LM4953, LM4953SDBD
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LM4953 Boomer™ Audio Power Amplifier Series Ground-Referenced, Ultra Low Noise,
Ceramic Speaker Driver
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FEATURES
DESCRIPTION
•
The LM4953 is an audio power amplifier designed for
driving Ceramic Speaker in portable applications.
When powered by a 3.6V supply, it is capable of
forcing 12.6Vpp across a 2μF + 30Ω bridge-tied-load
(BTL) with less than 1% THD+N.
1
23
•
•
•
•
•
•
Pop & Click Circuitry Eliminates Noise During
Turn-On and Turn-Off Transitions
Low, 1μA (Max) Shutdown Current
Low, 7mA (Typ) Quiescent Current
12.6Vpp Mono BTL Output, Load = 2μF+ 30Ω
Thermal Shutdown
Unity-Gain Stable
External Gain Configuration Capability
APPLICATIONS
•
•
Cellphone
PDA
KEY SPECIFICATIONS
•
•
•
Quiescent Power Supply Current (Vdd = 3V),
7mA(Typ)
BTL Voltage Swing
(2μF+30Ω load, 1% THD+N, Vdd = 3.6V), 12.6Vpp
(Typ)
Shutdown Current, 1µA (Max)
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4953 does not require bootstrap capacitors, or
snubber circuits. Therefore it is ideally suited for
display applications requiring high power and minimal
size.
The LM4953 features a low-power consumption
shutdown mode. Additionally, the LM4953 features an
internal thermal shutdown protection mechanism.
The LM4953 contains advanced pop & click circuitry
that eliminates noises which would otherwise occur
during turn-on and turn-off transitions.
The LM4953 is unity-gain stable and can be
configured by external gain-setting resistors.
1
2
3
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.
Boomer is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005–2006, Texas Instruments Incorporated
LM4953, LM4953SDBD
SNAS299E – SEPTEMBER 2005 – REVISED FEBRUARY 2006
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Typical Application
20 k:
CPVDD
Rf
+
C3
10
0.39 PF
+
Ci
20 k:
SHUTDOWN
*C4
13
Ri
Vin1
4.7 PF
1
4.7 PF
2
Undervoltage
Lockout,
Click/Pop
Suppression
and Shutdown
Control
11
15:
+
Ceramic
Speaker
2 PF
3
Charge
Pump
C1
2.2 PF
+
5
9
-
15:
100 k:
6
4
8
14
C2
2.2 PF
20 k:
Figure 1. Typical Application Circuit
Connection Diagram
SD
1
14
SGND
CPVDD
2
13
VIN
CCP+
3
12
NC
PGND
4
11
OUT A
CCP-
5
10
AVDD
VCP_OUT
6
9
OUT B
NC
7
8
AVSS
Figure 2. WSON Package
Top View
See Package Number NHK0014A
2
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PIN DESCRIPTIONS
Pin
Name
Function
1
SD
Active Low Shutdown
2
CPVDD
Charge Pump Power Supply
3
CCP+
Positive Terminal - Charge Pump Flying
Capacitor
4
PGND
Power Ground
5
CCP-
Negative Terminal - Charge Pump Flying
Capacitor
6
VCP_OUT
Charge Pump Output
7
NC
No Connect
8
AVSS
Negative Power Supply - Amplifier
9
OUT B
Output B
10
AVDD
Positive Power Supply - Amplifier
11
OUT A
Output A
12
NC
No Connect
13
VIN
Signal Input
14
SGND
Signal Ground
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
Absolute Maximum Ratings (1) (2) (3)
Supply Voltage (VDD)
4.5V
Storage Temperature
−65°C to +150°C
Input Voltage
Power Dissipation
-0.3V to VDD + 0.3V
(4)
Internally Limited
ESD Susceptibility (5) (6)
2000V
ESD Susceptibility (7) (6)
200V
Junction Temperature
150°C
Thermal Resistance
See AN-1187(SNOA401) 'Leadless Leadframe Packaging (LLP).'
