LM4700 National Semiconductor, LM4700 Datasheet
LM4700
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LM4700 Summary of contents
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... Audio Power Amplifier with Mute and Standby Modes General Description The LM4700 is an audio power amplifier capable of deliver- ing typically 30W of continuous average output power into an 8 load with less than 0.1% (THD + N). The LM4700 has an independent smooth transition fade-in/ out mute and a power conserving standby mode which can be controlled by external logic ...
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... 150˚C 2˚C/W 43˚C/W 260˚C −40˚C T +150˚C A (Notes 4, 5) −20˚C T +85˚ (Note 1) 20V to 64V CC EE LM4700 Units (Limits) Typical Limit (Note 9) (Note 10 (min (max W/ch (min W/ch (min) 0. V/µ ...
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... LM4700 can deliver typically 22 Watts of continuous average power per channel with less than 0.1% (THD+N). ± With supplies above 20V, the LM4700 cannot deliver more than 22 watts into 4 due to current limiting of the output transistors. Thus, increasing the power supply ± above 20V will only increase the internal power dissipation, not the possible output power ...
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Test Circuit # 1 (Note 2) (DC Electrical Test Circuit) Test Circuit # 2 (Note 3) (AC Electrical Test Circuit) Bridged Amplifier Application Circuit FIGURE 2. Bridged Amplifier Application Circuit www.national.com DS012369-3 DS012369-4 DS012369-5 4 ...
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Single Supply Application Circuit FIGURE 3. Single Supply Amplifier Application Circuit Auxillary Amplifier Application Circuit FIGURE 4. Auxillary Amplifier Application Circuit DS012369-6 DS012369-7 5 www.national.com ...
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Equivalent Schematic (Excluding Active Protection Circuitry) www.national.com 6 DS012369-8 ...
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External Components Description Components 1 R Prevents currents from entering the amplifier’s non-inverting input which may be passed through to the B load upon power down of the system due to the low input impedance of the circuitry when the ...
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Typical Performance Characteristics THD + N vs Frequency DS012369-10 THD + N vs Output Power DS012369-13 THD + N vs Output Power DS012369-16 Clipping Voltage vs Supply Voltage DS012369-19 www.national.com THD + N vs Frequency DS012369-11 THD + N vs ...
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Typical Performance Characteristics Power Dissipation vs Output Power DS012369-22 Output Power vs Load Resistance DS012369-25 Pulse Response DS012369-28 (Continued) Power Dissipation vs Ouput Power DS012369-23 Output Power vs Supply Voltage DS012369-26 Large Signal Response DS012369-29 9 Power Dissipation vs Output ...
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Typical Performance Characteristics Power Supply Rejection Ratio DS012369-31 Safe Area DS012369-34 Pulse Thermal Resistance DS012369-37 www.national.com (Continued) Common-Mode Rejection Ratio DS012369-32 Spike Protection Response DS012369-35 Pulse Thermal Resistance DS012369-38 10 Open Loop Frequency Response DS012369-33 Supply Current vs Supply Voltage ...
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... Characteristics section for curves concerning Mute Attenu- ation vs Mute Pin Voltage. STANDBY MODE The standby mode of the LM4700 allows the user to drasti- cally reduce power consumption when the amplifier is idle. By placing a logic-high voltage on the standby pin, the ampli- fier will go into Standby Mode. In this mode, the current drawn from the V supply is typically less than 10 µ ...
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... SINGLE-SUPPLY AMPLIFIER APPLICATION The typical application of the LM4700 is a split supply ampli- fier. But as shown in Figure 3 , the LM4700 can also be used in a single power supply configuration. This involves using some external components to create a half-supply bias + ...
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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 LM4700. 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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... GBWP of 2.1 MHz is H less than the minimum GBWP of 5 MHz for the LM4700. This in will ensure that the high frequency response of the amplifier I will be no worse than 0.17 dB down at 20 kHz which is well within the bandwidth requirements of the design ...
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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. Isolated TO-220 11-Lead Package Order Number LM4700TF NS Package Number TF11B 2. A critical component is any component of a life ...