LM4836
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LM4836 Stereo 2W Audio Power Amplifiers
with DC Volume Control, Bass Boost, and Input Mux
Check for Samples: LM4836
1FEATURES DESCRIPTION
The LM4836 is a monolithic integrated circuit that
2• PC98 and PC99 Compliant provides DC volume control, and stereo bridged
• DC Volume Control Interface audio power amplifiers capable of producing 2W into
• Input Mux 4Ωwith less than 1.0% THD+N, or 2.2W into 3Ωwith
less than 1.0% THD+N (see Notes below).
• System Beep Detect
• Stereo Switchable Bridged/Single-Ended Boomer audio integrated circuits were designed
specifically to provide high quality audio while
Power Amplifiers requiring a minimum amount of external components.
• Selectable Internal/External Gain and Bass The LM4836 incorporates a DC volume control,
Boost Configurable stereo bridged audio power amplifiers, selectable
• “Click and Pop” Suppression Circuitry gain or bass boost, and an input mux making it
optimally suited for multimedia monitors, portable
• Thermal Shutdown Protection Circuitry radios, desktop, and portable computer applications.
APPLICATIONS The LM4836 features an externally controlled, low-
power consumption shutdown mode, and both a
• Portable and Desktop Computers power amplifier and headphone mute for maximum
• Multimedia Monitors system flexibility and performance.
• Portable Radios, PDAs, and Portable TVs Note: When properly mounted to the circuit board,
the LM4836LQ and LM4836MTE will deliver 2W into
KEY SPECIFICATIONS 4Ω. The LM4836MT will deliver 1.1W into 8Ω. See
• POat 1% THD+N the APPLICATION INFORMATION section for
LM4836LQ and LM4836MTE usage information.
• Into 3Ω(LM4836LQ, LM4836MTE) 2.2 W (typ)
• Into 4Ω(LM4836LQ, LM4836MTE) 2.0 W (typ) Note: An LM4836LQ and LM4836MTE that have
been properly mounted to the circuit board and
• Into 8Ω(LM4836) 1.1 W (typ) forced-air cooled will deliver 2.2W into 3Ω.
• Single-Ended Mode - THD+N at 85 mW Into
32Ω1.0% (typ)
• Shutdown Current 0.2µA (typ)
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 © 1999–2013, 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.
LM4836
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Connection Diagram
Figure 1. WQFN Package
See Package NJB0028A
for Exposed-DAP WQFN
Figure 2. TSSOP Package
See Package PW0028A for TSSOP or
PWP0028A for Exposed-DAP HTSSOP
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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)
Supply Voltage 6.0V
Storage Temperature -65°C to +150°C
Input Voltage −0.3V to VDD +0.3V
Power Dissipation (3) Internally limited
ESD Susceptibility (4) 2500V
ESD Susceptibility (5) 250V
Junction Temperature 150°C
Soldering Information Vapor Phase (60 sec.) 215°C
Infrared (15 sec.) 220°C
See http://www.ti.com for other methods of soldering surface mount devices.
θJC (typ)—NJB0028A 3.0°C/W
θJA (typ)—NJB0028A (6) 42°C/W
θJC (typ)—PW0028A 20°C/W
θJA (typ)—PW0028A 80°C/W
θJC (typ)—PWP0028A 2°C/W
θJA (typ)—PWP0028A (7) 41°C/W
θJA (typ)—PWP0028A (8) 54°C/W
θJA (typ)—PWP0028A (9) 59°C/W
θJA (typ)—PWP0028A (10) 93°C/W
(1) If Military/Aerospace specified devices are required, please contact the Texas Instruments' Sales Office/ Distributors for availability and
specifications.
(2) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not ensured for parameters where no limit is given, however, the typical value is a good indication
of device performance.
(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. For the LM4836, TJMAX = 150°C. The typical junction-to-
ambient thermal resistance, when board mounted, is 80°C/W for the PW0028A package, 41°C/W for the PWP0028A package, and
42°C/W for the NJB0028A package.
(4) Human body model, 100 pF discharged through a 1.5 kΩresistor.
(5) Machine Model, 220 pF–240 pF discharged through all pins.
(6) The given θJA is for an LM4836 packaged in an NHW0024A with the exposed-DAP soldered to an exposed 2in2area of 1oz printed
circuit board copper.
(7) The θJA given is for a PWP0028A package whose exposed-DAP is soldered to a 2in2piece of 1 ounce printed circuit board copper on a
bottom side layer through 21 8mil vias.
(8) The θJA given is for a PWP0028A package whose exposed-DAP is soldered to an exposed 2in 2piece of 1 ounce printed circuit board
copper.
(9) The θJA given is for a PWP0028A package whose exposed-DAP is soldered to an exposed 1in 2piece of 1 ounce printed circuit board
copper.
(10) The θJA given is for a PWP0028A package whose exposed-DAP is not soldered to any copper.
OPERATING RATINGS
Temperature Range TMIN ≤TA≤TMAX −40°C ≤TA ≤85°C
Supply Voltage 2.7V≤VDD ≤5.5V
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ELECTRICAL CHARACTERISTICS FOR ENTIRE IC(1) (2)
The following specifications apply for VDD = 5V and TA= 25°C unless otherwise noted. LM4836 Units
Symbol Parameter Conditions (Limits)
Typical (3) Limit (4)
2.7 V (min)
VDD Supply Voltage 5.5 V (max)
IDD Quiescent Power Supply Current VIN = 0V, IO= 0A 15 30 mA (max)
ISD Shutdown Current Vpin 24 = VDD 0.2 2.0 μA (max)
VIH Headphone Sense High Input Voltage 4 V (min)
VIL Headphone Sense Low Input Voltage 0.8 V (max)
(1) All voltages are measured with respect to the ground pins, unless otherwise specified. All specifications are tested using the typical
application as shown in Figure 71.
