LM4681 National Semiconductor, LM4681 Datasheet
LM4681
Related parts for LM4681
LM4681 Summary of contents
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... With a 8Ω load, the IC’s efficiency for a 6W power level is 85%. The IC features click and pop reduction circuitry that minimizes audible popping during device turn-on and turn- off. The LM4681 is available in a 48-lead LLP package, ideal for portable and desktop computer applications. Block Diagram BOOMER ™ ...
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... Connection Diagram www.national.com LLP Package Top View Order Number LM4681SQ See NS Package Number SQA048AA (LLP Package) 2 20118917 ...
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... 1W/Chan 1kHz 50Ω 1µF, SOURCE 8Hz to 22kHz, A-weighted, input referred 4 (Notes 1, 2) ≤ T −40˚C ≤ T ≤ +85˚C A MAX A 9V ≤ LM4681 Typical Limit 15 0.1 8 5 – ...
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... Power Amplifier Headphone Amplifier Digital Code = 0, No Load Power Amplifier Headphone Amplifier 5 LM4681 Typical Limit 0.02 = 32Ω 32Ω LM4681 Typical Limit (Note 8) (Note –48 –46 –65 –63 –74 –76 –74 www.national.com Units dB mW (min) % µ ...
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I C/SPI Interface Controls Address Mode Control Register Volume Control Register (See Table 4 ) Headphone Control HP Sense Pin (HPSEL, pin 22) 0 ...
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Typical Performance Characteristics (Volume control at maximum, unless otherwise stated.) Class D Amplifier THD+N vs Frequency 8Ω Class D Amplifier THD+N vs Frequency V = 15.5V 8Ω ...
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Typical Performance Characteristics Class D Amplifier THD+N vs Output Power 8Ω Both channel driven, both measured Class D Amplifier THD+N vs Output Power V = 15.5V Both channel driven, both ...
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Typical Performance Characteristics Class D Amplifier Output Power vs Supply Voltage Class D Amplifier Magnitude vs Frequency 8Ω Class D Amplifier Magnitude vs Frequency V = 15.5V 8Ω, P ...
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Typical Performance Characteristics Class AB Headphone Amplifier Magnitude vs Frequency V = 12V 32Ω PSRR vs Frequency PSRR vs Frequency V = 15.5V DD www.national.com (Continued) Class AB Headphone Amplifier Magnitude ...
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Typical Performance Characteristics Class D Amplifier Dissipation vs Load Dissipation V = 12V 8Ω Both channels driven and measured Class D Amplifier Efficiency vs Total Output Power 8Ω Both ...
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Typical Performance Characteristics Output Power vs Load Resistance V = 12V, DD Upper curve = 10% THD+N, Lower curve = 1% THD+N Power Supply Current vs Power Supply Voltage www.national.com (Continued) Output Power vs Load Resistance Upper curve = 10% ...
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... LM4681’s Class D amplifiers. Under Voltage Proctection The under voltage protection disables the output driver sec- tion of the LM4681 while the supply voltage is below 8V. This condition may occur as power is first applied or during low line conditions, changes in load resistance, or when power supply sag occurs. The under voltage protection ensures that all of the LM4681’ ...
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... After the data byte is sent, the master must check for another acknowledge to see if the LM4681 received the data. If the master has more data bytes to send to the LM4681, then the master can repeat the previous two steps until all data bytes have been sent. ...
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General Features (Continued Timing Diagrams SPI Timing Diagram SPI Operational Requirements 1. The maximum clock rate is 5MHz for the CLK pin. 2. CLK must remain logic-high for at least 100ns (t the rising edge of CLK, ...
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General Features (Continued ENABLE is logic-low for more than 8 CLK pulses then only the first 8 data bits will be latched and activated at rising edge of eighth CLK. 9. ENABLE must remain logic-high for at least ...
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... SV pin. DD OUTPUT STAGE FILTERING The LM4681 requires a low pass filter connected between the amplifier’s bridge output and the load. Figure 1 shows the recommended LC filter. A minimum value of 27µH is recommended. As shown in Figure 1, using the values of the components connected between the amplifier BTL outputs and the load achieves a 2nd-order lowpass filter response with a -3dB cutoff frequency of 25kHz ...
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Revision History Rev 1.0 1.1 1.2 1.3 www.national.com Date 2/09/06 2/10/06 Edited the PSRR Typical values in the Elect. Char table. 3/08/06 Did few texts (Gen Desc section) clean-up, then re-released 3/17/06 Changed the typo under PSRR (Conditions-Vripple from 20mVp-p ...
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... Deutsch Tel: +49 (0) 69 9508 6208 English www.national.com Français Tel: +33 ( 8790 Order Number LM4681SQ NS Package Number SQA048AA 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness ...