LM4732 National Semiconductor, LM4732 Datasheet
LM4732
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LM4732 Summary of contents
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... The LM4732 has a wide operating supply range from +/-10V - +/-40V allowing for lower cost unregulated power supplies to be used. The LM4732 amplifiers can easily be configured for bridge or parallel operation for 100W mono solutions. Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit © ...
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... Connection Diagrams www.national.com Plastic Package (Note 13) 200724D7 Top View Order Number LM4732TA See NS Package Number TA27A TO-220 Top Marking 200724D6 Top View U - Wafer Fab Code Z - Assemble Plant Code XY - Date Code TT - Die Run Traceability L4732TA - LM4732TA 2 ...
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... IHF-A-Weighting Filter 600Ω (Input Referred -40˚C to +150˚C (Notes 1, 2) ≤ T −20˚C ≤ MAX A 20V ≤ TOTAL = 8Ω unless otherwise specified. L LM4732 Typical Limit (Note 6) (Notes 110 0.02 0. 105 170 ...
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... Note 14: CCIR/ARM: A Practical Noise Measurement Method; by Ray Dolby, David Robinson and Kenneth Gundry, AES Preprint No. 1353 (F-3). www.national.com (Notes 1, 2) (Continued) -T )/θ or the number given in the Absolute Maximum Ratings, whichever is lower. For the LM4732 (case to sink) is increased, but the heat sink will be electrically isolated from θ ...
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Bridged Amplifier Application Circuit FIGURE 2. Bridged Amplifier Application Circuit 5 20072414 www.national.com ...
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Parallel Amplifier Application Circuit www.national.com FIGURE 3. Parallel Amplifier Application Circuit 6 20072413 ...
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Single Supply Application Circuit FIGURE 4. Single Supply Amplifier Application Circuit Note: * Optional components dependent upon specific design requirements. Auxiliary Amplifier Application Circuit FIGURE 5. Special Audio Amplifier Application Circuit 20072406 200724D5 7 www.national.com ...
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External Components Description (Figures 1-5) Components 1 R Prevents current from entering the amplifier’s non-inverting input. This current may pass through to the load B during system power down, because of the amplifier’s low input impedance when the undervoltage circuitry ...
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Optional External Component Interaction The optional external components have specific desired functions. Their values are chosen to reduce the bandwidth and eliminate unwanted high frequency oscillation. They may, however, cause certain undesirable effects when they interact. Interaction may occur when ...
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Typical Performance Characteristics THD+N vs Output Power/Channel ± 22V 4Ω, 80kHz BW L Output Power/Channel vs Supply Voltage f = 1kHz 4Ω, 80kHz BW L Total Power Dissipation vs Output Power/Channel 1% THD (max ...
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Typical Performance Characteristics Crosstalk vs Frequency ± 22V 10W OUT R = 4Ω, 80kHz BW L Mute Attenuation vs Mute Pin Current P = 10W/Channel OUT THD+N vs Frequency ± 22V & 50W OUT Bridge ...
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Typical Performance Characteristics THD+N vs Output Power ± 22V, Bridge Mode (Note 16 8Ω, 80kHz BW L Output Power vs Supply Voltage, Bridge Mode (Note 16 1kHz 8Ω, 80kHz BW L Note 16: Bridge ...
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... For a longer turn-on mute time, a larger time constant, τ (sec), is needed. For the values M1 M show above and with the MUTE pins tied together, the LM4732 will enter play mode when the voltage at point A is -17.6V. The voltage at point A is found with Equation (1) below. -t/τ ...
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... SINGLE-SUPPLY AMPLIFIER APPLICATION The typical application of the LM4732 is a split supply am- plifier. But as shown in Figure 4, the LM4732 can also be used in a single power supply configuration. This involves using some external components to create a half-supply bias which is used as the reference for the inputs and outputs. ...
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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 LM4732. In Figure 4, 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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... It is advisable to keep the output compensation components and the 0.1µF supply decoupling capacitors as close as possible to the LM4732 to reduce the effects of PCB trace resistance and inductance. For the same reason, the ground return paths should be as short as possible. ...
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... It is hard for most power amplifiers to drive highly capacitive loads very effectively and normally results in oscillations or ringing on the square wave response. If the output of the LM4732 is connected directly to a capacitor with no series resistance, the square wave response will exhibit ringing if the capacitance is greater than about 0.2µF. If highly capaci- ...
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Application Information www.national.com (Continued) FIGURE 6. Inverting Amplifier Application Circuit 18 20072421 ...
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Application Information (Continued) FIGURE 7. Reference PCB Schematic 19 200724F9 www.national.com ...
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... Application Information LM4732 REFERENCE BOARD ARTWORK Composite Layer Top Layer www.national.com (Continued) 200724F6 200724F5 20 200724F7 Silk Layer 200724F8 Bottom Layer ...
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... Monolithic Ceramic 20% Electrolytic Radial / 50V 20% Electrolytic Radial / 50V SPDT (on-on) Switch Non-Switched PC Mount RCA PCB Banana Jack - BLACK PCB Banana Jack - RED 27 lead TO-220 Power Socket with push lever release or 21 Comment 1/4 Watt 1/4 Watt 1/4 Watt 1/4 Watt 1/4 Watt 1/4 Watt 1/4 Watt Jack LM4732 IC www.national.com ...
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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) Non-Isolated TO-220 27-Lead Package Order Number LM4732TA NS Package Number TA27A 2. A critical component is any component of a life ...