(2) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not 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) Datasheet min/max specification limits are specified by design, test, or statistical analysis.
ELECTRICAL CHARACTERISTICS FOR VOLUME ATTENUATORS(1) (2)
The following specifications apply for VDD = 5V and TA= 25°C unless otherwise noted. LM4836 Units
Symbol Parameter Conditions (Limits)
Typical (3) Limit (4)
CRANGE Attenuator Range Gain with Vpin 5 ≥4.5V 0 ±0.5 dB (max)
0−1.0 dB (min)
CRANGE Attenuator Range Attenuation with Vpin 5 = 0V -73 -70 dB (min)
Vpin 3 = 5V, Bridged Mode -88 -80 dB (min)
AMMute Attenuation Vpin 3 = 5V, Single-Ended Mode -80 -70 dB (min)
(1) All voltages are measured with respect to the ground pins, unless otherwise specified. All specifications are tested using the typical
application as shown in Figure 71.
(2) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not 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) Datasheet min/max specification limits are specified by design, test, or statistical analysis.
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ELECTRICAL CHARACTERISTICS FOR SINGLE-ENDED MODE OPERATION(1) (2)
The following specifications apply for VDD = 5V and TA= 25°C unless otherwise noted. LM4836 Units
Symbol Parameter Conditions (Limits)
Typical (3) Limit (4)
THD+N = 1.0%; f = 1kHz; RL= 32Ω85 mW
POOutput Power THD+N = 10%; f = 1 kHz; RL= 32Ω95 mW
THD+N Total Harmonic Distortion+Noise VOUT = 1VRMS, f=1kHz, RL= 10kΩ, AVD 0.065 %
= 1
PSRR Power Supply Rejection Ratio CB= 1.0 μF, f =120 Hz, VRIPPLE = 200 58 dB
mVrms
SNR Signal to Noise Ratio POUT =75 mW, R L= 32Ω, A-Wtd Filter 102 dB
Xtalk Channel Separation f=1kHz, CB= 1.0 μF 65 dB
(1) All voltages are measured with respect to the ground pins, unless otherwise specified. All specifications are tested using the typical
application as shown in Figure 71.
(2) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not 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) Datasheet min/max specification limits are specified by design, test, or statistical analysis.
ELECTRICAL CHARACTERISTICS FOR BRIDGED MODE OPERATION(1) (2)
The following specifications apply for VDD = 5V and TA= 25°C unless otherwise noted. LM4836 Units
Symbol Parameter Conditions (Limits)
Typical (3) Limit (4)
VOS Output Offset Voltage VIN = 0V 10 50 mV (max)
THD + N = 1.0%; f=1kHz; RL= 3Ω(5) (6) 2.2 W
THD + N = 1.0%; f=1kHz; RL= 4Ω(7) (6) 2 W
POOutput Power THD = 1.5% (max);f = 1 kHz; RL= 8Ω1.1 1.0 W (min)
THD+N = 10%;f = 1 kHz; RL= 8Ω1.5 W
THD+N Total Harmonic Distortion+Noise PO= 1W, 20 Hz< f < 20 kHz, 0.3 %
RL= 8Ω, AVD = 2
PO= 340 mW, RL= 32Ω1.0 %
CB= 1.0 µF, f = 120 Hz, 74 dB
PSRR Power Supply Rejection Ratio VRIPPLE = 200 mVrms; RL= 8Ω
SNR Signal to Noise Ratio VDD = 5V, POUT = 1.1W, RL= 8Ω, A-Wtd 93 dB
Filter
Xtalk Channel Separation f=1kHz, CB= 1.0 μF 70 dB
(1) All voltages are measured with respect to the ground pins, unless otherwise specified. All specifications are tested using the typical
application as shown in Figure 71.
(2) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. Electrical Characteristics state DC and AC electrical
specifications under particular test conditions which ensure specific performance limits. This assumes that the device is within the
Operating Ratings. Specifications are not 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) Datasheet min/max specification limits are specified by design, test, or statistical analysis.
(5) When driving 3Ωloads and operating on a 5V supply the LM4836MTE exposed DAP must be soldered to the circuit board and forced-
air cooled.
(6) When driving 3Ωor 4Ωloads and operating on a 5V supply, the LM4836LQ must be mounted to the circuit board that has a minimum of
2.5in2of exposed, uninterrupted copper area connected to the WQFN package's exposed DAP.
(7) When driving 4Ωloads and operating on a 5V supply the LM4836MTE exposed DAP must be soldered to the circuit board.
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TYPICAL APPLICATION
Figure 3. Typical Application Circuit
TRUTH TABLE FOR LOGIC INPUTS (1)
Mute Mux Control HP Sense Inputs Selected Bridged Output Single-Ended
Output
0 0 0 Left In 1, Right In 1 Vol. Adjustable -
0 0 1 Left In 1, Right In 1 Muted Vol. Adjustable
0 1 0 Left In 2, Right In 2 Vol. Adjustable -
0 1 1 Left In 2, Right In 2 Muted Vol. Adjustable
1 X X - Muted Muted
(1) If system beep is detected on the Beep in pin (pin 11) and beep is fed to inputs, the system beep will be passed through the bridged
amplifier regardless of the logic of the Mute, HP sense, or DC Volume Control pins.
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TYPICAL PERFORMANCE CHARACTERISTICS MTE SPECIFIC CHARACTERISTICS
LM4836MTE THD+N vs Output Power LM4836MTE THD+N vs Frequency
Figure 4. Figure 5.
LM4836MTE THD+N vs Output Power LM4836MTE THD+N vs Frequency
Figure 6. Figure 7.
LM4836MTE Power Dissipation vs Output Power LM4836LQ Power Derating Curve
Figure 8. Figure 9.
