LM4731 National Semiconductor, LM4731 Datasheet
LM4731
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LM4731 Summary of contents
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... The LM4731 also has a under voltage lock out feature for click and pop free power off and on. The LM4731 has a wide operating supply range from +/-10V - +/-28V allowing for lower cost unregulated power supplies to be used. ...
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Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit www.national.com 2 20060353 ...
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... IHF — A-Weighting Filter R = 600Ω (Input Referred) IN Not in Standby Mode (Play) In Standby Mode 3 −40˚C to +150˚C (Notes 1, 2) ≤ T −20˚C ≤ MAX A 20V ≤ TOTAL LM4731 (Limits) Typical Limit (Note 6) (Notes 0.03 0.5 % (max) ...
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... Without feedback compensation the slew rate is typically larger. Note 12: The LM4731TA package TA15A is a non-isolated package setting the tab of the device and the heat sink to V-potential when the LM4731TA is directly mounted to the heat sink using only thermal compound mica washer is used in addition to thermal compound, θ ...
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Single Supply Application Circuit FIGURE 3. Single Supply Amplifier Application Circuit Note: * Optional components dependent upon specific design requirements. Auxiliary Amplifier Application Circuit FIGURE 4. Special Audio Amplifier Application Circuit 20060306 20060307 5 www.national.com ...
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External Components Description ( See Figures Components 1 R Prevents currents from entering the amplifier’s non-inverting input which may be passed through to the load B upon power down of the system due to the low ...
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Typical Performance Characteristics Supply Current vs Supply Voltage THD+N vs Frequency ± 18V 1W/Channel 4Ω, 80kHz BW L THD+N vs Output Power ± 18V 4Ω, 80kHz BW L ± 20060368 THD+N vs Frequency ...
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Typical Performance Characteristics Output Power vs Supply Voltage f = 1kHz 4Ω, 80kHz BW L Power Dissipation vs Output Power 1% THD (max 4Ω, 80kHz BW L Crosstalk vs Frequency ± 18V 10W, O ...
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Typical Performance Characteristics Mute Attenuation vs Mute Pin Voltage ± 22V 1W 8Ω, 80kHz BW L Supply Current vs Standby Pin Voltage ± 22V (Continued) Standby Attenuation vs 20060360 20060367 9 Standby Pin Voltage ± ...
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... Since convection CS heat flow (power dissipation) is analogous to current flow, thermal resistance is analogous to electrical resistance, and temperature drops are analogous to voltage drops, the power dissipation out of the LM4731 is equal to the following DMAX JMAX where T = 150˚C, T ...
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... Thus, to use these devices to control the logic circuitry of the LM4731, a “level shifter,” like the one shown in Figure 5, must be employed. A level shifter is not needed in a split-supply configuration since ground is also half-supply. ...
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... To achieve a transient free power-up and power-down, the voltage seen at the input terminals should be ideally the same. Such a signal will be common-mode in nature, and will be rejected by the LM4731. In Figure 3, the resistor R serves to keep the inputs at the same potential by limiting the voltage difference possible between the two nodes. This should significantly reduce any type of turn-on pop, due to an uneven charging of the amplifier inputs ...
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Application Information (Continued) FIGURE 6. Reference PCB Schematic 13 20060355 www.national.com ...
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... Application Information LM4731 REFERENCE BOARD ARTWORK Composite View Top Layer www.national.com (Continued) 20060356 20060358 14 Silk Screen 20060357 Bottom Layer 20060359 ...
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Application Information Symbol Value 47kΩ IN1 IN2 1kΩ 20kΩ 1kΩ 4.7Ω SN1 SN2 R 2.7Ω ...
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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 Non-Isolated TO-220 15-Lead Package Order Number LM4731TA NS Package Number TA15A 2. A critical component is any component of a life ...