LM4850 National Semiconductor, LM4850 Datasheet
LM4850
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LM4850 Summary of contents
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... The unity-gain stable LM4850’s gain is set by external gain-setting resistors Note 1: An LM4850LD that has been properly mounted to a circuit board will deliver 1.9W into 3Ω (at 1% THD+N). The other package options for the LM4850 will deliver 1.1W into 8Ω (at 1% THD+N). See Application Infor- mation sections for further information concerning the LM4850LD, LM4850MM, and LM4850MT ...
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... Connection Diagrams www.national.com 20001051 Top View 10 Lead MSOP Order Number LM4850MM See NS Package Number MUB10A Top View 14 Lead TSSOP Order Number LM4850MT See NS Package Number MTC14 Top View 14 Lead LLP Order Number LM4850LD See NS Package Number LDA14A 2 20001052 20001002 ...
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... BTL Mode BTL OUT+ to BTL OUT− LM4850LD; BTL Mode 3Ω L THD (Note 11) LM4850LD; BTL Mode 4Ω L THD (Note 11) LM4850MT, MM; BTL Mode THD BTL Mode 8Ω L THD Mode 8Ω L THD Mode 32Ω ...
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... Note 10: The given θ is for a LM4850LD with the Exposed-DAP soldered to an exposed 1in JA Note 11: When driving 3Ω or 4Ω loads from a 5V supply, the LM4850 must be mounted to a circuit board. Note 12: Limits are guaranteed to National’s AOQL ( Average Outgoing Quality Level ). External Components Description (Refer to Figure 1 ...
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... LD Specific Characteristics LM4850LD THD+N vs Frequency LM4850LD THD+N vs Output Power (Continued) Functional Description 1/(2π Refer to the section, Proper Selection of External Components 1/(2π 20001075 20001077 LM4850LD THD+N vs Frequency 20001076 LM4850LD THD+N vs Output Power 20001078 www.national.com ...
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... Power Dissipation vs Output Power Note 13: This curve shows the LM4850LD’s thermal dissipation ability at different ambient temperatures given the exposed-DAP of the part is soldered to a plane of 1oz. Cu with an area given in the label of each curve. This label also designated whether the plane exists on the same (top) layer as the chip, on the bottom layer both layers ...
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Typical Performance Characteristics Non-LD Specific Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Output Power (Continued) THD+N vs Frequency 20001067 THD+N vs Output Power 20001039 THD+N vs Output Power 20001041 7 20001068 20001040 20001042 www.national.com ...
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Typical Performance Characteristics Non-LD Specific Characteristics THD+N vs Output Power THD+N vs Output Power THD+N vs Output Power www.national.com (Continued) THD+N vs Output Power 20001043 THD+N vs Output Power 20001045 Output Power vs Load Resistance 20001047 8 20001044 20001046 20001048 ...
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Typical Performance Characteristics Non-LD Specific Characteristics Output Power vs Load Resistance Output Power vs Supply Voltage Power Dissipation vs Output Power (Continued) Output Power vs Supply Voltage 20001049 Dropout Voltage vs Supply Voltage 20001071 Power Dissipation vs Output Power 20001055 ...
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Typical Performance Characteristics Non-LD Specific Characteristics Power Derating Curve Noise Floor Supply Current vs Supply Voltage www.national.com (Continued) 20001057 Open Loop Frequency Response 20001059 Power Supply Rejection Ratio 20001061 10 Channel Separation 20001080 20001062 20001060 ...
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... Package Engineering Group under application note AN1187. V BRIDGE CONFIGURATION EXPLANATION When the LM4850 is in BTL mode, the output of amplifier A1 serves as the input to amplifier A2, which results in both amplifiers producing signals identical in magnitude, but out of phase by 180˚. Consequently, the differential gain for the ...
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... This also interrupts the voltage divider set up by the resistors R HP-IN pin, switching the LM4850 out of BTL mode and into SE mode. The amplifier then drives the headphones, whose impedance is in parallel with resistors R ...
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... PROPER SELECTION OF EXTERNAL COMPONENTS Proper selection of external components in applications us- ing integrated power amplifiers is critical for optimum device and system performance. While the LM4850 is tolerant to a variety of external component combinations, consideration must be given to the external component values that maxi- mize overall system quality. ...
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... A . With and f = 100kHz, the resulting GBWP = 150kHz which is much smaller than the LM4850 GBWP of 10MHz. This difference indicates that a designer can still use the LM4850 at higher differential gains without bandwidth limitations. www.national.com PCB LAYOUT AND SUPPLY REGULATION (Continued) CONSIDERATIONS FOR DRIVING 3Ω AND 4Ω LOADS Power dissipated by a load is a function of the voltage swing across the load and the load’ ...
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Demonstration Board Layout Recommended LD PC Board Layout: Component-Side SilkScreen FIGURE 3. Recommended LD PC Board Layout: Component-Side Layout FIGURE 4. 15 20001081 20001082 www.national.com ...
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Demonstration Board Layout www.national.com (Continued) Recommended LD PC Board Layout: Bottom-Side Layout FIGURE 5. Recommended MM PC Board Layout: Component-Side SilkScreen FIGURE 6. 16 20001083 20001093 ...
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Demonstration Board Layout (Continued) Recommended MM PC Board Layout: Component-Side Layout FIGURE 7. Recommended MM PC Board Layout: Bottom-Side Layout FIGURE 8. 17 20001091 20001092 www.national.com ...
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... Physical Dimensions 14-Lead MOLDED PKG, TSSOP, JEDEC, 4.4mm BODY WIDTH www.national.com inches (millimeters) unless otherwise noted Order Number LM4850MT NS Package Number MTC14 18 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 10-Lead Mini SOIC, 118 Mil Wide, .5MM Pitch PKG Order Number LM4850MM NS Package Number MUB10A 19 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) unless otherwise noted (Continued) 14-Lead LLP, 118 Mil Wide, .8MM Pitch PKG Order Number LM4850LD NS Package Number LDA14A 2. A critical component is any component of a life ...