC
Figure 28.
In addition to the minimal parts required for the application circuit, a measurement filter is provided on the
evaluation circuit board so that conventional audio measurements can be conveniently made without additional
equipment. This is a balanced input, grounded differential output low pass filter with a 3dB frequency of
approximately 35kHz and an on board termination resistor of 300Ω (see Figure 28). Note that the capacitive load
elements are returned to ground. This is not optimal for common mode rejection purposes, but due to the
independent pulse format at each output there is a significant amount of high frequency common mode
component on the outputs. The grounded capacitive filter elements attenuate this component at the board to
reduce the high frequency CMRR requirement placed on the analysis instruments.
Even with the grounded filter the audio signal is still differential necessitating a differential input on any analysis
instrument connected to it. Most lab instruments that feature BNC connectors on their inputs are NOT differential
responding because the ring of the BNC is usually grounded.
The commonly used Audio Precision analyzer is differential but its ability to accurately reject fast pulses of 160ns
width is questionable necessitating the on board measurement filter. When the signal needs to be single-ended,
use an audio signal transformer to convert the differential output to a single ended output. Depending on the
audio transformer's characteristics, there may be some attenuation of the audio signal which needs to be taken
into account for correct measurement of performance.
Measurements made at the output of the measurement filter suffer attenuation relative to the primary, unfiltered
outputs even at audio frequencies. This is due to the resistance of the inductors interacting with the termination
resistor (300Ω) and is typically about -0.35dB (4%). In other words, the voltage levels and corresponding power
levels indicated through the measurement filter are slightly lower than those that actually occur at the load placed
on the unfiltered outputs. This small loss in the filter for measurement gives a lower output power reading than
what is really occurring on the unfiltered outputs and its load.
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SNAS189A –MAY 2004–REVISED MAY 2013
www.ti.com
The AUX-0025 Switching Amplifier Measurement Filter from Audio Precision may be used instead of the on
board measurement filter. The AUX-0025 filter should be connected to the high current direct outputs on the
evaluation board and in series with the measurement equipment. Attaching oscilloscope probes on the outputs of
the AUX-0025 filter will display the audio waveforms. The AUX-0025 filter may also be connected to the on board
filter without any adverse effects.
LM4666 NHK0014A BOARD ARTWORK
Figure 29. Composite View
Figure 30. Silk Screen
14
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Product Folder Links: LM4666 LM4666SDBD
LM4666, LM4666SDBD
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SNAS189A –MAY 2004–REVISED MAY 2013
Figure 31. Top Layer
Figure 32. Internal Layer 1, GND
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SNAS189A –MAY 2004–REVISED MAY 2013
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Figure 33. Internal Layer 2, VDD
Figure 34. Bottom Layer
16
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Product Folder Links: LM4666 LM4666SDBD
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SNAS189A –MAY 2004–REVISED MAY 2013
REVISION HISTORY
Changes from Original (May 2013) to Revision A
Page
•
Changed layout of National Data Sheet to TI format .......................................................................................................... 16
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Product Folder Links: LM4666 LM4666SDBD
PACKAGE OPTION ADDENDUM
www.ti.com
9-Aug-2013
PACKAGING INFORMATION
Orderable Device
Status Package Type Package Pins Package
Eco Plan Lead/Ball Finish
MSL Peak Temp
Op Temp (°C)
Device Marking
Samples
Drawing
Qty
(1)
(2)
(3)
(4/5)
LM4666SD/NOPB
ACTIVE
WSON
NHK
14
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
L4666
(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) 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.
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
12-Aug-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)
LM4666SD/NOPB
WSON
NHK
14
1000
178.0
12.4
3.3
4.3
1.0
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Aug-2013
*All dimensions are nominal
Device
Package Type Package Drawing Pins
WSON NHK 14
SPQ
Length (mm) Width (mm) Height (mm)
210.0 185.0 35.0
LM4666SD/NOPB
1000
Pack Materials-Page 2
MECHANICAL DATA
NHK0014A
SDA14A (Rev A)
www.ti.com
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