(1)
(2)
(3)
(4)
(5)
(6)
(7)
All voltages are measured with respect to the GND 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 that ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given; however, the typical value is a good indication
of device performance.
If Military/Aerospace specified devices are required, please contact the Texas Instruments 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 LM4xxx typical application (shown in Figure 1) with VDD = yyV, RL = 2μF+30Ω mono BTL operation the total
power dissipation is xxxW. θJA = 40°C/W.
Human body model, 100pF discharged through a 1.5kΩ resistor.
If the product is in shutdown mode and VDD exceeds 3.6V (to a max of 4V VDD), then most of the excess current will flow through the
ESD protection circuits. If the source impedance limits the current to a max of 10mA, then the part will be protected. If the part is
enabled when VDD is above 4V, circuit performance will be curtailed or the part may be permanently damaged.
Machine Model, 220pF-240pF discharged through all pins.
Operating Ratings
TMIN ≤ TA ≤ TMAX
Temperature Range
−40°C ≤ TA ≤ 85°C
1.6V ≤ VDD ≤ 4.2V
Supply Voltage (VDD)
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Electrical Characteristics VDD = 3.6V
The following specifications apply for VDD = 3.6V, AV-BTL = 6dB, ZL = 2μF+30Ω unless otherwise specified. Limits apply to TA =
25°C. See Figure 1.
Symbol
Parameter
Conditions
LM4953
Typ (1)
Units (Limits)
Limit (2) (3)
IDD
Quiescent Power Supply
Current
VIN = 0, RLOAD = 2μF+30Ω
8
mA (max)
Istandby
Quiescent Power Supply
Current Auto Standby Mode
VIN = 0, ZLOAD = 2μF+30Ω
2.7
mA
ISD
Shutdown Current
VSD = GND
0.1
VSDIH
Shutdown Voltage Input High
SD1
SD2
0.7*CPVdd
VSDIL
Shutdown Voltage Input Low
SD1
SD2
0.3*CPVdd
TWU
Wake-up Time
VOS
Output Offset Voltage
VOUT
Output Voltage Swing
THD = 1% (max); f = 1kHz
RL = 2μF+30Ω, Mono BTL
12.6
Vpp
THD+N
Total Harmonic Distortion +
Noise
VOUT = 6Vp-p, fIN = 1kHz
0.02
%
∈OS
Output Noise
A-Weighted Filter, VIN = 0V
15
μV
VRIPPLE = 200mVp-p, f = 217Hz,
Input Referred
67
dB
VRIPPLE = 200mVp-p, f = 1kHz,
Input Referred
65
dB
ZL = 2μF+30Ω, VOUT = 6Vp-p
105
dB
PSRR
SNR
(1)
(2)
(3)
4
Power Supply Rejection Ratio
Signal-to-Noise Ratio
1
V (min)
V (max)
μsec
125
1
µA (max)
10
mV (max)
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to Texas Instruments' AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test, or statistical analysis.
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Electrical Characteristics VDD = 3.0V
The following specifications apply for VDD = 3.0V, AV-BTL = 6dB, ZL = 2μF+30Ω unless otherwise specified. Limits apply to TA =
25°C. See Figure 1.
Symbol
Parameter
Conditions
LM4953
Units (Limits)
Typ (1)
Limit (2) (3)
10
IDD
Quiescent Power Supply
Current
VIN = 0, ZLOAD = 2μF+30Ω
7
Istandby
Quiescent Power Supply
Current Auto Standby Mode
VIN = 0, ZLOAD = 2μF+30Ω
2.3
ISD
Shutdown Current
VSD-LC = VSD-RC = GND
0.1
VSDIH
Shutdown Voltage Input High
SD1
SD2
0.7*CPVdd
VSDIL
Shutdown Voltage Input Low
SD1
SD2
0.3*CPVdd
TWU
Wake-up Time
VOS
Output Offset Voltage
VOUT
Output Voltage Swing
THD = 1% (max); f = 1kHz
ZL = 2μF+30Ω, Mono BTL
10.2
Vpp
THD+N
Total Harmonic Distortion +
Noise
VOUT = 8.5Vp-p, fIN = 1kHz
0.02
%
∈OS
Output Noise
A-Weighted Filter, VIN = 0V
15
μV
VRIPPLE = 200mVp-p, f = 217Hz,
Input Referred
73
dB
VRIPPLE = 200mVp-p, f = 1kHz,
Input Referred
68
dB
ZL = 2μF+30Ω, VOUT = 8.5Vp-p
105
dB
PSRR
SNR
(1)
(2)
(3)
mA
1
Power Supply Rejection Ratio
Signal-to-Noise Ratio
µA (max)
V (min)
V (max)
μsec
125
1
mA (max)
10
mV (max)
Typicals are measured at 25°C and represent the parametric norm.
