LM48820
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SNAS370B –MAY 2007–REVISED MAY 2013
LM48820 Ground-Referenced, Ultra Low Noise, Fixed
Gain, 95mW Stereo Headphone Amplifier
Check for Samples: LM48820
1FEATURES DESCRIPTION
The LM48820 is a ground referenced, fixed-gain
2• Available in Space Saving 0.4mm Pitch audio power amplifier capable of delivering 95mW of
DSBGA Package continuous average power into a 16Ωsingle-ended
• Fixed Logic Levels load, with less than 1% THD+N from a 3V power
• Ground Referenced Outputs supply.
• High PSRR The LM48820 features a new circuit technology that
utilizes a charge pump to generate a negative
• Ultra Low Current Shutdown Mode reference voltage. This allows the outputs to be
• Improved Pop and Click Circuitry Eliminates biased about ground, thereby eliminating output-
Noises During Turn-On and Turn-Off coupling capacitors typically used with normal single-
Transitions ended loads.
• No Output Coupling Capacitors, Snubber Boomer audio power amplifiers were designed
Networks, Bootstrap Capacitors, or Gain- specifically to provide high quality output power with a
Setting Resistors Required minimal number of external components. The
• Shutdown Either Channel Independently LM48820 does not require output coupling capacitors
or bootstrap capacitors, and therefore is ideally suited
• Soft Start Feature Reduces Start up Transient for mobile phone and other portable applications.
Current The LM48820 features a low-power consumption
APPLICATIONS shutdown mode selectable for each channel and a
soft start function that reduces start-up current
• Mobile Phones transients. Additionally, the LM48820 features an
• MP3 Players internal thermal shutdown protection mechanism.
• PDAs The LM48820 contains advanced pop and click
• Portable electronic devices circuitry that eliminates noises which would otherwise
• Notebook PCs occur during turn-on and turn-off transitions.
The LM48820 has an internal fixed gain of 1.5V/V.
KEY SPECIFICATIONS
• Improved PSRR at 217Hz: 80dB (typ)
• Power Output at VDD = 3V, RL = 16Ω, THD+N =
1%: 95mW (typ)
• Shutdown Current: 0.05μA (typ)
• Internal Fixed Gain: 1.5V/V (typ)
• Wide Operating Voltage Range: 1.6V to 4.5V
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 © 2007–2013, 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.
1 2
A
3 4
B
C
D
RIN SGND CPVDD CCP+
PGNDSD_LC
SD_RC
LIN ROUT CCP-
AVDD LOUT -AVDD VCP_OUT
Ri
4.7 PF0.1 PF ceramic
-
+
30 k:
20 k:
CS1
Rf
Shutdown
Control
Click/Pop
Suppression
Charge
Pump
-
+
30 k:
Rf
SD_LC
SD_RC
Ri
20 k:
CSS
2.2 PF
ROUT
SGND
PGND
0.39 PF
VINL
+
CINL
0.39 PF
VINR
+
CINR
CC
2.2 PF
+
CPVDD
Headphone
Jack
AVDD CPVDD
CS2
LOUT
LIN
CCP+
CCP-
RIN
VCP_OUT -AVDD
LM48820
SNAS370B –MAY 2007–REVISED MAY 2013
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Typical Application
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagrams
Figure 2. DSBGA Package
Top View
Package Number YFR0014AAA
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Figure 3. YFR0014 Package View
PIN DESCRIPTIONS
Pin Name Function
A1 RIN Right Channel Input
A2 SGND Signal Ground
A3 CPVDD Charge Pump Power Supply
A4 CCP+ Positive Terminal - Charge Pump Flying Capacitor
B1 SD_RC Active-Low Shutdown, Right Channel
B2 SD_LC Active-Low Shutdown, Left Channel
B4 PGND Power Ground
C1 LIN Left Channel Input
C2 ROUT Right Channel Output
C4 CCP- Negative Terminal - Charge Pump Flying Capacitor
D1 AVDD Positive Power Supply - Amplifier
D2 LOUT Left Channel Output
D3 -AVDD Negative Power Supply - Amplifier
D4 VCP_OUT Charge Pump Power Output
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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 4.75V
Storage Temperature −65°C to +150°C
Input Voltage -0.3V to VDD + 0.3V
Power Dissipation (4) Internally Limited
ESD Susceptibility (5) 2000V
ESD Susceptibility (6) 200V
Junction Temperature 150°C
Thermal Resistance
θJA (7) 86°C/W (typ)
(1) All voltages are measured with respect to the GND 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 that specify performance limits. This assumes that the device is within the Operating
Ratings. Specifications are not ensured for parameters where no limit is given; however, the typical value is a good indication of device
performance.