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TYPICAL PERFORMANCE CHARACTERISTICS MTE SPECIFIC CHARACTERISTICS (continued)
LM4836MTE Power Derating Curve
Figure 10 shows the thermal dissipation ability of the LM4836MTE at different ambient temperatures given these conditions:
500LFPM + 2in2: The part is soldered to a 2in2, 1 oz. copper plane with 500 linear feet per minute of forced-air flow across it. 2in2on
bottom: The part is soldered to a 2in2, 1oz. copper plane that is on the bottom side of the PC board through 21 8 mil vias. 2in2: The
part is soldered to a 2in2, 1oz. copper plane. 1in2: The part is soldered to a 1in2, 1oz. copper plane. Not Attached: The part is not
soldered down and is not forced-air cooled. Figure 10.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC CHARACTERISTICS
THD+N Vs Frequency THD+N Vs Frequency
Figure 11. Figure 12.
THD+N Vs Frequency THD+N Vs Frequency
Figure 13. Figure 14.
THD+N Vs Frequency THD+N Vs Frequency
Figure 15. Figure 16.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
THD+N Vs Frequency THD+N Vs Frequency
Figure 17. Figure 18.
THD+N Vs Frequency THD+N Vs Frequency
Figure 19. Figure 20.
THD+N Vs Frequency THD+N Vs Output Power
Figure 21. Figure 22.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
THD+N Vs Output Power THD+N Vs Output Power
Figure 23. Figure 24.
THD+N Vs Output Power THD+N Vs Output Power
Figure 25. Figure 26.
THD+N vs Output Power THD+N Vs Output Power
Figure 27. Figure 28.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
THD+N Vs Output Power THD+N Vs Output Power
Figure 29. Figure 30.
THD+N Vs Output Power THD+N Vs Output Power
Figure 31. Figure 32.
THD+N Vs Output Voltage Docking Station Pins THD+N Vs Output Voltage Docking Station Pins
Figure 33. Figure 34.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
Output Power Vs Load Resistance Output Power Vs Load Resistance
Figure 35. Figure 36.
Output Power Vs Load Resistance Power Supply Rejection Ratio
Figure 37. Figure 38.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
Dropout Voltage Output Power Vs Load Resistance
Figure 39. Figure 40.
Noise Floor Noise Floor
Figure 41. Figure 42.
Volume Control Characteristics Power Dissipation Vs Output Power
Figure 43. Figure 44.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
Power Dissipation Vs Output Power External Gain/ Bass Boost Characteristics
Figure 45. Figure 46.
Power Derating Curve Crosstalk
Figure 47. Figure 48.
Crosstalk Output Power Vs Supply Voltage
Figure 49. Figure 50.
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TYPICAL PERFORMANCE CHARACTERISTICS NON-MTE SPECIFIC
CHARACTERISTICS (continued)
Output Power Vs Supply Voltage Supply Current Vs Supply Voltage
Figure 51. Figure 52.
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TYPICAL PERFORMANCE CHARACTERISTICS
Output Power vs Load Resistance Output Power vs Load Resistance
Figure 53. Figure 54.
Output Power vs Load Resistance Power Supply Rejection Ratio
Figure 55. Figure 56.
Dropout Voltage Output Power vs Load Resistance
Figure 57. Figure 58.
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Noise Floor Noise Floor
Figure 59. Figure 60.
Volume Control Characteristics Power Dissipation vs Output Power
Figure 61. Figure 62.
Power Dissipation vs Output Power External Gain/ Bass Boost Characteristics
Figure 63. Figure 64.
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Power Derating Curve Crosstalk
Figure 65. Figure 66.
Crosstalk Output Power vs Supply voltage
Figure 67. Figure 68.
Output Power vs Supply Voltage Supply Current vs Supply Voltage
Figure 69. Figure 70.
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APPLICATION INFORMATION
EXPOSED-DAP PACKAGE PCB MOUNTING CONSIDERATIONS
The LM4836's exposed-DAP (die attach paddle) packages (MTE and LQ) provide a low thermal resistance
between the die and the PCB to which the part is mounted and soldered. This allows rapid heat transfer from the
die to the surrounding PCB copper traces, ground plane and, finally, surrounding air. The result is a low voltage
audio power amplifier that produces 2.1W at ≤1% THD with a 4Ωload. This high power is achieved through
careful consideration of necessary thermal design. Failing to optimize thermal design may compromise the
LM4836's high power performance and activate unwanted, though necessary, thermal shutdown protection.
The MTE and LQ packages must have their DAPs soldered to a copper pad on the PCB. The DAP's PCB copper
pad is connected to a large plane of continuous unbroken copper. This plane forms a thermal mass and heat
sink and radiation area. Place the heat sink area on either outside plane in the case of a two-sided PCB, or on
an inner layer of a board with more than two layers. Connect the DAP copper pad to the inner layer or backside
copper heat sink area with 32(4x8) (MTE) or 6(3x2) (LQ) vias. The via diameter should be 0.012in–0.013in with a
1.27mm pitch. Ensure efficient thermal conductivity by plating-through and solder-filling the vias.
Best thermal performance is achieved with the largest practical copper heat sink area. If the heatsink and
amplifier share the same PCB layer, a nominal 2.5in2(min) area is necessary for 5V operation with a 4Ωload.
Heatsink areas not placed on the same PCB layer as the LM4836 should be 5in2(min) for the same supply
voltage and load resistance. The last two area recommendations apply for 25°C ambient temperature. Increase
the area to compensate for ambient temperatures above 25°C. In systems using cooling fans, the LM4836MTE
can take advantage of forced air cooling. With an air flow rate of 450 linear-feet per minute and a 2.5in2exposed
copper or 5.0in2inner layer copper plane heatsink, the LM4836MTE can continuously drive a 3Ωload to full
power. The LM4836LQ achieves the same output power level without forced air cooling. In all circumstances and
conditions, the junction temperature must be held below 150°C to prevent activating the LM4836's thermal
shutdown protection. The LM4836's power de-rating curve in the TYPICAL PERFORMANCE
CHARACTERISTICS MTE SPECIFIC CHARACTERISTICS shows the maximum power dissipation versus
temperature. Example PCB layouts for the exposed-DAP TSSOP and LQ packages are shown in the
RECOMMENDED PRINTED CIRCUIT BOARD LAYOUT section. Further detailed and specific information
concerning PCB layout, fabrication, and mounting an LQ (WQFN) package is available in Texas Instruments' AN-
1187 (literature number SNOA401).
