LM4854 National Semiconductor, LM4854 Datasheet
LM4854
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LM4854 Summary of contents
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... The LM4854 is available in the very space-efficient 12-lead micro SMD, exposed-DAP LLP for higher power applica- tions, and TSSOP packages. Note 1: An LM4854LD that has been properly mounted to a circuit board will deliver 1.7W (typ) into a 4Ω load. Key Specifications j LLP BTL output power (R = 3.2Ω ...
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Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit (Pin out shown for the 12-pin large bump micro SMD IBL package. Consult the "Connection Diagrams" for the LLP or MT package pin out.) www.national.com 2 20038201 ...
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... Connection Diagrams LM4854IBL Pin Designation 20038202 Top View (Bump-side down) Order Number LM4854IBL See NS Package Number BLA12BAB Micro SMD Marking 20038203 Top View X - Date Code T - Die Traceability G - Boomer Family 54 - LM4854IBL Pin (Bump) Number Pin Function A1 L-IN B1 GND C1 R-IN D1 MONO-IN A2 L-OUT B2 BYPASS ...
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... Connection Diagrams Top View Order Number LM4854LD See NS Package Number LDA14A Top View Order Number LM4854MT See NS Package Number MTC14 www.national.com 20038204 Bottom Line - Part Number 20038205 Bottom 2 lines - Part Number 4 200382A5 Top View U - Fab Code Z - Plant Code XY - Date Code TT - Die Tracebility ...
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... 217Hz 1kHz 1.0µF BYPASS 5 121˚C/W 42˚C/W (Note 7) 109˚C/W (Note 3) ≤ T −40˚C ≤ MAX A 2.4V ≤ 5V 25˚C. A LM4854 Typical Limit (Note 8) (Notes 9, 10) 5 0.05 0.2 2 200 0.1 1.0 1.4 0.4 www.national.com 220˚C 3˚C/W 40˚ ...
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... Quiescent Power Supply Current DD I Standby Quiescent Power Supply STBY Current I Shutdown Current SD V Output Offset Voltage OS www.national.com = 25˚C. A Conditions THD = 1% (max 1kHz (Note12 3.2Ω (LM4854LD 4Ω (LM4854LD 8Ω L THD = 10% (max 1kHz (Note12 3.2Ω (LM4854LD 4Ω (LM4854LD 8Ω L 20Hz ≤ ...
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... THD = 10% (max 1kHz (Note11 4Ω (LM4854LD 8Ω L 20Hz ≤ f ≤ 20kHz 4Ω 800mW (LM4854LD 8Ω 150mW 1kHz 4Ω 500mW (LM4854LD 8Ω 150mW 1kHz 1.0µF IN BYPASS P = 900mW 8Ω 3.0V) (Continued 25˚C. A LM4854 ...
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... Note 10: Datasheet minimum and maximum specification limits are guaranteed by design, test, or statistical analysis. Note 11: Output power is measured at the amplifier’s package pins. Note 12: When driving 4Ω loads and operating supply, the LM4854LD must be mounted to a circuit board that has a minimum of 2.5in2 of exposed, uninterrupted copper area connected to the LLP package’s exposed DAP. ...
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... Refer to the Application Information section sets the closed-loop gain. i 200382D8 200382C0 1/2π and R create ’s value. i THD+N vs Frequency 200382D9 LM4854LD 4Ω (BTL 400mW OUT THD+N vs Frequency 200382B8 16Ω (SE 50mW OUT www.national.com and ...
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... THD+N vs Frequency 32Ω (SE 50mW OUT THD+N vs Frequency 8Ω (BTL 150mW OUT www.national.com (Continued) THD+N vs Frequency 200382B9 THD+N vs Frequency 200382B7 200382E0 LM4854LD = 4Ω (BTL 150mW OUT 200382B5 = 16Ω (SE 30mW OUT ...
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... THD+N vs Output Power 200382B6 (from top to bottom at 200mW) 20kHZ, 20Hz, 1kHz THD+N vs Output Power 200382C6 (from top to bottom at 30mW) 20kHz, 20Hz, 1kHz 11 200382E1 LM4854LD = 5V 4Ω (BTL), L 200382C4 = 5V 16Ω (SE), L www.national.com ...
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... THD+N vs Output Power 200382C5 (from top to bottom at 200mW) 20kHz, 20Hz, 1kHz THD+N vs Output Power 200382C3 (from top to bottom at 20mW) 20kHz, 20Hz, 1kHz 12 200382E2 LM4854LD = 3V 4Ω (BTL), L 200382C1 = 3V 16Ω (SE), L ...
