LM4869 NSC [National Semiconductor], LM4869 Datasheet
LM4869
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LM4869 Summary of contents
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... BTL load (Note 1), respectively, with less than 1% THD+N. The LM4869’s gain is selected using two digital inputs. The nomi- nal gain values are 6dB, 10dB, 15.6dB, and 21.6dB. The LM4869 is designed for notebook and other handheld portable applications ...
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Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit www.national.com 2 20042801 ...
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... ESD Susceptibility (Note 6) Junction Temperature Soldering Information Small Outline Package Vapor Phase (60 sec.) Electrical Characteristics for LM4869 The following specifications applies to the LM4869 when used in the circuit shown in Figure 1 and operating with 6dB, unless otherwise specified. Limits apply for T V Symbol Parameter ...
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... Note 11: Datasheet minimum and maximum specification limits are guaranteed by design, test, or statistical analysis. Note 12: Output power is measured at the amplifier’s package pins. Note 13: When driving 4Ω loads and operating supply, the LM4869MH must be mounted to a circuit board that has a minimum of 2.5in uninterrupted copper area connected to the LLP package’s exposed DAP. ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Frequency 4Ω 1000mW OUT at (from top to bottom at 1kHz 21.6dB 15.6dB 10dB, A ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Output Power 4Ω (from top to bottom at 200mW 21.6dB 15.6dB 10dB 6dB ...
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Typical Performance Characteristics MH Specific Characteristics THD vs Output Power 8Ω 20kHz (from top to bottom at 200mW 21.6dB 15.6dB 10dB, ...
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Typical Performance Characteristics MH Specific Characteristics PSRR vs Frequency 8Ω 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 100mW 21.6dB 15.6dB 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 10dB ...
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Typical Performance Characteristics MH Specific Characteristics Channel-to-Channel gain Mismatch vs Power Supply Voltage R = 4Ω 1kHz (from top to bottom at 4V 21.6dB 15.6dB 10dB, A ...
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Typical Performance Characteristics MH Specific Characteristics Amplifier Power Dissipation vs Amplifier Load Dissipation 1kHz, at (from top to bottom at 1W 4Ω 8Ω, single channel driven and loaded L ...
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Typical Performance Characteristics MH Specific Characteristics Cross Talk vs Frequency 8Ω 15.6dB Left channel driven, right channel measured Right channel driven, left channel measured Cross Talk ...
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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 (from top to bottom at ...
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... The capacitors connected to the bypass and power supply pins should be placed as close to the LM4869 as possible. The capacitor connected between the bypass pin and ground improves the internal bias voltage’s stability, producing improved PSRR ...
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... RMS P-P supply voltage is ramping to its final value, the LM4869’s internal amplifiers are configured as unity gain buffers. An internal current source changes the voltage of the BYPASS pin in a controlled, linear manner. Ideally, the amplifier inputs and outputs track the voltage applied to the BYPASS pin. ...
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... Thus, a minimum gain of 2.83 allows the LM4869’s to reach 210ms full output swing and maintain low noise and THD+N perfor- mance. For this example, let A the gain will be set to 10dB (A low to GAIN 0 and a logic high to GAIN 1. may not DD The last step in this design example is setting the amplifier’ ...
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... RECOMMENDED PRINTED CIRCUIT BOARD LAYOUT Figures 2 through 6 show the recommended four-layer PC board layout that is optimized for the 20-pin MH-packaged LM4869 and associated external components. This circuit is designed for use with an external 5V supply and 3Ω (or higher) speakers (or load resistors). This circuit board is easy to use. Apply 5V and ground to the board’s V load resistors) between the board’ ...
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FIGURE 6. Recommended MH PC Board Layout: Bottom-Side Layout 19 200428E1 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 LM4869MH 2. A critical component is any component of a life support device or system whose failure to perform ...