Limits are specified to Texas Instruments' AOQL (Average Outgoing Quality Level).
Datasheet min/max specification limits are specified by design, test, or statistical analysis.
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Typical Performance Characteristics
THD+N vs Frequency
VDD = 3V, VO = 6Vpp, ZL = 2μF+30Ω
10
10
1
1
THD+N (%)
THD+N (%)
THD+N vs Frequency
VDD = 2V, VO = 2Vpp, ZL = 2μF+30Ω
0.1
0.01
0.01
0.001
20
100
1000
20000
0.001
20
20000
1000
100
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 3.
Figure 4.
THD+N vs Frequency
VDD = 3.6V, VO = 8.5Vpp, ZL = 2μF+30Ω
THD+N vs Frequency
VDD = 4.2V, VO = 10Vpp, ZL = 2μF+30Ω
10
10
1
1
THD+N (%)
THD+N (%)
0.1
0.1
0.01
0.01
0.001
20
0.1
1000
100
20000
0.001
20
100
20000
1000
FREQUENCY (Hz)
FREQUENCY(Hz)
Figure 5.
Figure 6.
THD+N vs Output Voltage
VDD = 2V, f = 1kHz, ZL = 2μF+30Ω
THD+N vs Output Voltage
VDD = 3V, f = 1kHz, ZL = 2μF+30Ω
10
1
THD+N (%)
THD+N (%)
1
0.1
0.01
0.01
0.001
0.1
0.6 0.8 1
1.2 1.4 1.6 1.8 2.0 2.2 2.4
OUTPUT VOLTAGE SWING (Vrms)
0.001
0.5
1.0
Figure 7.
6
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1.5
2.0
2.5
3.0
3.5
4.0
OUTPUT VOLTAGE SWING (Vrms)
Figure 8.
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Typical Performance Characteristics (continued)
THD+N vs Output Voltage
VDD = 4.2V, f = 1kHz, ZL = 2μF+30Ω
10
10
1
1
THD+N (%)
THD+N (%)
THD+N vs Output Voltage
VDD = 3.6V, f = 1kHz, ZL = 2μF+30Ω
0.1
0.01
0.1
0.01
0.001
0.5 1 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
0.001
2
5
PSRR vs Frequency
VDD = 2V, ZL = 2μF+30Ω
PSRR vs Frequency
VDD = 3V, ZL = 2μF+30Ω
-10
-10
-20
-20
-30
-30
-40
-50
-60
-70
-70
1k
10k
-80
10
100k
100
1k
10k
Figure 12.
PSRR vs Frequency
VDD = 3.6V, ZL = 2μF+30Ω
PSRR vs Frequency
VDD = 4.2V, ZL = 2μF+30Ω
0
-10
-10
-20
-20
-30
-30
PSRR (dB)
0
-40
-50
-40
-50
-60
-60
-70
-70
1k
100k
FREQUENCY (Hz)
Figure 11.
100
7
-50
-60
100
6
-40
FREQUENCY (Hz)
PSRR (dB)
4
Figure 10.
0
-80
10
3
Figure 9.
0
-80
10
1
OUTPUT VOLTAGE SWING (Vrms)
PSRR (dB)
PSRR (dB)
OUTPUT VOLTAGE SWING (Vrms)
10k
100k
-80
10
FREQUENCY (Hz)
100
1k
10k
100k
FREQUENCY (Hz)
Figure 13.
Figure 14.
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Typical Performance Characteristics (continued)
12
Supply Current vs Supply Voltage
ZL = 2μF+30Ω
SUPPLY CURRENT (mA)
10
Full Power Mode
8
6
Auto-Standby Mode
4
2
0
1.5
2
2.5
3
3.5
4
SUPPLY VOLTAGE (V)
Figure 15.
8
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APPLICATION INFORMATION
ELIMINATING THE OUTPUT COUPLING CAPACITOR
The LM4953 features a low noise inverting charge pump that generates an internal negative supply voltage. This
allows the outputs of the LM4953 to be biased about GND instead of a nominal DC voltage, like traditional
headphone amplifiers. Because there is no DC component, the large DC blocking capacitors (typically 220µF)
are not necessary. The coupling capacitors are replaced by two, small ceramic charge pump capacitors, saving
board space and cost.
Eliminating the output coupling capacitors also improves low frequency response. In traditional headphone
amplifiers, the headphone impedance and the output capacitor form a high pass filter that not only blocks the DC
component of the output, but also attenuates low frequencies, impacting the bass response. Because the
LM4953 does not require the output coupling capacitors, the low frequency response of the device is not
degraded by external components.
In addition to eliminating the output coupling capacitors, the ground referenced output nearly doubles the
available dynamic range of the LM4953 when compared to a traditional headphone amplifier operating from the
same supply voltage.
BRIDGE CONFIGURATION EXPLANATION
The Audio Amplifier portion of the LM4953has two internal amplifiers allowing different amplifier configurations.
The first amplifier’s gain is externally configurable, whereas the second amplifier is internally fixed in a unity-gain,
inverting configuration. The closed-loop gain of the first amplifier is set by selecting the ratio of Rf to Ri while the
second amplifier’s gain is fixed by the two internal 20kΩ resistors. Figure 1 shows that the output of amplifier one
serves as the input to amplifier two. This results in both amplifiers producing signals identical in magnitude, but
out of phase by 180°. Consequently, the differential gain for the Audio Amplifier is
AVD = 2 *(Rf/Ri)
(1)
By driving the load differentially through outputs OUT A and OUT B, an amplifier configuration commonly referred
to as “bridged mode” is established. Bridged mode operation is different from the classic single-ended amplifier
configuration where one side of the load is connected to ground.
A bridge amplifier design has a few distinct advantages over the single-ended configuration. It provides
differential drive to the load, thus doubling the output swing for a specified supply voltage. Four times the output
power is possible as compared to a single-ended amplifier under the same conditions. This increase in attainable
output power assumes that the amplifier is not current limited or clipped. In order to choose an amplifier’s closedloop gain without causing excessive clipping, please refer to the Audio Power Amplifier Design section.
The bridge configuration also creates a second advantage over single-ended amplifiers. Since the differential
outputs, OUT A and OUT B, are biased at half-supply, no net DC voltage exists across the load. This eliminates
the need for an output coupling capacitor which is required in a single supply, single-ended amplifier
configuration. Without an output coupling capacitor, the half-supply bias across the load would result in both
increased internal IC power dissipation and also possible loudspeaker damage.
OUTPUT TRANSIENT ('CLICK AND POPS') ELIMINATED
The LM4953 contains advanced circuitry that virtually eliminates output transients ('clicks and pops'). This
circuitry prevents all traces of transients when the supply voltage is first applied or when the part resumes
operation after coming out of shutdown mode.
POWER DISSIPATION
Power dissipation is a major concern when using any power amplifier and must be thoroughly understood to
ensure a successful design. Equation 2 states the maximum power dissipation point for a single-ended amplifier
operating at a given supply voltage and driving a specified output load.