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... (from top to bottom at 4V): 10% THD+N, 1% THD+N (Continued) vs Power Supply Voltage 200382C2 R = 8Ω (BTL (from top to bottom at 4V) 10% THD+N, 1% THD+N PSRR vs Frequency 200382A7 Output Power 200382A8 = 1kHz, IN 200382E3 LM4854LD = 5V 4Ω (BTL 10Ω SOURCE www.national.com ...
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... 10Ω SOURCE PSRR vs Frequency 32Ω (SE 10Ω SOURCE www.national.com (Continued) PSRR vs Frequency 200382B4 PSRR vs Frequency 200382B3 200382B2 = 16Ω (SE 10Ω SOURCE 200382E4 LM4854LD = 4Ω (BTL 10Ω SOURCE ...
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... 10Ω SOURCE PSRR vs Frequency 32Ω (SE 10Ω SOURCE (Continued) PSRR vs Frequency 200382B1 V DD Amplifier Power Dissipation vs Load Power Dissipation 200382B0 LM4854IBL/MT 8Ω (BTL 200382A9 = 3V 16Ω (SE 10Ω SOURCE 200382D1 = 5V 1kHz IN www.national.com ...
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... IN 200382E9 = 5V, = 1kHz, 16 Amplifier Power Dissipation vs Load Power Dissipation 200382C8 LM4854IBL/MT 3V 8Ω (BTL 1kHz L IN Power Dissipation Derating Curve 200382E6 LM4854IBL 5V 8Ω (BTL 1kHz L IN ...
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... Amplifier Power Dissipation vs Load Power Dissipation 200382E7 LM4854IBL/MT, V (from top to bottom at 0.02W 16Ω (SE both channels driven and loaded vs Load Resistance 200382D2 LM4854IBL/MT, SE Load (both channels driven and f = 1kHz, (from top to bottom at 12Ω): ...
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... The signal returns to circuit ground through the headphone jack’s sleeve. The LM4854 eliminates these coupling capacitors. When the LM4854 is configured to drive SE loads, AMP2 is internally configured to apply stereo headphone jack’s DD sleeve ...
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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 LM4854 should be 2 5in (min) for the same supply voltage and load resistance. ...
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... In mono mode, external resistors R fL loop gain of AMP1, whereas two internal 20kΩ resistors set AMP2’s gain at -1. The LM4854 drives a load, such as a speaker, connected between the two amplifier outputs, L-OUT and BTL-OUT. Figure 2 shows that AMP1’s output serves as AMP2’s input. ...
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... Fast turn-on is assured be- cause all bias points remain at the same voltage as when the part is in fully active operation. The LM4854 returns to fully active operation in 100µs (typ) after the input voltage on the STANDBY pin switches from a logic low to a logic high. ...
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... Equation (7 example when using a speaker with a low frequency limit of 150Hz shown in Figure 2 allows the LM4854 to drive high effi- i ciency, full range speaker whose response extends below 30Hz. Bypass Capacitor Value Selection Besides minimizing the input capacitor size, careful consid- eration should be paid to value of CB, the capacitor con- nected to the BYPASS pin ...
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... Power Dissipation section. After satisfying the LM4854’s power dissipation requirements, the minimum differential gain needed to achieve 1W dissipation in an 8Ω load is found using Equation (10). Thus, a minimum gain of 2.83 allows the LM4854’s to reach T (ms) ON full output swing and maintain low noise and THD+N perfor- 120 mance. For this example, let AVD = 3. The amplifier’ ...
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... AVD, determines the upper passband response limit. With AVD = 3 and fH = 100kHz, the closed-loop gain bandwidth product (GBWP) is 300kHz. This is less than the LM4854’s 3.5MHz GBWP. With this margin, the amplifier can be used in designs that require more differential gain while avoiding performance restricting bandwidth limitations ...
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Demonstration Board Layout (Continued) FIGURE 9. Recommended MM PC Board Layout: Bottom_Side Layout FIGURE 10. Recommended MT PC Board Layout: Component-Side SilkScreen FIGURE 11. Recommended MT PC Board Layout: Component-Side Layout FIGURE 12. Recommended MT PC Board Layout: Bottom-Side Layout ...
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Demonstration Board Layout www.national.com (Continued) FIGURE 15. Recommended LD PC Board Layout: Upper Inner-Layer Layout FIGURE 16. Recommended LD PC Board Layout: Lower Inner-Layer Layout FIGURE 17. Recommended LD PC Board Layout: Bottom-Side Layout 26 20038231 20038232 20038233 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted TSSOP Package Order Number LM4854MT NS Package Number MTC14 27 www.national.com ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted (Continued) 14-Lead LLP Package Order Number LM4854LD NS Package Number LDA14A 28 ...
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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) 12-Bump micro SMD Package Order Number LM4854IBL, LM4854IBLX NS Package Number BLA12BAB ± ...