LM48860
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LM48860 Ground-Referenced, Ultra Low Noise, Fixed Gain
Stereo Headphone Amplifier
Check for Samples: LM48860
1FEATURES DESCRIPTION
The LM48860 is a ground referenced, fixed-gain
2• Fixed Logic Levels with Supply Voltage audio power amplifier capable of delivering 40mW per
• Ground Referenced Outputs channel of continuous average power into a 16Ω
• High PSRR single-ended load with less than 1% THD+N from a
3V power supply.
• Available in Space-Saving DSBGA Package
• Ultra Low Current Shutdown Mode The LM48860 features a new circuit technology that
utilizes a charge pump to generate a negative
• Improved Pop & Click Circuitry Eliminates reference voltage. This allows the outputs to be
Noises During Turn-On and Turn-Off biased about ground, thereby eliminating output-
Transitions coupling capacitors typically used with normal single-
• No Output Coupling Capacitors, Snubber ended loads.
Networks, Bootstrap Capacitors, or Gain- Boomer audio power amplifiers were designed
Setting Resistors Required specifically to provide high quality output power with a
• Shutdown Either Channel Independently minimal amount of external components. The
LM48860 does not require output coupling capacitors
APPLICATIONS or bootstrap capacitors, and therefore is ideally suited
for mobile phone and other low voltage applications
• Mobile Phones where minimal power consumption is a primary
• MP3 Players requirement.
• PDAs The LM48860 features a low-power consumption
• Portable Electronic Devices shutdown mode selectable for either channel
separately. This is accomplished by driving either the
• Notebook PCs SD_RC (Shutdown Right Channel) or SD_LC
(Shutdown Left Channel) (or both) pins with logic low,
KEY SPECIFICATIONS depending on which channel is desired shutdown.
• PSRR at 217Hz (VDD = 3.0V): 80dB (typ) Additionally, the LM48860 features an internal
• Stereo Power Output at VDD = 3V, RL= 16Ω,thermal shutdown protection mechanism.
THD+N = 1%: 40mW (typ) The LM48860 contains advanced pop & click circuitry
• Shutdown Current 0.1μA (typ) that eliminates noises which would otherwise occur
during turn-on and turn-off transitions.
• Internal Fixed Gain: 1.5V/V (typ)
• Operating Voltage: 2.0V to 5.5V The LM48860 has an internal fixed gain of 1.5V/V.
1Please 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.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2008–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
D
C
B
ALIN
ROUT
SGND
CCP-
VDD
LOUT
RIN
12 3
CCP+
VSS(CP)
PGND
SD_RC
SD_LC
4.7 PF0.1 PF ceramic
-
+
30 k:
20 k:
C6
C5
Shutdown
Control Click/Pop
Suppression
Charge
Pump
-
+
30 k:
SD_RC
20 k:
C3
2.2 PF
1 PF
VIN1
+
C1
1 PF
VIN2
+
C2
C4
2.2 PF
+
VDD
Headphone
Jack
SD_LC
VDD
RIN ROUT
VSS(CP)
LIN
LOUT
CCP+
CCP-
SGND SGND
Ri
Ri
LM48860
SNAS398D –JANUARY 2008–REVISED MAY 2013
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Typical Application
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagram
Figure 2. DSBGA - Top View
See YZR0012 Package
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PIN DESCRIPTIONS
Pin Name Function
A1 RIN Right Channel Input
A2 SGND Signal Ground
A3 LIN Left Channel Input
B1 ROUT Right Channel Output
B2 SD_LC Active Low Shutdown, Left Channel
B3 LOUT Left Channel Output
C1 VSS(CP) Charge Pump Voltage Output
C2 SD_RC Active-Low Shutdown, Right Channel
C3 VDD Supply Voltage
D1 CCP- Negative Terminal - Charge Pump Flying Capacitor
D2 PGND Power Ground
D3 CCP+ Positive Terminal - Charge Pump Flying Capacitor
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)
Supply Voltage 6.0V
Storage Temperature −65°C to +150°C
Input Voltage -0.3V to VDD
Power Dissipation(3) Internally Limited
ESD Rating(4) 2000V
ESD Rating(5) 200V
Junction Temperature 150°C
Thermal Resistance
θJA (typ) DSBGA 59.3°C/W
(1) The Electrical Characteristics tables list ensure specifications under the listed Recommended Operating Conditions except as otherwise
modified or specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and are not
specified.
