LM4938MHX/NOPB National Semiconductor, LM4938MHX/NOPB Datasheet
LM4938MHX/NOPB
Specifications of LM4938MHX/NOPB
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LM4938MHX/NOPB Summary of contents
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... PCB Mounting Considerations for more information. Note 2: An LM4938MH that has been properly mounted to the circuit board and forced-air cooled will deliver 2.2W into 3Ω. Block Diagram Boomer ® registered trademark of NationalSemiconductor Corporation. © 2005 National Semiconductor Corporation Key Specifications THD+N O into 3Ω n into 4Ω ...
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Connection Diagram See NS Package Number MXA28A for Exposed-DAP TSSOP www.national.com TSSOP Package 20095602 Top View Order Number LM4938MH 2 ...
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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) ESD Susceptibility (Note 13) Junction Temperature Soldering Information Small Outline Package Vapor Phase (60 sec ...
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Electrical Characteristics for Bridged Mode Operation The following specifications apply for V Symbol Parameter P Output Power O THD+N Total Harmonic Distortion + Noise PSRR Power Supply Rejection Ratio SNR Signal to Noise Ratio X Channel Separation talk Electrical Characteristics ...
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Electrical Characteristics for Single-Ended Mode Operation 10) (Continued) Note 3: The θ given is for an MXA28A package whose exposed-DAP is soldered to an exposed 2in JA Note 4: The θ given is for an MXA28A package whose exposed-DAP is ...
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Typical Application Truth Table for Logic Inputs Gain Mode Headphone Sel Sense ...
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Typical Performance Characteristics THD+N vs Output Power 4Ω 1kHz DD L THD+N vs Output Power 32Ω, SE 1kHz DD L THD+N vs Output Power V = ...
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Typical Performance Characteristics THD+N vs Output Power 32Ω, SE 1kHz DD L THD+N vs Frequency 4Ω THD+N vs Frequency 32Ω, ...
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Typical Performance Characteristics THD+N vs Frequency 4Ω 600mW Frequency Response 4Ω Frequency Response 32Ω ...
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Typical Performance Characteristics Frequency Response 4Ω Frequency Response 32Ω PSRR vs Frequency 8Ω, Unterminated DD L www.national.com (Continued) ...
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Typical Performance Characteristics PSRR vs Frequency 32Ω, Unterminated DD L PSRR vs Frequency 8Ω, Unterminated DD L PSRR vs Frequency 32Ω, Unterminated ...
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Typical Performance Characteristics Crosstalk vs Frequency 32Ω Crosstalk vs Frequency 32Ω Power Derating Curve (Note 17) www.national.com (Continued) = 30mW, SE 20095610 ...
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Typical Performance Characteristics Power Dissipation vs Output Power Power Dissipation vs Output Power (Continued) Bass Boost Characteristics 20095665 Power Dissipation vs 20095651 13 External Gain/ 20095661 Output Power 20095652 www.national.com ...
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Typical Performance Characteristics Note 17: These curves show the thermal dissipation ability of the LM4938MH at different ambient temperatures given these conditions: 2 500LFPM + 2in : The part is soldered to a 2in 2 2in on bottom: The part ...
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... TSSOP are shown in the Demonstra- tion Board Layout section. Further detailed and specific information concerning PCB layout, fabrication, and mount- ing a package is available in National Semiconductor’s AN1187. PCB LAYOUT AND SUPPLY REGULATION CONSIDERATIONS FOR DRIVING 3Ω AND 4Ω LOADS Power dissipated by a load is a function of the voltage swing across the load and the load’ ...
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Application Information The LM4938 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 ampli- fier. From Equation (3), assuming a 5V power supply and ...
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Application Information through the feedback resistor Thus, pops can be mini- f mized by selecting an input capacitor value that is no higher than necessary to meet the desired −6dB frequency. As shown in Figure 2, the input ...
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Application Information MICRO-POWER SHUTDOWN The voltage applied to the SHUTDOWN pin controls the LM4938’s shutdown function. Activate micro-power shut- down by applying V to the SHUTDOWN pin. When active, DD the LM4938’s micro-power shutdown feature turns off the amplifier’s bias ...
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Application Information GAIN SELECT FUNCTION (Bass Boost) The LM4938 features selectable gain, using either internal or external feedback resistors. Either set of feedback resistors set the gain of the output amplifiers. The voltage applied to the GAIN SELECT pin controls ...
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Application Information VOLUME CONTROL TABLE ( Table 2 ) Gain Voltage Range (% of Vdd) (dB) Low High Recommended 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 ...
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Application Information 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 ...
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Recommended Printed Circuit Board Layout www.national.com (Continued) FIGURE 5. Top Layer Silkscreen FIGURE 6. Top Layer TSSOP 22 20095682 20095683 ...
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Recommended Printed Circuit Board Layout (Continued) FIGURE 7. Inner Layer (2) FIGURE 8. Inner Layer (3) 23 20095685 20095686 www.national.com ...
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Recommended Printed Circuit Board Layout www.national.com (Continued) FIGURE 9. Bottom Layer TSSOP 24 20095684 ...
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Item Part Number 1 551011373-001 10 482911373-001 20 151911368-001 25 152911368-001 26 152911368-002 27 152911368-003 28 152911368-004 29 152911368-005 30 472911368-001 31 472911368-002 32 472911368-003 33 472911368-004 40 131911368-001 41 131911368-002 42 131911368-003 43 131911368-004 44 131911368-005 45 131911368-006 Analog ...
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Revision History Rev 1.0 www.national.com Date Description 7/15/05 Added f = 1kHz to the titles on A2, A3, A4, A5, A6, A7, and A8. Re-released D the WEB. ...
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