PCB LAYOUT AND SUPPLY REGULATION CONSIDERATIONS FOR DRIVING 3ΩAND 4Ω
LOADS
Power dissipated by a load is a function of the voltage swing across the load and the load's impedance. As load
impedance decreases, load dissipation becomes increasingly dependent on the interconnect (PCB trace and
wire) resistance between the amplifier output pins and the load's connections. Residual trace resistance causes
a voltage drop, which results in power dissipated in the trace and not in the load as desired. For example, 0.1Ω
trace resistance reduces the output power dissipated by a 4Ωload from 2.1W to 2.0W. This problem of
decreased load dissipation is exacerbated as load impedance decreases. Therefore, to maintain the highest load
dissipation and widest output voltage swing, PCB traces that connect the output pins to a load must be as wide
as possible.
Poor power supply regulation adversely affects maximum output power. A poorly regulated supply's output
voltage decreases with increasing load current. Reduced supply voltage causes decreased headroom, output
signal clipping, and reduced output power. Even with tightly regulated supplies, trace resistance creates the
same effects as poor supply regulation. Therefore, making the power supply traces as wide as possible helps
maintain full output voltage swing.
BRIDGE CONFIGURATION EXPLANATION
As shown in Figure 3, the LM4836 consists of two pairs of operational amplifiers, forming a two-channel (channel
A and channel B) stereo amplifier. (Though the following discusses channel A, it applies equally to channel B.)
External resistors Rfand Riset the closed-loop gain of Amp1A, whereas two internal 20kΩresistors set Amp2A's
gain at −1. The LM4836 drives a load, such as a speaker, connected between the two amplifier outputs, −OUTA
and +OUTA.
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Figure 3 shows that Amp1A's output serves as Amp2A's input. This results in both amplifiers producing signals
identical in magnitude, but 180° out of phase. Taking advantage of this phase difference, a load is placed
between −OUTA and +OUTA and driven differentially (commonly referred to as “bridge mode”). This results in a
differential gain of
AVD = 2 * (Rf/R i) (1)
Bridge mode amplifiers are different from single-ended amplifiers that drive loads connected between a single
amplifier's output and ground. For a given supply voltage, bridge mode has a distinct advantage over the single-
ended configuration: its differential output doubles the voltage swing across the load. This produces four times
the output power when 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 that the output signal is not clipped.
To ensure minimum output signal clipping when choosing an amplifier's closed-loop gain, refer to the AUDIO
POWER AMPLIFIER DESIGN section.
Another advantage of the differential bridge output is no net DC voltage across the load. This is accomplished by
biasing channel A's and channel B's outputs at half-supply. This eliminates the coupling capacitor that single
supply, single-ended amplifiers require. Eliminating an output coupling capacitor in a single-ended configuration
forces a single-supply amplifier's half-supply bias voltage across the load. This increases internal IC power
dissipation and may permanently damage loads such as speakers.
POWER DISSIPATION
Power dissipation is a major concern when designing a successful single-ended or bridged amplifier. 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)Single-Ended (2)
However, a direct consequence of the increased power delivered to the load by a bridge amplifier is higher
internal power dissipation for the same conditions.
The LM4836 has two operational amplifiers per channel. The maximum internal power dissipation per channel
operating in the bridge mode is four times that of a single-ended amplifier. From Equation 3, assuming a 5V
power supply and a 4Ωload, the maximum single channel power dissipation is 1.27W or 2.54W for stereo
operation.
PDMAX = 4 * (VDD)2/(2π2RL)Bridge Mode (3)
The LM4836's power dissipation is twice that given by Equation 2 or Equation 3 when operating in the single-
ended mode or bridge mode, respectively. Twice the maximum power dissipation point given by Equation 3 must
not exceed the power dissipation given by Equation 4:
PDMAX′= (TJMAX −TA)/θJA (4)
The LM4836's TJMAX = 150°C. In the LQ package soldered to a DAP pad that expands to a copper area of 5in2
on a PCB, the LM4836's θJA is 20°C/W. In the MTE package soldered to a DAP pad that expands to a copper
area of 2in2on a PCB, the LM4836's θJA is 41°C/W. At any given ambient temperature TA, use Equation 4 to find
the maximum internal power dissipation supported by the IC packaging. Rearranging Equation 4and substituting
PDMAX for PDMAX′results in Equation 5. This equation gives the maximum ambient temperature that still allows
maximum stereo power dissipation without violating the LM4836's maximum junction temperature.
TA= TJMAX – 2*PDMAX θJA (5)
For a typical application with a 5V power supply and an 4Ωload, the maximum ambient temperature that allows
maximum stereo power dissipation without exceeding the maximum junction temperature is approximately 99°C
for the LQ package and 45°C for the MTE package.
TJMAX = PDMAX θJA + TA(6)
Equation 6 gives the maximum junction temperature TJMAX. If the result violates the LM4836's 150°C, reduce the
maximum junction temperature by reducing the power supply voltage or increasing the load resistance. Further
allowance should be made for increased ambient temperatures.
The above examples assume that a device is a surface mount part operating around the maximum power
dissipation point. Since internal power dissipation is a function of output power, higher ambient temperatures are
allowed as output power or duty cycle decreases.