(2) If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
(3) 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 LM48860, see power derating curves for additional information.
(4) Human body model, applicable std. JESD22-A114C.
(5) Machine model, applicable std. JESD22-A115-A.
Operating Ratings
Temperature Range
TMIN ≤TA≤TMAX −40°C ≤TA≤85°C
Supply Voltage (VDD) 2.0V ≤VDD ≤5.5V
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Electrical Characteristics VDD = 3V (1)(2)
The following specifications apply for VDD = 3V and 16Ωload unless otherwise specified. Limits apply to TA= 25°C.
LM48860 Units
Symbol Parameter Conditions (Limits)
Typical(3) Limit(4)
VDD = 3.0V,
VIN = 0V, inputs terminated 4 5.5 mA (max)
both channels enabled
Quiescent Power Supply Current
IDD Full Power Mode VDD = 5.0V,
VIN = 0V, inputs terminated 4.2 mA
both channels enabled
SD_LC = SD_RC= GND 0.1 1 µA (max)
ISD Shutdown Current SD_LC = SD_RC= GND, 0.1 1 µA (max)
VDD = 5.0V
VOS Output Offset Voltage RL= 32Ω, VIN = 0V 0.7 5.5 mV (max)
AVVoltage Gain –1.5 V/V
ΔAVChannel-to-channel Gain 1 %
Matching 15 kΩ(min)
RIN Input Resistance 20 25 kΩ(max)
THD+N = 1% (max); f = 1kHz, 40 35 mW (min)
RL= 16Ω, (two channels in phase)
POOutput Power THD+N = 1% (max); f = 1kHz, 50 40 mW (min)
RL= 32Ω, (two channels in phase)
PO= 20mW, f = 1kHz, RL= 16Ω0.025 %
(two channels in phase)
THD+N Total Harmonic Distortion + Noise PO= 25mW, f = 1kHz, RL= 32Ω0.014 %
(two channels in phase)
VRIPPLE = 200mVPP, Input Referred
f = 217Hz 80 73 dB (min)
Power Supply Rejection Ratio
PSRR Full Power Mode f = 1kHz 75 dB
f = 20kHz 60 dB
RL= 32Ω, POUT = 50mW,
SNR Signal-to-Noise Ratio f = 1kHz, BW = 20Hz to 22kHz, 105 dB
A-weighted
VIH Shutdown Input Voltage High VDD = 2.0V to 5.5V 1.2 V (min)
VIL Shutdown Input Voltage Low VDD = 2.0V to 5.5V 0.45 V (max)
RL= 16Ω, PO= 1.6mW,
XTALK Crosstalk 75 dB
f = 1kHz
∈OS Output Noise A-weighted filter, VIN = 0V 8 μV
VSD = GND
Input Terminated
ZOUT Output Impedance Input not terminated 30 20 kΩ(min)
SD_LC = SD_RC = GND 30 kΩ
ILInput Leakage ±0.1 nA
(1) “Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the Recommended Operating Conditions is not implied. The Recommended Operating
Conditions indicate conditions at which the device is functional and the device should not be operated beyond such conditions. All
voltages are measured with respect to the ground pin, unless otherwise specified.
(2) The Electrical Characteristics tables list ensure specifications under the listed Recommended Operating Conditions except as otherwise
modified or specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and are not
specified.
(3) Typical values represent most likely parametric norms at TA= +25ºC, and at the Recommended Operation Conditions at the time of
product characterization and are not specified.
(4) Datasheet min/max specification limits are ensured by test or statistical analysis.
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External Components Description
(Figure 1)
Components Functional Description
Input coupling capacitor which blocks the DC voltage at the amplifier’s input terminals. Also creates a high pass-pass
1. C1filter with Riat fC= 1/(2RiC1). Refer to the section Proper Selection of External Components, for an explanation of how
to determine the value of C1.
Input coupling capacitor which blocks the DC voltage at the amplifier’s input terminals. Also creates a high pass-pass
2. C2filter with Riat fC= 1/(2RiC2). Refer to the Power Supply Bypassing section for an explanation of how to determine the
value of C2.
