LM4894 National Semiconductor, LM4894 Datasheet
LM4894
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LM4894 Summary of contents
Page 1
... Additionally, the LM4894 features an internal thermal shutdown protection mechanism. The LM4894 contains advanced pop & click circuitry which eliminates noises which would otherwise occur during turn-on and turn-off transitions. The LM4894 is unity-gain stable and can be configured by external gain-setting resistors. Key Specifications j Improved PSRR at 217Hz ...
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... Bump micro SMD Package Top View Order Number LM4894IBP See NS Package Number BPA09CDB Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit www.national.com (Continued) Order Number LM4894ITL, LM4894ITLX 20013736 See NS Package Number TLA09AAA 2 9 Bump micro SMD Package 20013794 Top View 20013701 ...
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... Limits apply for Conditions GND shutdown THD = 1% (max kHz LM4894LD 4Ω (Note 11) L LM4894 8Ω 0.4 Wrms 1kHz 200mV sine p-p ripple f = 217Hz (Note 1kHz (Note 9) ...
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... Note 8: For micro SMD only, shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase I Note 9: Unterminated input. Note 10: 10Ω terminated input. Note 11: When driving 4Ω loads from a 5V supply, the LM4894LD must be mounted to a circuit board. External Components Description (Figure 1) Components 1 ...
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... Typical Performance Characteristics LD Specific Characteristics LM4894LD THD+N vs Output Power V = 5V, 4Ω LM4894LD Power Dissipation vs Output Power THD+N vs Frequency V = 5V, 4Ω 20013790 Power Derating Curve 20013792 5 LM4894LD , and Power = 1W L 20013791 LM4894LD 20013793 www.national.com ...
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Typical Performance Characteristics Non-LD Specific Characteristics THD+N vs Frequency 5V, 8Ω and PWR = 400mW DD L THD+N vs Frequency 3V, 4Ω and PWR = 225mW DD L THD+N vs ...
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Typical Performance Characteristics Non-LD Specific Characteristics THD+N vs Output Power @ V = 3V, 8Ω THD+N vs Output Power @ V = 2.6V, 8Ω Power Supply Rejection Ratio (PSRR) Input 10Ω Terminated (Continued) L 20013743 L ...
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Typical Performance Characteristics Non-LD Specific Characteristics Power Supply Rejection Ratio (PSRR) Input 10Ω Terminated Output Power vs Supply Voltage Power Dissipation vs Output Power www.national.com (Continued Power Supply Rejection Ratio (PSRR) DD 20013749 20013751 Power Dissipation ...
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Typical Performance Characteristics Non-LD Specific Characteristics Power Dissipation vs Output Power Supply Current vs Shutdown Voltage Shutdown Low Clipping (Dropout) Voltage vs Supply Voltage (Continued) 20013755 Supply Current vs Shutdown Voltage 20013769 Open Loop Frequency Response 20013774 9 Output Power ...
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Typical Performance Characteristics Non-LD Specific Characteristics Power Derating Curve Input CMRR vs Frequency www.national.com (Continued) 20013776 20013778 10 Noise Floor 20013777 Input CMRR vs Frequency 20013779 ...
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... In most applications, this would require input signals that are 180˚ out of phase with each other. The LM4894 can be used, however single ended input amplifier while still retaining its fully differential benefits. In fact, completely unrelated signals may be placed /2 ...
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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 LM4894 should be 2 5in (min) for the same supply voltage and load resistance. ...
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... The LM4894 is unity-gain stable, giving the designer maxi- mum system flexibility. The LM4894 should be used in low closed-loop gain configurations to minimize THD+N values and maximize signal to noise ratio. Low gain configurations require large input signals to obtain a given output power. ...
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... The high frequency pole is determined by the product of the desired frequency pole, f With 150kHz which is much smaller than the LM4894 GBWP of 10MHz. This figure displays that if a designer has a need to design an amplifier with a higher differential gain, the LM4894 can still be used without running into bandwidth ...
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Application Information FIGURE 2. Single-Ended Input, "Shutdown-Low" Configuration FIGURE 3. Single-Ended Input, "Shutdown-High" Configuration (Continued) 15 20013787 20013785 www.national.com ...
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... Physical Dimensions X1 = 1.336 www.national.com inches (millimeters) unless otherwise noted 9-Bump micro SMD Order Number LM4894IBP NS Package Number BPA09CDB ± ± 0. 1.361 0. 0.850 16 ± 0.10 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) LLP Order Number LM4894LD NSPackage Number LDA10B 17 www.national.com ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted (Continued) Mini Small Outline (MSOP) Order Number LM4894MM NSPackage Number MUB10A 18 ...
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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 (Continued) 9-Bump micro SMD Order Number LM4894ITL, LM4894ITLX NS Package Number TLA09AAA ± ...