PDMAX = (VDD) 2 / (2π2ZL)
(2)
Since the LM4953 has two operational amplifiers in one package, the maximum internal power dissipation point
is twice that of the number which results from Equation 2. Even with large internal power dissipation, the LM4953
does not require heat sinking over a large range of ambient temperatures. The maximum power dissipation point
obtained must not be greater than the power dissipation that results from Equation 3:
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PDMAX = (TJMAX - TA) / (θJA)
(3)
Depending on the ambient temperature, TA, of the system surroundings, Equation 3 can be used to find the
maximum internal power dissipation supported by the IC packaging. If the result of Equation 2 is greater than
that of Equation 3, then either the supply voltage must be decreased, the load impedance increased or TA
reduced. Power dissipation is a function of output power and thus, if typical operation is not around the maximum
power dissipation point, the ambient temperature may be increased accordingly.
POWER SUPPLY BYPASSING
As with any power amplifier, proper supply bypassing is critical for low noise performance and high power supply
rejection. Applications that employ a 3V power supply typically use a 4.7µF capacitor in parallel with a 0.1µF
ceramic filter capacitor to stabilize the power supply's output, reduce noise on the supply line, and improve the
supply's transient response. Keep the length of leads and traces that connect capacitors between the LM4953's
power supply pin and ground as short as possible.
AUTOMATIC STANDBY MODE
The LM4953 features Automatic Standby Mode circuitry (patent pending). In the absence of an input signal, after
approximately 3 seconds, the LM4953 goes into low current standby mode. The LM4953 recovers into full power
operating mode immediately after a signal, which is greater than the input threshold voltage, is applied to either
the left or right input pins. The input threshold voltage is not a static value, as the supply voltage increases, the
input threshold voltage decreases. This feature reduces power supply current consumption in battery operated
applications.
To ensure correct operation of Automatic Standby Mode, proper layout techniques should be implemented.
Separating PGND and SGND can help reduce noise entering the LM4953 in noisy environments. It is also
important to use correct power off sequencing. The device should be in shutdown and then powered off in order
to ensure proper functionality of the Auto-Standby feature. While Automatic Standby Mode reduces power
consumption very effectively during silent periods, maximum power saving is achieved by putting the device into
shutdown when it is not in use.
MICRO POWER SHUTDOWN
The voltage applied to the SD controls the LM4953’s shutdown function. When active, the LM4953’s micropower
shutdown feature turns off the amplifiers’ bias circuitry, reducing the supply current. The trigger point is
0.3*CPVDD for a logic-low level, and 0.7*CPVDD for logic-high level. The low 0.01µA (typ) shutdown current is
achieved by applying a voltage that is as near as ground a possible to the SD pins. A voltage that is higher than
ground may increase the shutdown current.
There are a few ways to control the micro-power shutdown. These include using a single-pole, single-throw
switch, a microprocessor, or a microcontroller. When using a switch, connect an external 100kΩ pull-up resistor
between the SD pins and VDD. Connect the switch between the SD pins and ground. Select normal amplifier
operation by opening the switch. Closing the switch connects the SD pins to ground, activating micro-power
shutdown. The switch and resistor ensure that the SD pins will not float. This prevents unwanted state changes.
In a system with a microprocessor or microcontroller, use a digital output to apply the control voltage to the SD
pins. Driving the SD pins with active circuitry eliminates the pull-up resistor.
EXPOSED-DAP CONSIDERATIONS
It is essential that the exposed Die Attach Paddle (DAP), for the LM4953, is NOT connected to GND. For optimal
operation it should be connected to AVss and VCP-OUT (Pins 6 and 8).
SELECTING PROPER EXTERNAL COMPONENTS
Optimizing the LM4953's performance requires properly selecting external components. Though the LM4953
operates well when using external components with wide tolerances, best performance is achieved by optimizing
component values.
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Charge Pump Capacitor Selection
Use low ESR (equivalent series resistance) (<100mΩ) ceramic capacitors with an X7R dielectric for best
performance. Low ESR capacitors keep the charge pump output impedance to a minimum, extending the
headroom on the negative supply. Higher ESR capacitors result in reduced output power from the audio
amplifiers.