3. C3Output capacitor. Low ESR ceramic capacitor (≤100mΩ)
4. C4Flying capacitor. Low ESR ceramic capacitor (≤100mΩ)
Tantalum capacitor. Supply bypass capacitor which provides power supply filtering. Refer to the Power Supply
5. C5Bypassing section for information concerning proper placement and selection of the supply bypass capacitor.
Ceramic capacitor. Supply bypass capacitor which provides power supply filtering. Refer to the Power Supply
6. C6Bypassing section for information concerning proper placement and selection of the supply bypass capacitor.
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OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 80
70
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 200
0.1
1
20 40 60 100
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
LM48860
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Typical Performance Characteristics
THD+N vs Output Power THD+N vs Output Power
VDD = 3V, RL= 16ΩVDD = 3V, RL= 16Ω, f = 1kHz
f = 1kHz, 22kHz BW, one channel enabled 22kHz BW, two channels in phase
Figure 3. Figure 4.
THD+N vs Output Power THD+N vs Output Power
VDD = 3V, RL= 32ΩVDD = 3V, RL= 32Ω, f = 1kHz
f = 1kHz, 22kHz BW, one channel enabled 22kHz BW, two channels in phase
Figure 5. Figure 6.
THD+N vs Output Power THD+N vs Output Power
VDD = 3.6V, RL= 16ΩVDD = 3.6V, RL= 16Ω, f = 1kHz
f = 1kHz, 22kHz BW, one channel enabled 22kHz BW, two channels in phase
Figure 7. Figure 8.
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OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 200
0.1
1
20 40 60 100
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 200
0.1
1
20 40 60 100
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
OUTPUT POWER (mW)
THD+N (%)
0.01
10
10 100
0.1
1
20 30 40 50 60 8070
LM48860
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Typical Performance Characteristics (continued)
THD+N vs Output Power THD+N vs Output Power
VDD = 3.6V, RL= 32ΩVDD = 3.6V, RL= 32Ω, f = 1kHz
f = 1kHz, 22kHz BW, one channel enabled 22kHz BW, two channels in phase
Figure 9. Figure 10.
THD+N vs Output Power THD+N vs Output Power
VDD = 4.2V, RL= 16ΩVDD = 4.2V, RL= 16Ω, f = 1kHz
f = 1kHz, 22kHz BW, one channel enabled 22kHz BW, two channels in phase
Figure 11. Figure 12.
THD+N vs Output Power THD+N vs Output Power
VDD = 4.2V, RL= 32ΩVDD = 4.2V, RL= 32Ω, f = 1kHz
f = 1kHz, 22kHz BW, one channel enabled 22kHz BW, two channels in phase
Figure 13. Figure 14.
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FREQUENCY (Hz)
THD+N (%)
0.001
10
0.1
1
20 20k2k
200
0.01
FREQUENCY (Hz)
THD+N (%)
0.001
10
0.1
1
20 20k2k
200
0.01
FREQUENCY (Hz)
THD+N (%)
0.001
10
0.1
1
20 20k2k200
0.01
FREQUENCY (Hz)
THD+N (%)
0.001
10
0.1
1
20 20k2k200
0.01
FREQUENCY (Hz)
THD+N (%)
0.001
10
0.1
1
20 20k2k200
0.01
FREQUENCY (Hz)
THD+N (%)
0.001
10
0.1
1
20 20k2k
200
0.01
LM48860
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Typical Performance Characteristics (continued)
THD+N vs Frequency THD+N vs Frequency
VDD = 3V, RL= 16ΩVDD = 3V, RL= 32Ω
PO= 20mW, 22kHz BW PO= 20mW, 22kHz BW
Figure 15. Figure 16.
THD+N vs Frequency THD+N vs Frequency
VDD = 3.6V, RL= 16ΩVDD = 3.6V, RL= 32Ω
PO= 30mW, 22kHz BW PO= 30mW, 22kHz BW
Figure 17. Figure 18.
THD+N vs Frequency THD+N vs Frequency
VDD = 4.2V, RL= 16ΩVDD = 4.2V, RL= 32Ω
PO= 30mW, 22kHz BW PO= 30mW, 22kHz BW
Figure 19. Figure 20.
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PSRR (dB)
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
FREQUENCY (Hz)
20k200 2k20
PSRR (dB)
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
FREQUENCY (Hz)
20k200 2k20
PSRR (dB)
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
FREQUENCY (Hz)
20k200 2k20
PSRR (dB)
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
FREQUENCY (Hz)
20k200 2k20
PSRR (dB)
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
FREQUENCY (Hz)
20k200 2k20
PSRR (dB)
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
FREQUENCY (Hz)
20k200 2k20
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Typical Performance Characteristics (continued)
PSRR vs Frequency PSRR vs Frequency
VDD = 3V, RL= 16ΩVDD = 3V, RL= 32Ω
VRIPPLE = 200mVPP VRIPPLE = 200mVPP
Figure 21. Figure 22.
