LM4842MH NSC [National Semiconductor], LM4842MH Datasheet
LM4842MH
Related parts for LM4842MH
LM4842MH Summary of contents
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... Note 1: When properly mounted to the circuit board, the LM4842MH will deliver 2W into 4Ω. The LM4842MT will deliver 1.1W into 8Ω. See the Application Information section for LM4842MH usage information. Note 2: An LM4842MH that has been properly mounted to the circuit board and forced-air cooled will deliver 2.2W into 3Ω. Connection Diagrams ...
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Connection Diagrams See NS Package Number LQA028AA for Exposed-DAP LLP www.national.com (Continued) LM4842LQ Pinout Top View Order Number LM4842LQ 2 200281A3 ...
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3 www.national.com ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage Storage Temperature Input Voltage Power Dissipation (Note 11) ESD Susceptibility (Note 12) All pins except Pin 28 ...
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Electrical Characteristics for Single-Ended Mode Operation 10) (Continued) The following specifications apply for V Symbol Parameter THD+N Total Harmonic Distortion+Noise PSRR Power Supply Rejection Ratio SNR Signal to Noise Ratio X Channel Separation talk Electrical Characteristics for Bridged Mode Operation ...
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... Figure 2. Note 8: When driving 3Ω loads from a 5V supply the LM4842MH and LM4842LQ exposed DAP must be soldered to the circuit board and forced-air cooled. Note 9: When driving 4Ω loads from a 5V supply the LM4842MH and LM4842LQ exposed DAP must be soldered to the circuit board. ...
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7 www.national.com ...
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... A0 & B0 Vol. Adjustable off A0 & B0 Muted on A1 & B1 Vol. Adjustable off A1 & B1 Muted on A0 & B0 Vol. Adjustable off A1 & B1 Muted muted X Muted THD+N vs Frequency 20028170 THD+N vs Frequency 20028172 8 Single-Ended Output - Vol. Adjustable - Vol. Adjustable - Vol. Adjustable Muted LM4842MH/LQ 20028171 LM4842MH/LQ 20028173 ...
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... Typical Performance Characteristics MH/LQ Specific Characteristics LM4842MH/LQ Power Dissipation vs Output Power Note 17: These curves show the thermal dissipation ability of the LM4842MH/LQ at different ambient temperatures given these conditions: 2 500LFPM + 2in : The part is soldered to a 2in 2 2in on bottom: The part is soldered to a 2in 2 2 2in : The part is soldered to a 2in , 1oz ...
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Non-MH/LQ Specific Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency www.national.com (Continued) THD+N vs Frequency 20028114 THD+N vs Frequency 20028116 THD+N vs Frequency 20028118 10 20028115 20028117 20028119 ...
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Non-MH/LQ Specific Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Output Power (Continued) THD+N vs Frequency 20028120 THD+N vs Output Power 20028122 THD+N vs Output Power 20028125 11 20028121 20028124 20028126 www.national.com ...
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Non-MH/LQ Specific Characteristics THD+N vs Output Power THD+N vs Output Power THD+N vs Output Power www.national.com (Continued) THD+N vs Output Power 20028127 THD+N vs Output Power 20028129 THD+N vs Output Power 20028131 12 20028128 20028130 20028132 ...
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Non-MH/LQ Specific Characteristics THD+N vs Output Power THD+N vs Output Voltage Docking Station Pins Output Power vs Load Resistance (Continued) THD+N vs Output Power 20028133 THD+N vs Output Voltage Docking Station Pins 20028159 20028162 13 20028134 20028160 Output Power vs ...
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Non-MH/LQ Specific Characteristics Output Power vs Load Resistance Dropout Voltage Power Supply Rejection Ratio www.national.com (Continued) Output Power vs Load Resistance 20028107 Power Dissipation vs 20028153 Volume Control Characteristics 20028135 14 20028108 Output Power 20028151 20028136 ...
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Non-MH/LQ Specific Characteristics Power Dissipation vs Output Power Power Derating Curve Output Power vs Supply voltage (Continued) External Gain/Bass Boost 20028152 20028163 vs Supply Voltage 20028154 15 Characteristics 20028161 Crosstalk 20028149 Output Power 20028156 www.national.com ...