Charge pump load regulation and output impedance are affected by the value of the flying capacitor (C1). A
larger valued C1 (up to 3.3uF) improves load regulation and minimizes charge pump output resistance. Beyond
3.3uF, the switch-on resistance dominates the output impedance for capacitor values above 2.2uF.
The output ripple is affected by the value and ESR of the output capacitor (C2). Larger capacitors reduce output
ripple on the negative power supply. Lower ESR capacitors minimize the output ripple and reduce the output
impedance of the charge pump.
The LM4953 charge pump design is optimized for 2.2uF, low ESR, ceramic, flying, and output capacitors.
Input Capacitor Value Selection
Amplifying the lowest audio frequencies requires high value input coupling capacitors (Ci in Figure 1). A high
value capacitor can be expensive and may compromise space efficiency in portable designs. In many cases,
however, the speakers used in portable systems, whether internal or external, have little ability to reproduce
signals below 150Hz. Applications using speakers with this limited frequency response reap little improvement by
using high value input and output capacitors.
Besides affecting system cost and size, Ci has an effect on the LM4953's click and pop performance. The
magnitude of the pop is directly proportional to the input capacitor's size. Thus, pops can be minimized by
selecting an input capacitor value that is no higher than necessary to meet the desired −3dB frequency.
As shown in Figure 1, the internal input resistor, Ri and the input capacitor, Ci, produce a -3dB high pass filter
cutoff frequency that is found using Equation 4. Conventional headphone amplifiers require output capacitors;
Equation 4 can be used, along with the value of RL, to determine towards the value of output capacitor needed to
produce a –3dB high pass filter cutoff frequency.
fi-3dB = 1 / 2πRiCi
(4)
Also, careful consideration must be taken in selecting a certain type of capacitor to be used in the system.
Different types of capacitors (tantalum, electrolytic, ceramic) have unique performance characteristics and may
affect overall system performance. (See the section entitled Charge Pump Capacitor Selection.)
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LM4953 DEMO BOARD ARTWORK
12
Figure 16. Top Layer
Figure 17. Mid Layer 1
Figure 18. Mid Layer 2
Figure 19. Bottom Layer
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Revision History
Rev
Date
Description
1.0
2/18/05
Started D/S by copying LM4926 (DS201161).
1.2
9/13/05
Added the Typ Perf curves and Application Info
section.
1.3
9/14/05
Added more Typ Perf curves.
First WEB release on the D/S.
1.4
9/19/05
Fixed some typo, then re-released D/S to the
WEB.
1.5
11/11/05
Added the WSON boards, then re-released D/S
to the WEB... not released on this date..
1.6
11/14/05
Added the WSON boards, then re-released D/S
to the WEB (per Nisha).
1.7
11/15/05
Text edit.
1.8
12/21/05
Added the EXPOSED-DAP
CONSIDERATIONS (Application Info section),
then re-released D/S to the WEB.
1.9
2/01/06
Edited 20142168 (Typ Appl ckt)..., then rereleased D/S to the WEB.
Copyright © 2005–2006, Texas Instruments Incorporated
Product Folder Links: LM4953 LM4953SDBD
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13
PACKAGE OPTION ADDENDUM
www.ti.com
24-Jan-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package Qty
Drawing
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Top-Side Markings
(3)
(4)
LM4953SD/NOPB
ACTIVE
WSON
NHK
14
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
L4953
LM4953SDX/NOPB
ACTIVE
WSON
NHK
14
4500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
L4953
(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)
Only one of markings shown within the brackets will appear on the physical 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
Samples
PACKAGE MATERIALS INFORMATION
www.ti.com
21-Mar-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM4953SD/NOPB
WSON
NHK
14
1000
178.0
12.4
3.3
4.3
1.0
8.0
12.0
Q1
LM4953SDX/NOPB
WSON
NHK
14
4500
330.0
12.4
3.3
4.3
1.0
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
21-Mar-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM4953SD/NOPB
WSON
NHK
14
1000
203.0
190.0
41.0
LM4953SDX/NOPB
WSON
NHK
14
4500
367.0
367.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
NHK0014A
SDA14A (Rev A)
www.ti.com
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