PSRR vs Frequency PSRR vs Frequency
VDD = 3.6V, RL= 16ΩVDD = 3.6V, RL= 32Ω
VRIPPLE = 200mVPP VRIPPLE = 200mVPP
Figure 23. Figure 24.
PSRR vs Frequency PSRR vs Frequency
VDD = 4.2V, RL= 16ΩVDD = 4.2V, RL= 32Ω
VRIPPLE = 200mVPP VRIPPLE = 200mVPP
Figure 25. Figure 26.
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400
0 30 40 50 60 70 80
0
50
100
150
200
250
300
350
20
10
OUTPUT POWER/CHANNEL (mW)
POWER DISSIPATION (mW)
POWER DISSIPATION (mW)
700
0 120
0
200
300
400
500
600
20 40 60 80 100
100
OUTPUT POWER/CHANNEL (mW)
OUTPUT POWER/CHANNEL (mW)
POWER DISSIPATION (mW)
300
0 70
0
100
150
200
250
50
10 20 30 40 50 60
OUTPUT POWER/ CHANNEL (mW)
POWER DISSIPATION (mW)
200
0 70
0
25
50
75
100
125
150
175
10 20 30 40 50 60
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
0
120
2.0 3.0 3.5 4.0 4.5 5.0 5.5
20
40
60
80
100 THD+N = 10%
THD+N = 1%
2.5
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
0
70
2.0 3.0 3.5 4.0 4.5 5.0 5.5
20
30
40
50
60
10
2.5
THD+N = 10%
THD+N = 1%
LM48860
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Typical Performance Characteristics (continued)
Output Power vs Supply Voltage Output Power vs Supply Voltage
RL= 16Ω, f = 1kHz, 22kHz BW RL= 32Ω, f = 1kHz, 22kHz BW
Figure 27. Figure 28.
Power Dissipation vs Output Power Power Dissipation vs Output Power
VDD = 3V, RL= 16Ω, f = 1kHz VDD = 3V, RL= 32Ω, f = 1kHz
Figure 29. Figure 30.
Power Dissipation vs Output Power Power Dissipation vs Output Power
VDD = 5V, RL= 16Ω, f = 1kHz VDD = 5V, RL= 32Ω, f = 1kHz
Figure 31. Figure 32.
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150
0 400
125
POWER DISSIPATION (mW)
AMBIENT TEMPERATURE (°C)
130
135
140
145
50 100 150 200 250 300 350
150
0 200
135
POWER DISSIPATION (mW)
AMBIENT TEMPERATURE (°C)
140
145
20 40 60 80 100 120 140 160 180
150
100 700
100
POWER DISSIPATION (mW)
AMBIENT TEMPERATURE (°C)
110
120
130
140
200 300 400 500 600
0
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
3.00
3.25
3.50
3.75
4.00
2.0 3.0 3.5 4.0 4.5 5.0 5.5
2.5
150
0 300
130
135
140
145
POWER DISSIPATION (mW)
AMBIENT TEMPERATURE (°C)
50 100 150 200 250
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Typical Performance Characteristics (continued)
Supply Current vs Supply Voltage Power Derating Curve
VIN = GND, No Load VDD = 3V, RL= 16Ω
Figure 33. Figure 34.
Power Derating Curve Power Derating Curve
VDD = 3V, RL= 32ΩVDD = 5V, RL= 16Ω
Figure 35. Figure 36.
Power Derating Curve
VDD = 5V, RL= 32Ω
Figure 37.
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APPLICATION INFORMATION
SUPPLY VOLTAGE SEQUENCING
It is a good general practice to first apply the supply voltage to a CMOS device before any other signal or supply
on other pins. This is also true for the LM48860 audio amplifier which is a CMOS device.
Before applying any signal to the inputs or shutdown pins of the LM48860, it is important to apply a supply
voltage to the VDD pins. After the device has been powered, signals may be applied to the shutdown pins (see
MICRO POWER SHUTDOWN) and input pins.
ELIMINATING THE OUTPUT COUPLING CAPACITOR
The LM48860 features a low noise inverting charge pump that generates an internal negative supply voltage.
This allows the outputs of the LM48860 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
LM48860 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 LM48860 when compared to a traditional headphone amplifier operating from the
same supply voltage.
OUTPUT TRANSIENT ('CLICK AND POPS') ELIMINATED
The LM48860 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.