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If the result of Equation 2 is greater than that of Equation 3, then decrease the supply voltage, increase the load
impedance, or reduce the ambient temperature. If these measures are insufficient, a heat sink can be added to
reduce θJA. The heat sink can be created using additional copper area around the package, with connections to
the ground pin(s), supply pin and amplifier output pins. External, solder attached SMT heatsinks such as the
Thermalloy 7106D can also improve power dissipation. When adding a heat sink, the θJA is the sum of θJC,θCS,
and θSA. (θJC is the junction-to-case thermal impedance, θCS is the case-to-sink thermal impedance, and θSA is
the sink-to-ambient thermal impedance.) Refer to the TYPICAL PERFORMANCE CHARACTERISTICS MTE
SPECIFIC CHARACTERISTICS curves for power dissipation information at lower output power levels.
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 5V regulator typically use a 10 µF in parallel with a 0.1 µF filter capacitors to
stabilize the regulator's output, reduce noise on the supply line, and improve the supply's transient response.
However, their presence does not eliminate the need for a local 1.0 µF tantalum bypass capacitance connected
between the LM4836's supply pins and ground. Do not substitute a ceramic capacitor for the tantalum. Doing so
may cause oscillation. Keep the length of leads and traces that connect capacitors between the LM4836's power
supply pin and ground as short as possible. Connecting a 1µF capacitor, CB, between the BYPASS pin and
ground improves the internal bias voltage's stability and improves the amplifier's PSRR. The PSRR
improvements increase as the bypass pin capacitor value increases. Too large, however, increases turn-on time
and can compromise amplifier's click and pop performance. The selection of bypass capacitor values, especially
CB, depends on desired PSRR requirements, click and pop performance (as explained in the section, PROPER
SELECTION OF EXTERNAL COMPONENTS ), system cost, and size constraints.
PROPER SELECTION OF EXTERNAL COMPONENTS
Optimizing the LM4836's performance requires properly selecting external components. Though the LM4836
operates well when using external components with wide tolerances, best performance is achieved by optimizing
component values.
The LM4836 is unity-gain stable, giving a designer maximum design flexibility. The gain should be set to no more
than a given application requires. This allows the amplifier to achieve minimum THD+N and maximum signal-to-
noise ratio. These parameters are compromised as the closed-loop gain increases. However, low gain demands
input signals with greater voltage swings to achieve maximum output power. Fortunately, many signal sources
such as audio CODECs have outputs of 1VRMS (2.83VP-P). Please refer to the AUDIO POWER AMPLIFIER
DESIGN section for more information on selecting the proper gain.
Input Capacitor Value Selection
Amplifying the lowest audio frequencies requires high value input coupling capacitor (0.33µF in Figure 3). 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 large input capacitor.
Besides effecting system cost and size, the input coupling capacitor has an affect on the LM4835's click and pop
performance. When the supply voltage is first applied, a transient (pop) is created as the charge on the input
capacitor changes from zero to a quiescent state. The magnitude of the pop is directly proportional to the input
capacitor's size. Higher value capacitors need more time to reach a quiescent DC voltage (usually VDD/2) when
charged with a fixed current. The amplifier's output charges the input capacitor through the feedback resistor, Rf.
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 3, the input resistor (20kΩ) and the input capacitor produce a −3dB high pass filter cutoff
frequency that is found using Equation 7.
(7)
As an example when using a speaker with a low frequency limit of 150Hz, the input coupling capacitor using
Equation 7, is 0.063µF. The 0.33µF input coupling capacitor shown in Figure 3 allows the LM4835 to drive high
efficiency, full range speaker whose response extends below 30Hz.
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OPTIMIZING CLICK AND POP REDUCTION PERFORMANCE
The LM4836 contains circuitry that minimizes turn-on and shutdown transients or “clicks and pop”. For this
discussion, turn-on refers to either applying the power supply voltage or when the shutdown mode is deactivated.
While the power supply is ramping to its final value, the LM4836's internal amplifiers are configured as unity gain
buffers. An internal current source changes the voltage of the BYPASS pin in a controlled, linear manner. Ideally,
the input and outputs track the voltage applied to the BYPASS pin. The gain of the internal amplifiers remains
unity until the voltage on the bypass pin reaches 1/2 VDD. As soon as the voltage on the bypass pin is stable, the
device becomes fully operational. Although the BYPASS pin current cannot be modified, changing the size of CB
alters the device's turn-on time and the magnitude of “clicks and pops”. Increasing the value of CBreduces the
magnitude of turn-on pops. However, this presents a tradeoff: as the size of CBincreases, the turn-on time
increases. There is a linear relationship between the size of CBand the turn-on time. Here are some typical turn-
on times for various values of CB:
CBTON
0.01µF 2ms
0.1µF 20ms
0.22µF 44ms
0.47µF 94ms
1.0µF 200ms
In order eliminate “clicks and pops”, all capacitors must be discharged before turn-on. Rapidly switching VDD may
not allow the capacitors to fully discharge, which may cause “clicks and pops”. In a single-ended configuration,
the output is coupled to the load by COUT. This capacitor usually has a high value. COUT discharges through
internal 20kΩresistors. Depending on the size of COUT, the discharge time constant can be relatively large. To
reduce transients in single-ended mode, an external 1kΩ–5kΩresistor can be placed in parallel with the internal
20kΩresistor. The tradeoff for using this resistor is increased quiescent current.
Figure 71. Resistor for Varying Output Loads
DOCKING STATION
Applications such as notebook computers can take advantage of a docking station to connect to external devices
such as monitors or audio/visual equipment that sends or receives line level signals. The LM4836 has two
outputs, Pin 9 and Pin 13, which connect to outputs of the internal input amplifiers that drive the volume control
inputs. These input amplifiers can drive loads of >1kΩ(such as powered speakers) with a rail-to-rail signal. Since
the output signal present on the RIGHT DOCK and LEFT DOCK pins is biased to VDD/2, coupling capacitors
should be connected in series with the load. Typical values for the coupling capacitors are 0.33µF to 1.0µF. If
polarized coupling capacitors are used, connect their "+" terminals to the respective output pin.
