LM4780TA/NOPB National Semiconductor, LM4780TA/NOPB Datasheet

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... The LM4780 can easily be configured for bridge or parallel operation for 120W mono solutions. Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit Overture ® registered trademark of National Semiconductor. © 2010 National Semiconductor Corporation LM4780 Overture ™ Audio Power Amplifier Series Key Specifications ■  ...

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Connection Diagrams www.national.com (Note 14) Plastic Package Top View Order Number LM4780TA See NS Package Number TA27A TO-220 Top Marking Top View U - Wafer Fab Code Z - Assemble Plant Code XY - Date Code TT - Die Run ...

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... Absolute Maximum Ratings 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage | (No Signal) Supply Voltage | (Input Signal) Common Mode Input Voltage Differential Input Voltage (Note 13) Output Current Power Dissipation (Note ...

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Symbol Parameter Common Mode Rejection Ratio CMRR (Note 15) A Open Loop Voltage Gain VOL GBWP Gain Bandwidth Product e Input Noise IN SNR Signal-to-Noise Ratio IMD Intermodulation Distortion Note 1: All voltages are measured with respect to the ground ...

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Bridged Amplifier Application Circuit FIGURE 2. Bridged Amplifier Application Circuit 5 20058614 www.national.com ...

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Parallel Amplifier Application Circuit www.national.com FIGURE 3. Parallel Amplifier Application Circuit 6 20058613 ...

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Single Supply Application Circuit *Optional components dependent upon specific design requirements. FIGURE 4. Single Supply Amplifier Application Circuit Auxiliary Amplifier Application Circuit FIGURE 5. Special Audio Amplifier Application Circuit 20058606 200586d5 7 www.national.com ...

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External Components Description (Figures 1-5) Components Prevents current from entering the amplifier's non-inverting input. This current may pass through to the load R during system power down, because of the amplifier's low input impedance when the undervoltage circuitry is 1 ...

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Optional External Component Interaction The optional external components have specific desired func- tions. Their values are chosen to reduce the bandwidth and eliminate unwanted high frequency oscillation. They may, however, cause certain undesirable effects when they inter- act. Interaction may ...

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THD+N vs Output Power/Channel = 6Ω, 80kHz BW ± 30V Output Power/Channel vs Supply Voltage = 4Ω, 80kHz 1kHz www.national.com THD+N vs Output Power/Channel ± 35V, R 200586e9 Output Power/Channel vs Supply Voltage ...

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Output Power/Channel vs Supply Voltage = 8Ω, 80kHz 1kHz Total Power Dissipation vs Output Power/Channel = 6Ω, 80kHz BW 1% THD (max Total Power Dissipation vs Output Power/Channel 1% THD (max), R 20058623 ...

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Crosstalk vs Frequency ± 25V 10W OUT = 4Ω, 80kHz Mute Attenuation vs Mute Pin Current P = 10W/Channel OUT Large Signal Response www.national.com Crosstalk vs Frequency ± 35V 200586c5 vs Supply Voltage ...

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Common Mode Rejection Ratio 200586c9 Clipping Voltage vs Supply Voltage 200586d1 THD+N vs Frequency ± 25V & 50W OUT = 8Ω, 80kHz BW Bridge Mode (Note 18 Open Loop Frequency Response Clipping Voltage vs Supply ...

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THD+N vs Output Power ± 25V, Bridge Mode (Note 18) = 8Ω, 80kHz Output Power vs Supply Voltage, Bridge Mode (Note 18) = 8Ω, 80kHz 1kHz Safe Area www.national.com THD+N vs Output ...

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Frequency Response of Demo Board P = 10W/Channel = 0dB OUT = 8Ω, No Filters R = 47kΩ Note 18: Bridge mode graphs were taken using the demo board and inverting the signal to the channel B ...

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Application Information MUTE MODE The muting function allows the user to mute the amplifier. This can be accomplished as shown in the Typical Application Cir- cuit. The resistor R is chosen with reference to the negative M supply voltage and ...

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DETERMINING THE CORRECT HEAT SINK The choice of a heat sink for a high-power audio amplifier is made entirely to keep the die temperature at a level such that the thermal protection circuitry is not activated under normal circumstances. The ...

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P the correct heat sink size can be determined. Refer to DMAX the section, Determining the Correct Heat Sink, for more information and detailed discussion of proper heat sinking. SINGLE-SUPPLY AMPLIFIER APPLICATION The typical application of the LM4780 is a ...

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Integrated circuits have additional open loop gain allowing additional feedback loop gain in order to lower harmonic dis- tortion and improve frequency response this additional bandwidth that can lead to erroneous signal-to-noise mea- surements if not considered during ...

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The load current I will be much larger than input bias current thus V will follow the output voltage directly, i.e. in phase Therefore the voltage appearing at the non-inverting input is effectively positive feedback ...

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FIGURE 6. Inverting Amplifier Application Circuit 21 20058621 www.national.com ...

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FIGURE 7. Reference PCB Schematic 22 200586f3 ...

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LM4780 REFERENCE BOARD ARTWORK Composite Layer Top Layer 200586d9 Silk Layer 200586d7 Bottom Layer 23 200586d8 200586e0 www.national.com ...

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Bill Of Materials For Reference Pcb Symbol Value 15kΩ IN1 IN2 1kΩ 20kΩ 1kΩ 2.7Ω SN1 SN2 2.7Ω ...

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Physical Dimensions inches (millimeters) unless otherwise noted Non-Isolated TO-220 27-Lead Package Order Number LM4780TA NS Package Number TA27A 25 www.national.com ...

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... For more National Semiconductor product information and proven design tools, visit the following Web sites at: www.national.com Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock and Timing www.national.com/timing Data Converters www.national.com/adc Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www.national.com/ldo LED Lighting www ...