(3) If Military/Aerospace specified devices are required, please contact the 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. See Typical Performance Characteristics for more information
(5) Human body model, 100pF discharged through a 1.5kΩresistor.
(6) Machine Model, 220pF - 240pF discharged through all pins.
(7) θJA value is measured with the device mounted on a PCB with a 3” x 1.5”, 1oz copper heatsink.
Operating Ratings
Temperature Range
TMIN ≤TA≤TMAX −40°C ≤TA≤85°C
Supply Voltage (VDD) 1.6V ≤VDD ≤4.5V
Electrical Characteristics VDD = 3V (1)(2)
The following specifications apply for VDD = 3V, 16Ωload, and the conditions shown in “Typical Audio Amplifier Application
Circuit” (see Figure 1) unless otherwise specified. Limits apply to TA= 25°C. LM48820 Units
Symbol Parameter Conditions Typical Limit (Limits)
(3) (4) (5)
VIN = 0V, inputs terminated 4.7 5.5 mA (max)
both channels enabled
Quiescent Power Supply Current
IDD Full Power Mode VIN = 0V, inputs terminated 3 mA (max)
one channel enabled
ISD Shutdown Current SD_LC = SD_RC = GND 0.05 2 µA (max)
VOS Output Offset Voltage RL= 32Ω, VIN = 0V 1 5 mV (max)
AVVoltage Gain –1.5 V/V
ΔAVGain Match 1 %
(1) All voltages are measured with respect to the GND 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 that specify performance limits. This assumes that the device is within the Operating
Ratings. Specifications are not ensured for parameters where no limit is given; however, the typical value is a good indication of device
performance.
(3) Typicals are measured at 25°C and represent the parametric norm.
(4) Limits are specified to AOQL (Average Outgoing Quality Level).
(5) Data sheet min and max specification limits are specified by design, test, or statistical analysis.
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Electrical Characteristics VDD = 3V (1)(2) (continued)
The following specifications apply for VDD = 3V, 16Ωload, and the conditions shown in “Typical Audio Amplifier Application
Circuit” (see Figure 1) unless otherwise specified. Limits apply to TA= 25°C. LM48820 Units
Symbol Parameter Conditions Typical Limit (Limits)
(3) (4) (5)
15 kΩ(min)
RIN Input Resistance 20 25 kΩ(max)
THD+N = 1% (max); f = 1kHz, 95 mW
one channel
THD+N = 1% (max); f = 1kHz, 80 mW
RL= 32Ω, one channel
POOutput Power THD+N = 1% (max); f = 1kHz, 50 40 mW (min)
two channels in phase
THD+N = 1% (max); f = 1kHz, 55 45 mW (min)
RL= 32Ω, two channels in phase
PO= 60mW, f = 1kHz, 0.01 %
single channel
THD+N Total Harmonic Distortion + Noise PO= 50mW, f = 1kHz, RL= 32Ω0.007 %
single channel
VRIPPLE = 200mVP-P, Input Referred
Power Supply Rejection Ratio f = 217Hz 80 dB
PSRR Full Power Mode f = 1kHz 75 dB
f = 20kHz 58 dB
RL= 32Ω, PO= 20mW,
SNR Signal-to-Noise Ratio (A-weighted) 100 dB
f = 1kHz, BW = 20Hz to 22kHz
VIH Shutdown Input Voltage High VDD = 1.8V to 4.2V 1.2 V (min)
VIL Shutdown Input Voltage Low VDD = 1.8V to 4.2V 0.45 V (max)
XTALK Crosstalk PO= 1.6mW, f = 1kHz 70 dB
SD_LC = SD_RC = GND
ZOUT Output Impedance Input Terminated 30 25 kΩ(min)
Input not terminated 30
SD_LC = SD_RC = GND
ZOUT Output Impedance –500mV ≤VOUT ≤VDD +500mV 8 2 kΩ(min)
(6)
ILInput Leakage ±0.1 nA
(6) VOUT refers to signal applied to the LM48820 outputs.
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 filter
1. CINR/INL with Riat fC= 1/(2πRiCIN). Refer to the section SELECTING PROPER EXTERNAL COMPONENTS, for an explanation
of how to determine the value of Ci.
2 CCFlying capacitor. Low ESR ceramic capacitor (≤100mΩ)
3. CSS Output capacitor. Low ESR ceramic capacitor (≤100mΩ)
Tantalum capacitor. Supply bypass capacitor which provides power supply filtering. Refer to the POWER SUPPLY
4. CS1 BYPASSING 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
5. CS2 BYPASSING section for information concerning proper placement and selection of the supply bypass capacitor.
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THD+N (%)
FREQUENCY (Hz)
1k20
1
10
10k
0.1
0.01
0.001 20k100
THD+N (%)
FREQUENCY (Hz)
1k20
1
10
10k
0.1
0.01
0.001 20k100
T
THD+N (%)
FREQUENCY (Hz)
1k20
1
10
10k
0.1
0.01
0.001 20k100
THD+N (%)
FREQUENCY (Hz)
1k20
1
10
10k
0.1
0.01
0.001 20k100
T
THD+N (%)
FREQUENCY (Hz)
1k20
1
10
10k
0.1
0.01
0.001 20k100
THD+N (%)
FREQUENCY (Hz)
1k20
1
10
10k
0.1
0.01
0.001 20k100
LM48820
SNAS370B –MAY 2007–REVISED MAY 2013
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Typical Performance Characteristics
THD+N vs Frequency THD+N vs Frequency
VDD = 1.6V, RL= 16Ω, Stereo, PO= 3mW VDD = 1.6V, RL= 32Ω, Stereo, PO= 3mW
Figure 4. Figure 5.
THD+N vs Frequency THD+N vs Frequency
VDD = 3V, RL= 16Ω, Stereo, PO= 25mW VDD = 3V, RL= 32Ω, Stereo, PO= 25mW
Figure 6. Figure 7.
THD+N vs Frequency THD+N vs Frequency
VDD = 3V, RL= 16Ω, One channel, PO= 60mW VDD = 3V, RL= 32Ω, One channel, PO= 50mW
Figure 8. Figure 9.
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THD+N (%)
OUTPUT POWER (mW)
1
10
100
1
0.1
0.01
10 500
0.001
f = 10 kHz
f = 20 Hz
f = 1 kHz
THD+N (%)
OUTPUT POWER (mW)
1
10
100
1
0.1
0.01
10 500
0.001
f = 10 kHz
f = 20 Hz
f = 1 kHz
THD+N (%)
OUTPUT POWER (mW)
1
10
100
1
0.1
0.01
10
0.001
f = 10 kHz
f = 20 Hz
f = 1 kHz
THD+N (%)
OUTPUT POWER (mW)
1
10
1001
0.1
0.01 10
f = 10 kHz
f = 20 Hz
f = 1 kHz
THD+N (%)
OUTPUT POWER (mW)
1
10
1001
0.1
0.01 10
f = 10 kHz
f = 20 Hz
f = 1 kHz
THD+N (%)
OUTPUT POWER (mW)
1
10
1001
0.1
0.01
10
0.001
f = 10 kHz
f = 20 Hz
f = 1 kHz
LM48820
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SNAS370B –MAY 2007–REVISED MAY 2013
Typical Performance Characteristics (continued)
THD+N vs Output Power THD+N vs Output Power
VDD = 1.6V, RL= 16Ω, One channel VDD = 1.6V, RL= 32Ω, One channel
Figure 10. Figure 11.
THD+N vs Output Power THD+N vs Output Power
VDD = 1.6V, RL= 16Ω, Stereo VDD = 1.6V, RL= 32Ω, Stereo
Figure 12. Figure 13.
THD+N vs Output Power THD+N vs Output Power
VDD = 3V, RL= 16Ω, One channel VDD = 3V, RL= 32Ω, One channel
Figure 14. Figure 15.
