lm4651 National Semiconductor Corporation, lm4651 Datasheet
lm4651
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lm4651 Summary of contents
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... LM4651 & LM4652 Overture 170W Class D Audio Power Amplifier Solution General Description The IC combination of the LM4651 driver and the LM4652 power MOSFET provides a high efficiency, Class D sub- woofer amplifier solution. The LM4651 is a fully integrated conventional pulse width modulator driver IC. The IC contains short circuit, under voltage, over modulation, and thermal shut down protection circuitry ...
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... LM4652 (pins 2,6,10,11) Junction Temperature (Note 6) Soldering Information N, TA and TF Package (10 seconds) Storage Temperature System Electrical Characteristics for LM4651 and LM4652 The following specifications apply for +V specified. Typicals apply for T = 25˚C. For specific circuit values, refer to Figure 1 (Typical Audio Application Circuit). A ...
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... Note 2: All voltages are measured with respect to the GND pin unless otherwise specified. Note 3: For operating at case temperatures above 25˚C, the LM4651 must be de−rated based on a 150˚C maximum junction temperature and a thermal resistance ˚ ...
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Electrical Characteristics for LM4652 FIGURE 1. Typical Application Circuit and Test Circuit www.national.com (Notes (Continued) 4 DS101277-68 ...
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... LM4651 Pin Descriptions Pin No. Symbol 1 OUT The reference pin of the power MOSFET output to the gate drive circuitry. 1 2,27 BS ,BS The bootstrap pin provides extra bias to drive the upper gates High−Gate # 1 is the gate drive to a top side MOSFET in the H-Bridge. ...
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LM4652 Pin Descriptions Pin No. Symbol 1 GND − TSD ...
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External Components Description Components Supply de-coupling capacitors. See Supply Bypassing in the Application Information SBY1 SBY2 20. C section. SBY3 Provides a small DC voltage at the input to minimize the output DC offset seen by ...
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Typical Performance Characteristics THD+N vs. Output Power THD+N vs. Frequency vs. Bandwidth THD+N vs. Frequency vs. Bandwidth www.national.com (Continued) THD+N vs. Output Power DS101277-8 ...
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... Power Dissipation & Efficiency vs. Output Power Frequency Response Supply Current vs. Supply Voltage (LM4651 & LM4652) (Continued) Clipping Power Point & Efficiency vs. Switching Frequency (f DS101277-16 Supply Current vs. Switching Frequency (LM4651 & LM4652) DS101277-18 R vs. Temperature DS (ON) DS101277- DS101277-17 DS101277-20 DS101277-23 www.national.com ...
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... C START 10µF then the diagnostic circuitry will check approximately every second to see if an error condition has been corrected. If the error condition is no longer present, the LM4651/52 will return to normal operation. DS101277-1 Current Limiting and Short Circuit Protection: The resis- tor value connected between the SCKT pin and GND deter- mines the maximum output current ...
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... The pole of the filter is set by Equation (7). On-Board Regulators: The LM4651 has its own internal supply regulators for both analog and digital circuits. Sepa- ± ...
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... DC voltage to the input. This forces the duty cycle to 50% when there is no input signal. The result is a LM4651 and LM4652 system with near zero DC offset. The divider should be a 1.8M from the +6V output (pin 6) to the input (other side of 25k ...
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Application Information applications. In bridge operation, each output sees C This causes the extra factor the formula. The alterna- tive capacitor connected between each output, BYP V , and V , and ground. ...
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... Example Design of a Class D Amplifier The following is an example of how to design a class D amplifier system for a power subwoofer application utilizing the LM4651 and LM4652 to meet the design requirements listed below: • Output Power, 1% THD /R ). The power • ...
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... C is then placed as close as possible to the fl2 feedback inputs (pins 14, 19) of the LM4651 to filter off any noise picked up by the feedback traces. The combination lowers EMI and provides a cleaner audio feedback signal to the LM4651. R ...
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Application Information To account for the use of a mica washer simply subtract the thermal resistance of the mica washer from above. Recommendations for Critical External Components Circuit Suggested Symbol Value C 330pF fI1 C 100pF fI2 C 470pF f ...
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Application Information (Continued) FIGURE 8. Reference PCB top layer FIGURE 9. Reference PCB bottom layer 17 DS101277-26 DS101277-27 www.national.com ...
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Application Information FIGURE 11. Reference PCB bottom layer solder mask www.national.com (Continued) FIGURE 10. Reference PCB top layer solder mask 18 DS101277-28 DS101277-78 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number LM4651N NS Package Number N28B Order Number LM4652TF NS Package Number TF15B 19 www.national.com ...
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... NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...