Since the DOCK outputs precede the internal volume control, the signal amplitude will be equal to the input
signal's magnitude and cannot be adjusted. However, the input amplifier's closed-loop gain can be adjusted
using external resistors. These resistors are shown in Figure 71 as 20kΩdevices that set each input amplifier's
gain to -1. Use Equation 8 to determine the input and feedback resistor values for a desired gain.
- Av= RF/ Ri(8)
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Adjusting the input amplifier's gain sets the minimum gain for that channel. The DOCK outputs adds circuit and
functional flexibility because their use supercedes using the inverting outputs of each bridged output amplifier as
line-level outputs.
STEREO-INPUT MULTIPLEXER (STEREO MUX)
The LM4836 has two stereo inputs. The MUX CONTROL pin controls which stereo input is active. Applying 0V to
the MUX CONTROL pin selects stereo input 1. Applying VDD to the MUX CONTROL pin selects stereo input 2.
BEEP DETECT FUNCTION
Computers and notebooks produce a system "beep" signal that drives a small speaker. The speaker's auditory
output signifies that the system requires user attention or input. To accommodate this system alert signal, the
LM4836's pin 11 is a mono input that accepts the beep signal. Internal level detection circuitry at this input
monitors the beep signal's magnitude. When a signal level greater than VDD/2 is detected on pin 11, the bridge
output amplifiers are enabled. The beep signal is amplified and applied to the load connected to the output
amplifiers. A valid beep signal will be applied to the load even when MUTE is active. Use the input resistors
connected between the BEEP IN pin and the stereo input pins to accommodate different beep signal amplitudes.
These resistors are shown as 200kΩdevices in Figure 71. Use higher value resistors to reduce the gain applied
to the beep signal. The resistors must be used to pass the beep signal to the stereo inputs. The BEEP IN pin is
used only to detect the beep signal's magnitude: it does not pass the signal to the output amplifiers. The
LM4836's shutdown mode must be deactivated before a system alert signal is applied to BEEP IN pin.
MICRO-POWER SHUTDOWN
The voltage applied to the SHUTDOWN pin controls the LM4836's shutdown function. Activate micro-power
shutdown by applying VDD to the SHUTDOWN pin. When active, the LM4836's micro-power shutdown feature
turns off the amplifier's bias circuitry, reducing the supply current. The logic threshold is typically VDD/2. The low
0.7 µA typical shutdown current is achieved by applying a voltage that is as near as VDD as possible to the
SHUTDOWN pin. A voltage that is less than VDD may increase the shutdown current. Logic Level Truth Table
shows the logic signal levels that activate and deactivate micro-power shutdown and headphone amplifier
operation.
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 10kΩpull-up resistor
between the SHUTDOWN pin and VDD. Connect the switch between the SHUTDOWN pin and ground. Select
normal amplifier operation by closing the switch. Opening the switch connects the SHUTDOWN pin to VDD
through the pull-up resistor, activating micro-power shutdown. The switch and resistor specify that the
SHUTDOWN pin will not float. This prevents unwanted state changes. In a system with a microprocessor or a
microcontroller, use a digital output to apply the control voltage to the SHUTDOWN pin. Driving the SHUTDOWN
pin with active circuitry eliminates the pull up resistor.
Table 1. Logic Level Truth Table for SHUTDOWN, HP-IN, and MUX Operation
SHUTDOWN HP-IN PIN MUX CHANNEL OPERATIONAL MODE
PIN SELECT PIN (MUX INPUT CHANNEL #)
Logic Low Logic Low Logic Low Bridged Amplifiers (1)
Logic Low Logic Low Logic High Bridged Amplifiers (2)
Logic Low Logic High Logic Low Single-Ended Amplifiers (1)
Logic Low Logic High Logic High Single-Ended Amplifiers (2)
Logic High X X Micro-Power Shutdown
MUTE FUNCTION
The LM4836 mutes the amplifier and DOCK outputs when VDD is applied to pin 5, the MUTE pin. Even while
muted, the LM4836 will amplify a system alert (beep) signal whose magnitude satisfies the BEEP DETECT
circuitry. Applying 0V to the MUTE pin returns the LM4836 to normal, unmated operation. Prevent unanticipated
mute behavior by connecting the MUTE pin to VDD or ground. Do not let pin 5 float.
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HP SENSE FUNCTION
Applying a voltage between 4V and VDD to the LM4836's HP-IN headphone control pin turns off Amp2A and
Amp2B, muting a bridged-connected load. Quiescent current consumption is reduced when the IC is in this
single-ended mode.
Figure 72 shows the implementation of the LM4836's headphone control function. With no headphones
connected to the headphone jack, the R1-R2 voltage divider sets the voltage applied to the HP-IN pin (pin 16) at
approximately 50mV. This 50mV enables Amp1B and Amp2B, placing the LM4836 in bridged mode operation.
The output coupling capacitor blocks the amplifier's half supply DC voltage, protecting the headphones.
The HP-IN threshold is set at 4V. While the LM4836 operates in bridged mode, the DC potential across the load
is essentially 0V. Therefore, even in an ideal situation, the output swing cannot cause a false single-ended
trigger. Connecting headphones to the headphone jack disconnects the headphone jack contact pin from −OUTA
and allows R1 to pull the HP Sense pin up to VDD. This enables the headphone function, turns off Amp2A and
Amp2B, and mutes the bridged speaker. The amplifier then drives the headphones, whose impedance is in
parallel with resistor R2 and R3. These resistors have negligible effect on the LM4836's output drive capability
since the typical impedance of headphones is 32Ω.
Figure 72 also shows the suggested headphone jack electrical connections. The jack is designed to mate with a
three-wire plug. The plug's tip and ring should each carry one of the two stereo output signals, whereas the
sleeve should carry the ground return. A headphone jack with one control pin contact is sufficient to drive the HP-
IN pin when connecting headphones.
