lm4874mh National Semiconductor Corporation, lm4874mh Datasheet
lm4874mh
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lm4874mh Summary of contents
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... Thermal shutdown protection circuit n Ultra low current micropower shutdown mode n 3.0V to 5.5V operation n Available in space-saving exposed-DAP TSSOP package Applications 2.1W (typ) n Notebook computers n PDAs n Portable electronic devices 1.9W (typ) Top View Order Number LM4874MH DS200469 August 2002 = 5.0V, and THD 1.2W (typ) 0.1µA (typ) = 5V, (Fig.1)) 62dB (typ) DD 20046902 www.national.com ...
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Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit www.national.com 2 20046901 ...
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... Input Resistance IN Note 1: An LM4874MH that has been properly mounted to a circuit board with a copper heatsink area of at least 2in Note 2: All voltages are measured with respect to the GND pin unless other wise specified. Note 3: 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 guarantee specific performance limits ...
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... Note 10: Datasheet minimum and maximum specification limits are guaranteed by design, test, or statistical analysis. Note 11: Output power is measured at the amplifier’s package pins. Note 12: When driving 3Ω or 4Ω loads and operating supply, the LM4874MH must be mounted to a circuit board that has a minimum of 2in uninterrupted copper area connected to the MH package’s exposed DAP. ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Frequency 8Ω OUT at (from top to bottom at 1kHz 21.6dB 15.6dB 10dB 6dB ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Output Power 4Ω (from top to bottom at 100mW 21.6dB 15.6dB 6dB 10dB ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Output Power 8Ω (from top to bottom at 200mW 21.6dB 15.6dB 10dB ...
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Typical Performance Characteristics MH Specific Characteristics PSRR vs Frequency 4Ω SOURCE V = 200mV , at (from top to bottom at 1kHz): RIPPLE P 21.6dB 15.6dB ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Output Power 4Ω (from top to bottom at 200mW 21.6dB 6dB 15.6dB ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Output Power 8Ω (from top to bottom at 200mW 21.6dB 15.6dB 6dB 10dB ...
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Typical Performance Characteristics MH Specific Characteristics Output Power vs Load Resistance f = 1kHz, at (from top to bottom at 20Ω): 5V, THD = 10 5V, THD = 1 3V, THD ...
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Typical Performance Characteristics MH Specific Characteristics Dropout Voltage vs Power Supply Voltage R = 4Ω 1kHz, both channels driven and loaded (from top to bottom at 4V): positive signal swing, negative signal swing Amplifier Power ...
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Typical Performance Characteristics MH Specific Characteristics Cross Talk vs Frequency 8Ω Left channel driven, right channel measured Right channel driven, left channel measured Cross Talk vs Frequency ...
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Typical Performance Characteristics MH Specific Characteristics Cross Talk vs Frequency 8Ω Left channel driven, right channel measured Right channel driven, left channel measured www.national.com (Continued) 200469D4 = 10dB, ...
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Application Information PCB LAYOUT AND SUPPLY REGULATION CONSIDERATIONS FOR DRIVING 3W AND 4W LOADS Power dissipated by a load is a function of the voltage swing across the load and the load’s impedance. As load imped- ance decreases, load dissipation ...
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Application Information Table 1. Gain Settings and Input Resistance GAIN 0 GAIN 1 Selected Gain (dB 15 21.6 POWER SUPPLY BYPASSING As with any power amplifier, proper supply bypassing is ...
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Application Information Bypass Capacitor Value Selection Besides optimizing the input capacitor value, careful consid- eration should be paid to value nected between the BYPASS pin and ground. Since C determines how fast the LM4874 settles to its ...
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Application Information As mentioned in the External Components section, the inter- nal input resistor and C create a high pass filter that sets the i amplifier’s lower bandpass frequency limit. Find the coupling capacitor’s value using Equation (11 ...
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Recommended Printed Circuit Board Layout FIGURE 4. Recommended MH PC Board Layout: FIGURE 5. Recommended MH PC Board Layout: FIGURE 6. Recommended MH PC Board Layout: (Continued) 200469D9 Upper Inner-Layer Layout 200469E0 Lower Inner-Layer Layout 200469E1 Bottom-Side Layout 19 www.national.com ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) unless otherwise noted Exposed-DAP TSSOP Package Order Number LM4874MH 2. A critical component is any component of a life support device or system whose failure to perform ...