LM4674A
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SNAS366A – SEPTEMBER 2006 – REVISED MAY 2013
LM4674A
Filterless 2.5W Stereo Class D Audio Power
Amplifier
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FEATURES
DESCRIPTION
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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.
1
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
Available in Space-Saving 2mm x 2mm x
0.6mm DSBGA Package
APPLICATIONS
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Mobile Phones
PDAs
Laptops
KEY SPECIFICATIONS
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Efficiency at 3.6V, 100mW into 8Ω 80% (typ)
Efficiency at 3.6V, 500mW into 8Ω 85% (typ)
Efficiency at 5V, 1W into 8Ω 85% (typ)
Quiescent Power Supply Current at 3.6V
Supply 4mA
Power Output at VDD = 5V, RL = 4Ω, THD ≤ 10%
2.5W (typ)
Power Output at VDD = 5V, RL = 8Ω, THD ≤ 10%
1.5W (typ)
Shutdown Current 0.1μA (typ)
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 4Ω load with less than
10% THD+N. Flexible power supply requirements
allow operation from 2.4V to 5.5V.
The LM4674A features high efficiency compared to
conventional Class AB amplifiers. When driving an
8Ω speaker 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.
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.
1
2
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.
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 2006 – REVISED MAY 2013
www.ti.com
Typical Application
2.4V to 5.5V
PVDD
VDD
INR-
OUTRA
INR+
OUTRB
INL-
OUTLA
INL+
OUTLB
LM4674A
/SDR
SHUTDOWN
CONTROL
/SDL
GAIN0
GAIN
CONTROL
GAIN1
GND
PGND
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagram
4
OUTLB
/SDL
PGND
OUTRB
3
OUTLA
/SDR
GND
OUTRA
2
PVDD
G1
G0
VDD
1
INL+
INL-
INR-
INR+
A
B
C
D
Figure 2. DSBGA - Top View
See YZR0016 Package
2
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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
−65°C to +150°C
Storage Temperature
Input Voltage
Power Dissipation
–0.3V to VDD +0.3V
(4)
Internally Limited
ESD Susceptibility, all other pins (5)
2000V
ESD Susceptibility (6)
200V
Junction Temperature (TJMAX)
Thermal Resistance
(1)
(2)
(3)
(4)
(5)
(6)
150°C
θJA
45.7°C/W
All voltages are measured with respect to the ground pin, unless otherwise specified.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, θJA, and the ambient temperature,
TA. The maximum allowable power dissipation is PDMAX = (TJMAX – TA)/ θJA or the number given in Absolute Maximum Ratings,
whichever is lower. For the LM4674A see power derating currents for more information.
Human body model, 100pF discharged through a 1.5kΩ resistor.
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)
(2)
All voltages are measured with respect to the ground pin, unless otherwise specified.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
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LM4674A
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Electrical Characteristics VDD = 3.6V (1) (2)
The following specifications apply for AV = 6dB, RL = 15µH + 8Ω + 15µH, f = 1kHz unless otherwise specified. Limits apply for
TA = 25°C.
Symbol
VOS
Parameter
Differential Output Offset Voltage
LM4674A
Conditions
Typical (3)
VIN = 0, VDD = 2.4V to 5.0 V
5
VIN = 0, RL = ∞,
IDD
Quiescent Power Supply Current
Both channels active, VDD = 3.6V
VIN = 0, RL = ∞,
Both channels active, VDD = 5V
ISD
Shutdown Current
VSDIH
Shutdown Voltage Input High
VSDIL
Shutdown Voltage Input Low
TWU
Wake Up Time
AV
Gain
RIN
Input Resistance
Limit (4)
VSD1 = VSD2 = GND
VSHUTDOWN = 0.4V
mV
4
6
5
7.5
0.03
Units
(Limits)
mA
mA
1
μA
1.4
V (min)
0.4
V (max)
4.2
ms
GAIN0, GAIN1 = GND
6
6 ± 0.5
dB
GAIN0 = VDD, GAIN1 = GND
12
12 ± 0.5
dB
GAIN0 = GND, GAIN1 = VDD
18
18 ± 0.5
dB
GAIN0, GAIN1 = VDD
24
24 ± 0.5
AV = 6dB
28
kΩ
AV = 12dB
18.75
kΩ
AV = 18dB
11.25
kΩ
AV = 24dB
6.25
kΩ
2.5
W
VDD = 3.6V
1.2
W
VDD = 2.5V
0.530
W
dB
RL = 15μH + 4Ω + 15μH, THD = 10%
f = 1kHz, 22kHz BW
VDD = 5V
RL = 15μH + 8Ω + 15μH, THD = 10%
f = 1kHz, 22kHz BW
PO
Output Power
VDD = 5V
1.5
VDD = 3.6V
0.78
W
VDD = 2.5V
0.350
W
1.9
W
VDD = 3.6V
1
W
VDD = 2.5V
0.430
W
VDD = 5V
1.25
W
VDD = 3.6V
0.63
W
VDD = 2.5V
0.285
W
PO = 500mW, f = 1kHz, RL = 8Ω
0.07
%
PO = 300mW, f = 1kHz, RL = 8Ω
0.05
%
0.6
W
RL = 15μH + 4Ω + 15μH, THD = 1%
f = 1kHz, 22kHz BW
VDD = 5V
RL = 15μH + 8Ω + 15μH, THD = 1%
f = 1kHz, 22kHz BW
THD+N
(1)
(2)
(3)
(4)
4
Total Harmonic Distortion
All voltages are measured with respect to the ground pin, unless otherwise specified.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to TI's AOQL (Average Outgoing Quality Level).