A microprocessor or a switch can replace the headphone jack contact pin. When a microprocessor or switch
applies a voltage greater than 4V to the HP-IN pin, a bridge-connected speaker is muted and Amp1A and
Amp2A drive a pair of headphones.
Figure 72. Headphone Sensing Circuit
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BASS BOOST FUNCTION
The LM4836 has a bass-boost feature that enhances the low frequency response in applications using small
speakers. The voltage level applied to the BASS BOOST SELECT pin controls the bass-boost function. Applying
GND activates the bass-boost mode. In bass-boost mode, the LM4836's gain is increased at low frequencies,
with a corner frequency set by the external capacitor, CBASS. Applying VDD defeats the bass-boost mode and
selects unity gain. Tying the BASS BOOST SELECT pin to VDD permanently defeats the bass-boost function.
Enabling bass-boost forces the output amplifiers to operate with an internally set low frequency gain of 2 (gain of
4 in bridged mode). The capacitor CBASS shown in Figure 3 sets the bass-boost corner frequency. At low
frequencies, the capacitor is a virtual open circuit and the feedback resistance consists of two 10kΩresistors. At
high frequencies, the capacitor is a virtual short circuit, which shorts one of the two 10kΩfeedback resistors. The
results is bridge amplifier gain that increases at low frequencies. A first-order pole is formed with a corner
frequency at
fC= 1/(2π10kΩCBASS) (9)
At f<<fC, the differential gain of this bridged amplifier is
2(10kΩ+ 10kΩ) /10kΩ= 4 (10)
With CBASS = 0.1µF, the first-order pole has a corner frequency of 160Hz. It is assumed when using Equation 9
that CO, Ci, fIC, and fOC, are chosen for the desired low frequency response as explained in the PROPER
SELECTION OF EXTERNAL COMPONENTS section. See the TYPICAL PERFORMANCE CHARACTERISTICS
MTE SPECIFIC CHARACTERISTICS section for a graph that includes bass-boost performance with various
values of CBASS.
DC VOLUME CONTROL
The LM4836 has an internal stereo volume control whose setting is a function of the DC voltage applied to the
DC VOL CONTROL pin. The volume control's voltage input range is 0V to VDD. The volume range is from 0dB
(DC control voltage = 80%VDD) to -80dB (DC control voltage = 0V). The volume remains at 0dB for DC control
voltages greater than 80%VDD. When the MODE input is 0V, the LM4836 operates at unity gain, bypassing the
volume control. A graph showing a typical volume response versus DC control voltage is shown in the TYPICAL
PERFORMANCE CHARACTERISTICS MTE SPECIFIC CHARACTERISTICS section.
Like all volume controls, the LM4836's internal volume control is set while listening to an amplified signal that is
applied to an external speaker. The actual voltage applied to the DC VOL CONTROL pin is a result of the
volume a listener desires. As such, the volume control is designed for use in a feedback system that includes
human ears and preferences. This feedback system operates quite well without the need for accurate gain. The
user simply sets the volume to the desired level as determined by their ear, without regard to the actual DC
voltage that produces the volume. Therefore, the accuracy of the volume control is not critical, as long as the
volume changes monotonically, matches well between stereo channels, and the step size is small enough to
reach a desired volume that is not too loud or too soft. Since gain accuracy is not critical, there will be volume
variation from part-to-part even with the same applied DC control voltage. The gain of a given LM4836 can be
set with a fixed external voltage, but another LM4836 may require a different control voltage to achieve the same
gain. The typical part-to-part variation can be as large as 8dB for the same control voltage.
AUDIO POWER AMPLIFIER DESIGN
Audio Amplifier Design: Driving 1W into an 8ΩLoad
The following are the desired operational parameters:
Power Output: 1 WRMS
Load Impedance: 8Ω
Input Level: 1 VRMS
Input Impedance: 20 kΩ
Bandwidth: 100 Hz−20 kHz ± 0.25 dB
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The design begins by specifying the minimum supply voltage necessary to obtain the specified output power.
One way to find the minimum supply voltage is to use the Output Power vs Supply Voltage curve in the TYPICAL
PERFORMANCE CHARACTERISTICS section. Another way, using Equation 11, is to calculate the peak output
voltage necessary to achieve the desired output power for a given load impedance. To account for the amplifier's
dropout voltage, two additional voltages, based on the Dropout Voltage vs Supply Voltage in the TYPICAL
PERFORMANCE CHARACTERISTICS curves, must be added to the result obtained by Equation 11. The result
is Equation 12.
(11)
VDD ≥(VOUTPEAK+ (VODTOP + VODBOT)) (12)
The Output Power vs Supply Voltage graph for an 8Ωload indicates a minimum supply voltage of 4.6V. This is
easily met by the commonly used 5V supply voltage. The additional voltage creates the benefit of headroom,
allowing the LM4836 to produce peak output power in excess of 1W without clipping or other audible distortion.
The choice of supply voltage must also not create a situation that violates of maximum power dissipation as
explained above in the POWER DISSIPATION section.
After satisfying the LM4836's power dissipation requirements, the minimum differential gain needed to achieve
1W dissipation in an 8Ωload is found using Equation 13.
(13)
Thus, a minimum gain of 2.83 allows the LM4836's to reach full output swing and maintain low noise and THD+N
performance. For this example, let AVD = 3.
The amplifier's overall gain is set using the input (Ri) and feedback (Ri) resistors. With the desired input
impedance set at 20kΩ, the feedback resistor is found using Equation 14.
Rf/Ri= AVD/2 (14)
The value of Rfis 30kΩ.
