LM4991LD National Semiconductor, LM4991LD Datasheet
LM4991LD
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LM4991LD Summary of contents
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... Additional LM4991 features include thermal shutdown pro- tection, unity-gain stability, and external gain set. Note 1: An LM4991LD that has been properly mounted to a circuit board will deliver 3W into 3Ω (at 10% THD). The other package options for the LM4991 will deliver 1.5W into 8Ω (at 10% THD). See the Application Information sections for further information concerning the LM4991LD and LM4991M ...
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Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit www.national.com 2 20074001 ...
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... THD = 1% (max 1kHz LM4991LD 3Ω (Note 10) L LM4991LD 4Ω (Note 10) L LM4991 8Ω L THD 1kHz LM4991LD 3Ω (Note 10) L LM4991LD 4Ω (Note 10) L LM4991 8Ω 0.5W 1kHz 200mV sine p-p, RIPPLE Input terminated with 10Ω 1kHz ...
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... Note 8: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level). Note 9: The given θ is for an LM4991 packaged in an LDC08A with the Exposed–DAP soldered to an exposed 1in JA Note 10: When driving 3Ω or 4Ω loads from a 5V supply, the LM4991LD must be mounted to a circuit board. www.national.com = 3V (Notes 2, 3) ...
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External Components Description (Figure 1) Components 1. R Inverting input resistance that sets the closed-loop gain in conjunction with R i pass filter with Input coupling capacitor that blocks the DC voltage at the ...
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Typical Performance Characteristics THD+N vs Frequency 8Ω, and THD+N vs Frequency V = 2.6V 8Ω, and THD+N vs Output Power 4Ω, and ...
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Typical Performance Characteristics THD+N vs Output Power V = 2.6V 4Ω, and f = 1kHz DD L Power Supply Rejection Ratio (PSRR) vs Frequency 8Ω, input 10Ω terminated DD L Power Supply Rejection ...
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Typical Performance Characteristics Power Supply Rejection Ratio (PSRR) vs Frequency V = 2.6V 8Ω, input 10Ω terminated DD L Open Loop Frequency Response, 5V Power Dissipation vs Output Power www.national.com (Continued) Power Supply Rejection Ratio (PSRR) ...
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Typical Performance Characteristics Power Dissipation vs Output Power 2.6V DD Shutdown Hysteresis Voltage V = 3V, SD Mode = V DD Output Power vs Supply Voltage (Continued) 20074063 DD 20074073 = 4Ω 20074067 9 Shutdown Hysteresis ...
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Typical Performance Characteristics Output Power vs Supply Voltage, R Frequency Response vs Input Capacitor Size Application Information EXPOSED-DAP PACKAGE PCB MOUNTING CONSIDERATION The LM4991’s exposed-DAP (die attach paddle) package (LD) provides a low thermal resistance between the die and the ...
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Application Information LD (LLP) package is available from National Semiconduc- tor’s Package Engineering Group under application note AN1187. PCB LAYOUT AND SUPPLY REGULATION CONSIDERATIONS FOR DRIVING 3Ω AND 4Ω LOADS Power dissipated by a load is a function of the ...
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Application Information connected between the bypass pin and ground improves the internal bias voltage’s stability, producing improved PSRR. The improvements to PSRR increase as the bypass pin capacitor increases. Typical applications employ a 5V regu- lator with 10µF and a ...
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Application Information must make sure that the power supply choice along with the output impedance does not violate the conditions explained in the Power Dissipation section. Once the power dissipation equations have been addressed, the required differential gain can be ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted Order Number LM4991LD See NS Package Number LDC08A Order Number LM4991MA NS Package Number M08A 14 ...
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... 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 NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...