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Electrical Characteristics VDD = 3.6V(1)(2) (continued)
The following specifications apply for AV = 6dB, RL = 15µH + 8Ω + 15µH, f = 1kHz unless otherwise specified. Limits apply for
TA = 25°C.
Symbol
Parameter
Conditions
LM4674A
Typical (3)
Limit (4)
Units
(Limits)
VRIPPLE = 200mVP-P Sine,
fRipple = 217Hz, Inputs AC GND,
PSRR
75
dB
75
dB
67
dB
85
%
dB
CI = 1μF, input referred
Power Supply Rejection Ratio
VRIPPLE = 1VP-P Sine,
fRipple = 1kHz, Inputs AC GND,
CI = 1μF, input referred
CMRR
Common Mode Rejection Ratio
η
Efficiency
VRIPPLE = 1VP-P
fRIPPLE = 217Hz
PO = 1W, f = 1kHz,
RL = 8Ω, VDD = 5V
Crosstalk
PO = 500mW, f = 1kHz
84
SNR
Signal to Noise Ratio
VDD = 5V, PO = 1W
96
dB
εOS
Output Noise
Input referred, A-Weighted Filter
20
μV
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 PF
1 PF
VDD
PVDD
1 PF
OUTRA
INRGAIN/
MODULATOR
1 PF
H-BRIDGE
INR+
OUTRB
/SDR
GAIN0
OSCILLATOR
GAIN1
/SDL
1 PF
OUTLA
INLGAIN/
MODULATOR
1 PF
H-BRIDGE
INL+
OUTLB
GND
PGND
PVDD VDD
OSCILLATOR
INL+
OUTLA
PWM MODULATOR
H-BRIDGE
INL-
OUTLB
G0
G1
GAIN
CONTROL
CLICK/POP
SUPPRESSION
BIAS
OUTRA
INR+
PWM MODULATOR
H-BRIDGE
OUTRB
INR-
PGND
GND /SDR
/SDL
Figure 3. Differential Input Configuration
6
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Typical Performance Characteristics
THD+N vs Output Power
f = 1kHz, AV = 24dB, RL = 8Ω
THD+N vs Output Power
f = 1kHz, AV = 6dB, RL = 8Ω
100
100
10
10
VDD = 5V
VDD = 3.6V
THD+N (%)
THD+N (%)
VDD = 3.6V
1
VDD = 2.5V
VDD = 5V
1
VDD = 2.5V
0.1
0.1
0.01
0.001
0.01
0.1
1
0.01
0.001
10
OUTPUT POWER (W)
1
10
OUTPUT POWER (W)
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
10
VDD = 5V
1
VDD = 2.5V
VDD = 5V
VDD = 3.6V
THD+N (%)
VDD = 3.6V
THD+N (%)
0.1
Figure 4.
100
1
VDD = 2.5V
0.1
0.1
0.01
0.001
0.01
0.1
1
0.01
0.001
10
OUTPUT POWER (W)
0.01
0.1
1
10
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
10
THD+N (%)
THD+N (%)
0.01
1
0.1
0.01
0.001
10
1
0.1
0.01
100
1000
10000
100000
0.001
10
100
1000
10000
FREQUENCY (W)
FREQUENCY (W)
Figure 8.
Figure 9.
100000
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Typical Performance Characteristics (continued)
THD+N vs Frequency
VDD = 2. 5V, POUT = 100mW, RL = 4Ω
100
100
10
10
THD+N (%)
THD+N (%)
THD+N vs Frequency
VDD = 5V, POUT = 375mW, RL = 8Ω
1
0.1
0.01
0.1
0.01
0.001
10
100
1000
10000
0.001
10
100000
10000
100000
FREQUENCY (W)
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
0.1
1
0.1
0.01
0.001
10
100
1000
10000
0.001
10
100000
100
1000
10000
FREQUENCY (W)
FREQUENCY (W)
Figure 12.
Figure 13.
Efficiency vs. Output Power
RL = 4Ω, f = 1kHz
Efficiency vs. Output Power
RL = 8Ω, f = 1kHz
100
100000
100
90
90
VDD = 5V
80
70
60
50
VDD = 3.6V
40
30
VDD = 5V
80
EFFICIENCY (%)
EFFICIENCY (%)
1000
Figure 10.
0.01
V DD = 2.5V
70
60
VDD = 3.6V
50
40
V DD = 2.5V
30
20
20
10
10
0
0
0
8
100
FREQUENCY (W)
THD+N (%)
THD+N (%)
1
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
RL = 4Ω, f = 1kHz
Power Dissipation vs. Output Power
RL = 8Ω, f = 1kHz
1000
400
VDD = 5V
POWER DISSIPATION (mW)
POWER DISSIPATION (mW)
VDD = 5V
VDD = 3.6V
750
V DD = 2.5V
500
250
300
VDD = 3.6V
V DD = 2.5V
200
100
POUT = P OUTL + P OUTR
0
0
1000
2000
3000
POUT = P OUTL + P OUTR
0
4000
0
500
OUTPUT POWER (mW)
1000
1500
2000
2500
OUTPUT POWER (mW)
Figure 16.
Figure 17.
Output Power vs. Supply Voltage
RL = 4Ω, f = 1kHz
Output Power vs. Supply Voltage
RL = 8Ω, f = 1kHz
3000
2000
OUTPUT POWER (mW)
OUTPUT POWER (mW)
2500
2000
THD+N = 10%
1500
THD+N = 1%
1000
1500
THD+N = 10%
1000
THD+N = 1%
500
500
0
2.5
3
3.5
4
4.5
5
0
2.5
5.5
SUPPLY VOLTAGE (V)
3.5
4
4.5
5
5.5
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
0
-10
-10
-20
CROSSTALK (dB)
-20
-30
PSRR (dB)
3
-40
-50
-60
-70
-40
-50
-60
-70
-80
-90
-80
-90
10
-30
100
1000
10000
100000
-100
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
8
-10
7
SUPPLY CURRENT (mA)
0
-20
CMRR(dB)
Supply Current vs. Supply Voltage
No Load
-30
-40
-50
-60
-70
-80
10
5
4
3
2
1
100
1000
10000
100000
FREQUENCY (Hz)
0
2.5
3
3.5
4
4.5
5
5.5
SUPPLY VOLTAGE (V)
Figure 22.
10
6
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 onresistance, 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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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
0
0
2
6
0
1
4
12
1
0
8
18
1
1
16
24
V/V
dB
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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Product Folder Links: LM4674A
LM4674A
www.ti.com
SNAS366A – SEPTEMBER 2006 – REVISED MAY 2013
PVDD VDD
OSCILLATOR
INL+
OUTLA
PWM MODULATOR
H-BRIDGE
INL-
OUTLB
G0
G1
GAIN
CONTROL
CLICK/POP
SUPPRESSION
BIAS
OUTRA
INR+
PWM MODULATOR
H-BRIDGE
OUTRB
INR-
PGND
GND /SDR
/SDL
Figure 24. Differential Input Configuration
PVDD VDD
OSCILLATOR
INL+
OUTLA
PWM MODULATOR
H-BRIDGE
INL-
OUTLB
G0
G1
GAIN
CONTROL
CLICK/POP
SUPPRESSION
BIAS
OUTRA
INR+
PWM MODULATOR
H-BRIDGE
OUTRB
INR-
PGND
GND /SDR
/SDL
Figure 25. Single-Ended Input Configuration
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Copyright © 2006–2013, Texas Instruments Incorporated
Product Folder Links: LM4674A
13
LM4674A
SNAS366A – SEPTEMBER 2006 – REVISED MAY 2013
www.ti.com
REVISION HISTORY
Rev
Date
Description
1.0
9/13/06
Initial WEB release.
Changes from Original (May 2013) to Revision A
•
14
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 13
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Copyright © 2006–2013, Texas Instruments Incorporated
Product Folder Links: LM4674A
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LM4674ATL/NOPB
ACTIVE
DSBGA
YZR
16
250
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
-40 to 85
GI2
LM4674ATLX/NOPB
ACTIVE
DSBGA
YZR
16
3000
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
-40 to 85
GI2
(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
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