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Non-MH/LQ Specific Characteristics www.national.com (Continued) Supply Current vs Supply Voltage 20028109 16 ...
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Application Information ELIMINATING OUTPUT COUPLING CAPACITORS Typical single-supply audio amplifiers that can switch be- tween driving bridge-tied-load (BTL) single-ended (SE) headphones use a coupling capacitor on each SE output. This capacitor blocks the half-supply volt- age to which the output ...
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... If the heatsink and amplifier share the same PCB layer, a nominal 2.5in necessary for 5V operation with a 4Ω load. Heatsink areas not placed on the same PCB layer as the LM4842MH and 2 LQ packages should be 5in (min) for the same supply voltage and load resistance. The last two area recommen- dations apply for 25˚ ...
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... DAP pad that expands to a copper area of 5in PCB, the LM4842’s θ = 20˚C/W. In the MH and LQ pack- JA ages soldered to a DAP pad that expands to a copper area on a PCB, the LM4842MH’s and LQ’s θ 2in For the LM4842MT package, θ = 80˚C/W. At any given ...
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Application Information As an example when using a speaker with a low frequency limit of 150Hz, the input coupling capacitor using Equation (7), is 0.053µF. The 0.33µF input coupling capacitor shown in Figure 1 allows the LM4842 to drive high ...
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Application Information The BEEP IN pin is used only to detect the beep signal’s magnitude: it does not pass the signal to the output amplifi- CAP-LESS HEADPHONE (SINGLE-ENDED) AMPLIFIER OPERATION An internal pull−up circuit is connected to the HP Sense ...
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Application Information to ground to enable shutdown system with a micropro- cessor or a microcontroller, use a digital output to apply the control voltage to the SHUTDOWN pin. BASS BOOST The ’Bass Boost Mode’ is enabled whenever the ...
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Volume Control Table ( Table 2 ) Gain Voltage Range (% of Vdd) (dB) Low High Recommended Low 0 77.5% 100.00% 100.000% -1 75.0% 78.5% 76.875% -2 72.5% 76.25% 74.375% -3 70.0% 73.75% 71.875% -4 67.5% 71.25% 69.375% -5 65.0% ...
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Audio Power Amplifier Design AUDIO AMPLIFIER DESIGN: DRIVING 1W INTO AN 8Ω LOAD The following are the desired operational parameters: Power Output: Load Impedance: Input Level: Input Impedance: Bandwidth: 100 Hz−20 kHz The design begins by specifying the minimum supply ...
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Recommended Printed Circuit Board Layout - MH/MT Packages FIGURE 7. Top Layer SilkScreen - ( Not to Scale ) FIGURE 8. Top Layer - ( Not to Scale ) 25 20028193 20028195 www.national.com ...
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Recommended Printed Circuit Board Layout - MH/MT Packages www.national.com FIGURE 9. Bottom Layer - ( Not to Scale ) FIGURE 10. Top Layer SilkScreen - ( Not to Scale ) 26 (Continued) 20028194 200281A2 ...
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Recommended Printed Circuit Board Layout - LQ Package FIGURE 11. Top Layer - ( Not to Scale ) FIGURE 12. Bottom Layer - ( Not to Scale ) 27 200281A1 200281A0 www.national.com ...
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Item Part Number Part Description 1 551011373-001 LM4842 Eval Board PCB etch 001 10 482911373-001 LM4842 TSSOP 151911368-001 Cer Cap 0.068µF 50V 10% 1206 25 152911368-001 Tant Cap 0.1µF 10V 10% Size = A 3216 26 152911368-002 ...
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Physical Dimensions inches (millimeters) unless otherwise noted TSSOP Package Order Number LM4842MT NS Package Number MTC28 for TSSOP 29 www.national.com ...
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... Physical Dimensions NS Package Number MXA28A for Exposed-DAP TSSOP www.national.com inches (millimeters) unless otherwise noted (Continued) Exposed-DAP TSSOP Package Order Number LM4842MH 30 ...
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Physical Dimensions NS Package Number LQA28A for Exposed-DAP LLP LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF ...