LM4981 National Semiconductor, LM4981 Datasheet
LM4981
Related parts for LM4981
LM4981 Summary of contents
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... Eliminating the output capacitors also improves low fre- quency response. The LM4981 operates from a single 2.0V – 4.2V supply, and features a 2-wire, up/down volume control that sets the gain of the amplifier between -33dB to +12dB in 16 discrete steps ...
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... Connection Diagrams www.national.com LLP Package 20147338 Top View Order Number LM4981SQ See NS Package Number SQA16A LLP Marking 20147321 Top View U = Plant Code ZX = Date Code X = Die Traceability Bottom Line = Part Number 2 ...
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Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit Pin Name CP VDD CCP+ Positive Terminal- charge pump flying capacitor PGND CCP- Negative Terminal- ...
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... Cl = 1µ 200mV Sine, RIPPLE P 10kHz, Inputs AC GND, RIPPLE Cl = 1µ 200mV Sine, RIPPLE P 217Hz RIPPLE A-Weighted Filter 4 ≤ T −40˚C ≤ MAX A 2.0V ≤ LM4981 (Limits) Typical Limit (Note 6) (Note 2.3 0.1 3.5 0. –33 3 ± 0.3 0.15 300 (min) ...
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Electrical Characteristics V Note 1: All voltages are measured with respect to the GND pin unless other wise specified Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which ...
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Typical Performance Characteristics THD+N vs Frequency V = 1.8V 16Ω THD+N vs Frequency 16Ω THD+N vs Frequency V = 3.6V 16Ω www.national.com ...
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Typical Performance Characteristics THD+N vs Frequency V = 4.2V 16Ω THD+N vs Output Power V = 1.8V 16Ω 1kHz, one channel DD L THD+N vs Output Power V = 1.8V, ...
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Typical Performance Characteristics THD+N vs Output Power 16Ω 1kHz, one channel DD L THD+N vs Output Power 32Ω 1kHz, one channel DD L THD+N vs Output ...
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Typical Performance Characteristics THD+N vs Output Power V = 3.6V 32Ω 1kHz, one channel DD L THD+N vs Output Power V = 4.2V 16Ω 1kHz, one channel DD L THD+N vs Output ...
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Typical Performance Characteristics Output Power vs Supply Voltage R = 16Ω 1kHz, one channel L Output Power vs Supply Voltage R = 32Ω 1kHz, one channel L Supply Current vs Supply Voltage www.national.com (Continued) Output Power ...
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Typical Performance Characteristics Power Dissipation vs Output Power R = 32Ω (Continued) PSRR vs Frequency V 20147382 32Ω 200mVp-p ripple 20147383 www.national.com ...
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... ELIMINATING THE OUTPUT COUPLING CAPACITOR The LM4981 features a low noise inverting charge pump that generates an internal negative supply voltage. This allows the outputs of the LM4981 to be biased about GND instead of a nominal DC voltage, like traditional headphone amplifi- ers. Because there component, the large DC blocking capacitors (typically 220µ ...
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... However, since the LM4981 is designed for headphone ap- plications, connecting a copper plane to the DAP’s PCB copper pad is not required. The DAP on the LM4981 should be connected to GND to ensure correct functionality. SELECTING PROPER EXTERNAL COMPONENTS Optimizing the LM4981’ ...
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Application Information Also, careful consideration must be taken in selecting a certain type of capacitor to be used in the system. Different www.national.com types of capacitors (tantalum, electrolytic, ceramic) have (Continued) unique performance characteristics and may affect overall system performance. ...
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... Application Information LM4981 DEMO BOARD ARTWORK (Continued) Top Layer Mid Layer 1 15 20147390 20147391 www.national.com ...
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Application Information www.national.com (Continued) Mid Layer 2 Bottom Layer 16 20147392 20147393 ...
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Revision History Rev 1.0 1.1 1.2 1.3 1.4 1.5 Date 8/29/05 Added the Typ Perf curves. 9/02/05 Added the Apps Information section and more Typ Perf curves. 9/06/05 Added the LLP Marking and the table. 9/23/05 Input some text edits ...
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... Deutsch Tel: +49 (0) 69 9508 6208 English www.national.com Français Tel: +33 ( 8790 Order Number LM4981SQ NS Package Number NSQAL016 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 ...