The last step in this design example is setting the amplifier's −3dB frequency bandwidth. To achieve the desired
±0.25dB pass band magnitude variation limit, the low frequency response must extend to at least one-fifth the
lower bandwidth limit and the high frequency response must extend to at least five times the upper bandwidth
limit. The gain variation for both response limits is 0.17dB, well within the ±0.25dB desired limit. The results are
an fL= 100Hz/5 = 20Hz (15)
and an
fH= 20kHz x 5 = 100kHz (16)
As mentioned in the PROPER SELECTION OF EXTERNAL COMPONENTS section, Riand Cicreate a
highpass filter that sets the amplifier's lower bandpass frequency limit. Find the coupling capacitor's value using
Equation 17.
Ci≥1/(2πRifL) (17)
The result is
1/(2π*20kΩ*20Hz) = 0.397μF (18)
Use a 0.39μF capacitor, the closest standard value.
The product of the desired high frequency cutoff (100kHz in this example) and the differential gain AVD,
determines the upper passband response limit. With AVD = 3 and fH= 100kHz, the closed-loop gain bandwidth
product (GBWP) is 300kHz. This is less than the LM4836's 3.5MHz GBWP. With this margin, the amplifier can
be used in designs that require more differential gain while avoiding performance,restricting bandwidth
limitations.
RECOMMENDED PRINTED CIRCUIT BOARD LAYOUT
Figure 73 through Figure 77 show the recommended four-layer PC board layout that is optimized for the 8-pin
LQ-packaged LM4836 and associated external components. This circuit is designed for use with an external 5V
supply and 4Ωspeakers.
This circuit board is easy to use. Apply 5V and ground to the board's VDD and GND pads, respectively. Connect
4Ωspeakers between the board's −OUTA and +OUTA and OUTB and +OUTB pads.
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REVISION HISTORY
Changes from Revision E (May 2013) to Revision F Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 30
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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
LM4836LQ/NOPB ACTIVE WQFN NJB 28 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 L4836LQ
LM4836MTEX/NOPB ACTIVE HTSSOP PWP 28 2500 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 85 LM4836MTE
(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
LM4836LQ/NOPB WQFN NJB 28 1000 178.0 12.4 5.3 5.3 1.3 8.0 12.0 Q1
LM4836MTEX/NOPB HTSSOP PWP 28 2500 330.0 16.4 6.8 10.2 1.6 8.0 16.0 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)
LM4836LQ/NOPB WQFN NJB 28 1000 210.0 185.0 35.0
LM4836MTEX/NOPB HTSSOP PWP 28 2500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 8-May-2013
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
TYP
6.6
6.2
1.1 MAX
26X 0.65
28X 0.30
0.19
2X
8.45
TYP
0.20
0.09
0 - 8
0.10
0.02
5.65
5.25
3.15
2.75
(1)
0.25
GAGE PLANE
0.7
0.5
A
NOTE 3
9.8
9.6
B
NOTE 4
4.5
4.3
4214870/A 10/2014
PowerPAD - 1.1 mm max heightPWP0028A
PLASTIC SMALL OUTLINE
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm, per side.
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm, per side.
5. Reference JEDEC registration MO-153, variation AET.
PowerPAD is a trademark of Texas Instruments.
TM
128
0.1 C A B
15
14
PIN 1 ID
AREA
SEATING PLANE
0.1 C
SEE DETAIL A
DETAIL A
TYPICAL
SCALE 1.800
THERMAL
PAD
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EXAMPLE BOARD LAYOUT
0.05 MAX
ALL AROUND
0.05 MIN
ALL AROUND
28X (1.3)
(6.1)
28X (0.45)
(0.9) TYP
28X (1.5)
28X (0.45)
26X
(0.65)
(3)
(3.4)
NOTE 9
(5.5)
SOLDER
MASK
OPENING
(9.7)
(1.3)
(1.3) TYP
(5.8)
( ) TYP
VIA
0.2
(0.65) TYP
4214870/A 10/2014
PowerPAD - 1.1 mm max heightPWP0028A
PLASTIC SMALL OUTLINE
SOLDER MASK
DEFINED PAD
LAND PATTERN EXAMPLE
SCALE:6X
HV / ISOLATION OPTION
0.9 CLEARANCE CREEPAGE
OTHER DIMENSIONS IDENTICAL TO IPC-7351
TM
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
8. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
numbers SLMA002 (www.ti.com/lit/slma002) and SLMA004 (www.ti.com/lit/slma004).
9. Size of metal pad may vary due to creepage requirement.
METAL
SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
SOLDER MASK DETAILS
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
SYMM
SYMM
SEE DETAILS
1
14 15
28
METAL COVERED
BY SOLDER MASK
SOLDER
MASK
OPENING
IPC-7351 NOMINAL
0.65 CLEARANCE CREEPAGE
www.ti.com
EXAMPLE STENCIL DESIGN
28X (1.3)
28X (0.45)
(6.1)
28X (1.5)
28X (0.45)
26X (0.65)
(3)
(5.5)
BASED ON
0.127 THICK
STENCIL
(5.8)
4214870/A 10/2014
PowerPAD - 1.1 mm max heightPWP0028A
PLASTIC SMALL OUTLINE
2.66 X 4.770.178
2.88 X 5.160.152
3.0 X 5.5 (SHOWN)0.127
3.55 X 6.370.1
SOLDER STENCIL
OPENING
STENCIL
THICKNESS
SEE TABLE FOR
DIFFERENT OPENINGS
FOR OTHER STENCIL
THICKNESSES
NOTES: (continued)
10. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
11. Board assembly site may have different recommendations for stencil design.
TM
SOLDER PASTE EXAMPLE
EXPOSED PAD
100% PRINTED SOLDER COVERAGE AREA
SCALE:6X
HV / ISOLATION OPTION
0.9 CLEARANCE CREEPAGE
OTHER DIMENSIONS IDENTICAL TO IPC-7351
SYMM
SYMM
1
14 15
28
BASED ON
0.127 THICK
STENCIL BY SOLDER MASK
METAL COVERED
IPC-7351 NOMINAL
0.65 CLEARANCE CREEPAGE
MECHANICAL DATA
NJB0028A
www.ti.com
LQA28A (REV B)
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