AMPLIFIER CONFIGURATION EXPLANATION
As shown in Figure 1, the LM48860 has two internal operational amplifiers. The two amplifiers have internally
configured gain.
Since this is an output ground-referenced amplifier, the LM48860 does not require output coupling capacitors.
POWER DISSIPATION
From the graph (THD+N vs Output Power , VDD = 3V, RL= 16Ω, f = 1kHz, 22kH BW, two channels in phase,
page 6) assuming a 3V power supply and a 16Ωload, the maximum power dissipation point and thus the
maximum package dissipation point is 281mW. The maximum power dissipation point obtained must not be
greater than the power dissipation that results from Equation 1.
PDMAX = (TJMAX - TA) / (θJA) (1)
For the DSBGA package θJA = 59.3°C/W. TJMAX = 150°C for the LM48860. Depending on the ambient
temperature, TA, of the system surroundings, Equation 1 can be used to find the maximum internal power
dissipation supported by the IC packaging. If the maximum power dissipation from the graph is greater than that
of Equation 1, then either the supply voltage must be decreased, the load impedance increased or TAreduced
(see power derating curves). For the application of a 5V power supply, with a 16Ωload, the maximum ambient
temperature possible without violating the maximum junction temperature is approximately 110°C provided that
device operation is around the maximum power dissipation point. 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.
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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 LM48860's
power supply pin and ground as short as possible.
MICRO POWER SHUTDOWN
The voltage applied to the SD_LC (shutdown left channel) pin and the SD_RC (shutdown right channel) pin
controls the LM48860’s shutdown function. When active, the LM48860’s micropower shutdown feature turns off
the amplifiers’ bias circuitry, reducing the supply current. The trigger point is 0.45V for a logic-low level, and 1.2V
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_LC/SD_RC pins. A voltage that is higher than ground may increase the shutdown
current. Do not let SD_LC/SD_RC float, connect either to high or low.
SELECTING PROPER EXTERNAL COMPONENTS
Optimizing the LM48860's performance requires properly selecting external components. Though the LM48860
operates well when using external components with wide tolerances, best performance is achieved by optimizing
component values.
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 (C4). A
larger valued C4 (up to 3.3uF) improves load regulation and minimizes charge pump output resistance. Beyond
3.3uF, the switch-on resistance dominates the output impedance.
The output ripple is affected by the value and ESR of the output capacitor (C3). 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 LM48860 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 (C1 and C2 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.
As shown in Figure 1, the internal input resistor, Riand the input capacitors, C1 and C2, produce a -3dB high-
pass filter cutoff frequency that is found using Equation 2.
fi-3dB = 1 / 2πRINC (Hz) (2)
The value of RIN can be found in the Electrical Characteristics tables.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LM48860
LM48860
SNAS398D –JANUARY 2008–REVISED MAY 2013
www.ti.com
REVISION HISTORY
Rev Date Description
1.0 01/16/08 Initial release.
1.01 01/29/08 Text edits.
1.02 02/14/08 Fixed typos (x-axis) on few curves.
1.03 10/17/08 Edited the X1 and X2 limits under the
Physical Dimension section.
D 05/02/2013 Changed layout of National Data Sheet to TI
format.
16 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LM48860
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead finish/
Ball material
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LM48860TL/NOPB ACTIVE DSBGA YZR 12 250 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 84 GJ7
LM48860TLX/NOPB ACTIVE DSBGA YZR 12 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 84 GJ7
(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.
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 2
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LM48860TL/NOPB DSBGA YZR 12 250 178.0 8.4 1.68 2.13 0.76 4.0 8.0 Q1
LM48860TLX/NOPB DSBGA YZR 12 3000 178.0 8.4 1.68 2.13 0.76 4.0 8.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 8-May-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM48860TL/NOPB DSBGA YZR 12 250 210.0 185.0 35.0
LM48860TLX/NOPB DSBGA YZR 12 3000 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 8-May-2013
Pack Materials-Page 2
MECHANICAL DATA
YZR0012xxx
www.ti.com
TLA12XXX (Rev C)
0.600±0.075 D
E
A
. All linear dimensions are in millimeters. Dimensioning and tolerancing per ASME Y14.5M-1994.
B. This drawing is subject to change without notice.
4215049/A 12/12
NOTES:
D: Max =
E: Max =
2.014 mm, Min =
1.514 mm, Min =
1.954 mm
1.454 mm
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