LM4849 National Semiconductor, LM4849 Datasheet
LM4849
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LM4849 Summary of contents
Page 1
... Note 1: When properly mounted to the circuit board, the LM4849MH will deliver 2W into 4Ω. See the Application Information section for LM4849MH usage information. Note 2: An LM4849MH that has been properly mounted to the circuit board and forced-air cooled will deliver 2.2W into 3Ω. Connection Diagram ...
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... LM4849 Typical Limit (Note 14) (Note 15) 2.7 5 0.7 2.0 0.8 x VDD V (min) 0.2 x VDD V (max) LM4849 Typical Limit (Note 14) (Note 15) ± 0.75 -75 -78 -78 LM4849 Typical Limit (Note 14) (Note 15) = 32Ω 32Ω 0.065 58 102 65 41˚C/W 54˚C/W 59˚C/W 93˚C/W ≤ 5.5V Units (Limits) V (min) V (max) mA (max) µ ...
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... Note 7: All voltages are measured with respect to the ground pins, unless otherwise specified. All specifications are tested using the typical application as shown in Figure 2. Note 8: When driving 3Ω loads from a 5V supply the LM4849MH exposed DAP must be soldered to the circuit board and forced-air cooled. Note 9: When driving 4Ω loads from a 5V supply the LM4849MH exposed DAP must be soldered to the circuit board. ...
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www.national.com 4 ...
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... Left In 1, Right Left In 1, Right Left In 2, Right Left In 2, Right 20076770 20076772 5 Bridged Output Single-Ended Output Vol. Adjustable - Muted Vol. Adjustable Vol. Adjustable - Muted Vol. Adjustable Muted Muted LM4849MH THD+N vs Frequency 20076771 LM4849MH THD+N vs Frequency 20076773 www.national.com ...
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Typical Performance Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency www.national.com (Continued) THD+N vs Frequency 20076757 THD+N vs Frequency 20076714 THD+N vs Frequency 20076716 6 20076758 20076715 20076717 ...
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Typical Performance Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency (Continued) 20076718 20076720 THD+N vs Output Power 20076722 7 THD+N vs Frequency 20076719 THD+N vs Frequency 20076721 20076724 www.national.com ...
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Typical Performance Characteristics THD+N vs Output Power THD+N vs Output Power THD+N vs Output Power www.national.com (Continued) THD+N vs Output Power 20076725 THD+N vs Output Power 20076727 THD+N vs Output Power 20076729 8 20076726 20076728 20076730 ...
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Typical Performance Characteristics THD+N vs Output Power THD+N vs Output Power THD+N vs Output Voltage Line Out Pins (Continued) THD+N vs Output Power 20076731 THD+N vs Output Power 20076733 THD+N vs Output Voltage 20076759 9 20076732 20076734 Line Out Pins ...
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Typical Performance Characteristics Output Power vs Load Resistance Output Power vs Load Resistance Dropout Voltage www.national.com (Continued) 20076762 20076707 20076753 10 Output Power vs Load Resistance 20076706 Power Supply Rejection Ratio 20076735 Output Power vs Load Resistance 20076708 ...
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Typical Performance Characteristics Noise Floor Volume Control Characteristics Power Dissipation vs Output Power (Continued) 20076741 20076736 20076752 11 Noise Floor 20076742 Power Dissipation vs Output Power 20076751 Power Derating Curve 20076763 www.national.com ...
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... Typical Performance Characteristics Crosstalk Output Power vs Supply Voltage LM4849MH Power Dissipation vs Output Power Note 17: These curves show the thermal dissipation ability of the LM4849MH at different ambient temperatures given these conditions: 2 500LFPM + 2in : The part is soldered to a 2in 2 2in on bottom: The part is soldered to a 2in ...
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... If the heatsink and amplifier share the same PCB layer, a nominal 2.5in necessary for 5V operation with a 4Ω load. Heatsink areas not placed on the same PCB layer as the LM4849 should be 2 5in (min) for the same supply voltage and load resistance. ...
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... Besides affecting system cost and size, the input coupling capacitor has an effect on the LM4849’s click and pop per- formance. When the supply voltage is first applied, a tran- sient (pop) is created as the charge on the input capacitor changes from zero to a quiescent state. The magnitude of the pop is directly proportional to the input capacitor’ ...
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... As an example when using a speaker with a low frequency limit of 150Hz, the input coupling capacitor using Equation (7), is 0.063µF. The 0.33µF input coupling capacitor shown in Figure 1 allows the LM4849 to drive high efficiency, full range speaker whose response extends below 30Hz. OPTIMIZING CLICK AND POP REDUCTION ...
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... The LM4849 has an internal stereo volume control whose setting is a function of the DC voltage applied to the DC VOL CONTROL pin. The LM4849 volume control consists of 31 steps that are individually selected by a variable DC voltage level on the volume control pin. The range of the steps, controlled by the DC voltage, are from 0dB - 78dB ...
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... The Output Power vs Supply Voltage graph for an 8Ω load indicates a minimum supply voltage of 4.6V. This is easily met by the commonly used 5V supply voltage. The additional voltage creates the benefit of headroom, allowing the LM4849 to produce peak output power in excess of 1W without clipping or other audible distortion. The choice of 17 Voltage Range (Vdd = 3) ...
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... After satisfying the LM4849’s power dissipation require- ments, the minimum differential gain needed to achieve 1W dissipation in an 8Ω load is found using Equation (13). Thus, a minimum overall gain of 2.83 allows the LM4849’s to reach full output swing and maintain low noise and THD+N performance. ...
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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 LM4849MH 2. A critical component is any component of a life support device or system whose failure to perform ...