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500
OUTPUT POWER (mW)
POWER SUPPLY VOLTAGE (V)
5
01
400
300
0
100
200
32 4 6
THD+N = 1%
THD+N = 10%
250
OUTPUT POWER (mW)
POWER SUPPLY VOLTAGE (V)
5
01
200
150
0
50
100
32 4 6
300
THD+N = 1%
THD+N = 10%
500
OUTPUT POWER (mW)
POWER SUPPLY VOLTAGE (V)
5
01
400
300
0
100
200
32 4 6
THD+N = 1%
THD+N = 10%
250
OUTPUT POWER (mW)
POWER SUPPLY VOLTAGE (V)
5
01
200
150
0
50
100
32 4 6
300
THD+N = 1%
THD+N = 10%
THD+N (%)
OUTPUT POWER (mW)
1
10
1001
0.1
0.01
10 500
0.001
f = 10 kHz
f = 20 Hz
f = 1 kHz
THD+N (%)
OUTPUT POWER (mW)
1
10
100
1
0.1
0.01
10 500
0.001
f = 10 kHz
f = 20 Hz
f = 1 kHz
LM48820
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Typical Performance Characteristics (continued)
THD+N vs Output Power THD+N vs Output Power
VDD = 3V, RL= 16Ω, Stereo VDD = 3V, RL= 32Ω, Stereo
Figure 16. Figure 17.
Output Power vs Power Supply Voltage Output Power vs Power Supply Voltage
RL= 16Ω, f = 1kHz, Mono RL= 16Ω, f = 1kHz, Stereo
Figure 18. Figure 19.
Output Power vs Power Supply Voltage Output Power vs Power Supply Voltage
RL= 32Ω, f = 1kHz, Mono RL= 32Ω, f = 1kHz, Stereo
Figure 20. Figure 21.
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-50
-30
POWER SUPPLY REJECTION RATIO (dB)
FREQUENCY (Hz)
1k20
-10
-20
0
-40
-60
-70
-100
-90
-80
20k100
300
POWER DISSIPATION (mW)
OUTPUT POWER (mW)
020 100
200
150
0
50
100
6040 80
250
Mono
Stereo
300
POWER DISSIPATION (mW)
OUTPUT POWER (mW)
020 100
200
150
0
50
100
6040 80
250
Stereo
Mono
50
POWER DISSIPATION (mW)
OUTPUT POWER (mW)
100 2 12
40
30
0
10
20
64 8
Mono
Stereo
50
POWER DISSIPATION (mW)
OUTPUT POWER (mW) 100 2 12
40
30
0
10
20
64 8
Mono
Stereo
LM48820
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Typical Performance Characteristics (continued)
Power Dissipation vs Output Power Power Dissipation vs Output Power
VDD = 1.6V, RL= 16Ω, f = 1kHz VDD = 1.6V, RL= 32Ω, f = 1kHz
Figure 22. Figure 23.
Power Dissipation vs Output Power Power Dissipation vs Output Power
VDD = 3V, RL= 16Ω, f = 1kHz VDD = 3V, RL= 32Ω, f = 1kHz
Figure 24. Figure 25.
PSRR vs Frequency PSRR vs Frequency
VDD = 1.6V, RL= 16ΩVDD = 1.6V, RL= 32Ω
Figure 26. Figure 27.
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5
POWER SUPPLY CURRENT (mA)
POWER SUPPLY VOLTAGE (V)
30 4
6
4
3
5
0
1
2
1 2
5
POWER SUPPLY CURRENT (mA)
POWER SUPPLY VOLTAGE (V)
30 4
6
4
3
5
0
1
2
1 2
LM48820
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Typical Performance Characteristics (continued)
PSRR vs Frequency PSRR vs Frequency
VDD = 3V, RL= 16ΩVDD = 3V, RL= 32Ω
Figure 28. Figure 29.
Power Supply Current vs Power Supply Voltage Power Supply Current vs Power Supply Voltage
VIN = 0V, Mono VIN = 0V, Stereo
Figure 30. Figure 31.
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APPLICATION INFORMATION
SUPPLY VOLTAGE SEQUENCING
Before applying any signal to the inputs or shutdown pins of the LM48820, 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 LM48820 features a low noise inverting charge pump that generates an internal negative supply voltage.
This allows the outputs of the LM48820 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
LM48820 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 LM48820 when compared to a traditional headphone amplifier operating from the
same supply voltage.
OUTPUT TRANSIENT ('CLICK AND POPS') ELIMINATED
The LM48820 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 LM48820 has two internal operational amplifiers. The two amplifiers have internally
configured gain, the closed loop gain is set by selecting the ratio of Rfto Ri. Consequently, the gain for each
channel of the IC is
AV= -(Rf/ Ri) = 1.5 (V/V)
where
• RF= 30kΩ
• Ri= 20kΩ(1)
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/ (2π2RL) (W) (2)
Since the LM48820 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
LM48820 does not require heat sinking over a large range of ambient temperatures. From Equation 2 , assuming
a 3V power supply and a 16Ωload, the maximum power dissipation point is 28mW per amplifier. Thus the
maximum package dissipation point is 56mW. The maximum power dissipation point obtained must not be
greater than the power dissipation that results from Equation 3:
PDMAX = (TJMAX - TA) / (θJA) (W) (3)
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For this DSBGA package, θJA = 86°C/W and TJMAX = 150°C. 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 TAreduced. For the typical application of a 3V power supply, with a
16Ωload, the maximum ambient temperature possible without violating the maximum junction temperature is
approximately 127°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.
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 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 LM48820'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 LM48820’s shutdown function. When active, the LM48820’s micropower shutdown feature turns off
the amplifiers’ bias circuitry, reducing the supply current. The trigger point is 0.45V (max) for a logic-low level,
and 1.2V (min) for logic-high level. The low 0.05µA (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.
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 100kΩpull-up resistor
between the SD_LC/SD_RC pins and VDD. Connect the switch between the SD_LC/SD_RC pins and ground.
Select normal amplifier operation by opening the switch. Closing the switch connects the SD_LC/SD_RC pins to
ground, activating micro-power shutdown. The switch and resistor ensure that the SD_LC/SD_RC 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_LC/SD_RC pins. Driving the SD_LC/SD_RC pins with active
circuitry eliminates the pull-up resistor.
SELECTING PROPER EXTERNAL COMPONENTS
Optimizing the LM48820's performance requires properly selecting external components. Though the LM48820
operates well when using external components with wide tolerances, best performance is achieved by optimizing
component values.
Charge Pump Capacitor Selection
Use low (<100mΩ) ESR (equivalent series resistance) 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 (CC). A
larger valued CC(up to 3.3μF) improves load regulation and minimizes charge pump output resistance. The
switch-on resistance dominates the output impedance for capacitor values above 2.2μF.
The output ripple is affected by the value and ESR of the output capacitor (CSS). 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 LM48820 charge pump design is optimized for 2.2μF, low ESR, ceramic, flying, and output capacitors.
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Input Capacitor Value Selection
Amplifying the lowest audio frequencies requires high value input coupling capacitors (CINL and CINR 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, the input coupling capacitor has an effect on the LM48820'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, Riand the input capacitor, CINL and CINR, produce a -3dB high
pass filter cutoff frequency that is found using Equation 4.
f–3dB = 1 / 2πRiCIN (Hz) (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. REVISION HISTORY
Rev Date Description
1.0 05/09/07 Initial release.
1.1 05/15/07 Added the BOM table.
1.2 06/25/07 Deleted and replaced some curves. Input text edits also.
B 05/02/2013 Changed layout of National Data Sheet to TI format
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Product Folder Links: LM48820
PACKAGE OPTION ADDENDUM
www.ti.com 2-May-2013
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
(4)
Samples
LM48820TM/NOPB ACTIVE DSBGA YFR 14 250 Green (RoHS
& no Sb/Br) SNAGCU Level-1-260C-UNLIM -40 to 85 GI7
LM48820TMX/NOPB ACTIVE DSBGA YFR 14 3000 Green (RoHS
& no Sb/Br) SNAGCU Level-1-260C-UNLIM -40 to 85 GI7
(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) Multiple Top-Side Markings will be inside parentheses. Only one Top-Side 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 Top-Side 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.
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
LM48820TM/NOPB DSBGA YFR 14 250 178.0 8.4 1.7 1.7 0.76 4.0 8.0 Q1
LM48820TMX/NOPB DSBGA YFR 14 3000 178.0 8.4 1.7 1.7 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)
LM48820TM/NOPB DSBGA YFR 14 250 210.0 185.0 35.0
LM48820TMX/NOPB DSBGA YFR 14 3000 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 8-May-2013
Pack Materials-Page 2
YFR0014
www.ti.com
MECHANICAL DATA
4215090/A 12/12
TME14XXX (Rev A)
NOTES: A. All linear dimensions are in millimeters. Dimensioning and tolerancing per ASME Y14.5M-1994.
B. This drawing is subject to change without notice.
0.600
±0.075
D
E
D: Max =
E: Max =
1.64 mm, Min =
1.64 mm, Min =
1.58 mm
1.58 mm
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