LM4856 National Semiconductor, LM4856 Datasheet
LM4856
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LM4856 Summary of contents
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... It delivers high quality output power from a surface-mount package and requires only eight external components. The industry leading micro SMD package only utilizes 2mm x 2.3mm of PCB space, making the LM4856 the most space efficient audio sub system available today. Typical Application Boomer ® ...
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... SMD Marking (ITL) 200607E4 Top View X - Date Code T - Die Traceability G - Boomer Family B7 - LM4856ITL 18 Lead LLP Marking 20060701 Top View NS - Std NS Logo U - Wafer Fab Code Z - Assembly Plant Code Digit Date Code TT - Die Run Traceability L4856LQ - LM4856LQ Datasheet pdf - http://www.DataSheet4U.net/ ...
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... Output modes 0V; No loads IN Output modes 0V; Loaded (Figure 1) IN Output mode SPKR ; R = 4Ω OUT L THD 1kHz, LM4856LQ SPKR ; R = 8Ω OUT L THD 1kHz R and 32Ω OUT OUT L THD+N = 0.5 1kHz SPKR OUT ...
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... Input referred minimum gain Input referred maximum gain BTL gain from Phone_In _IHF to SPKR OUT Output Mode Maximum gain setting Mininum gain setting Maximum gain setting Mininum gain setting 4 LM4856 Units (Limits) Typical Limits (Note 5) (Notes 6, 11) 0.4 V (max) GND V (min) -34 ...
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... Output modes 0V; No loads IN Output modes 0V; Loaded (Figure 1) IN Output mode SPKR ; R = 4Ω OUT L THD 1kHz, LM4856LQ SPKR ; R = 8Ω OUT L THD 1kHz R and 32Ω OUT OUT L THD+N = 0.5 1kHz SPKR OUT ...
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... Input referred maximum gain BTL gain from Phone_In _IHF to SPKR OUT Output Mode Maximum gain setting Mininum gain setting Maximum gain setting Mininum gain setting are for an LM4856 mounted on a demonstration board with a 4in JC 6 LM4856 Units (Limits) Typical Limits (Note 5) ...
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... This is the BYPASS pin capacitor. It filters the V B Typical Performance Characteristics THD+N vs Frequency LM4856LQ THD+N vs Frequency Functional Description also creates a highpass filter with the internal resistor voltage and helps maintain the LM4856’s PSRR. DD 200607F0 200607B1 7 (Input Impedance pin and helps maintain ...
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Typical Performance Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency www.national.com (Continued) THD+N vs Frequency 200607G7 THD+N vs Frequency 200607B5 THD+N vs Frequency 200607H0 8 200607G8 200607G9 200607H1 Datasheet pdf - http://www.DataSheet4U.net/ ...
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... Typical Performance Characteristics THD+N vs Output Power LM4856LQ THD+N vs Output Power THD+N vs Output Power (Continued) THD+N vs Output Power 200607F2 THD+N vs Output Power 200607B9 THD+N vs Output Power 200607C1 9 LM4856LQ 200607F3 200607H2 200607H3 www.national.com Datasheet pdf - http://www.DataSheet4U.net/ ...
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Typical Performance Characteristics Power Supply Rejection Ratio Power Supply Rejection Ratio Power Supply Rejection Ratio www.national.com (Continued) Power Supply Rejection Ratio 200607C3 Power Supply Rejection Ratio 200607C5 Power Supply Rejection Ratio 200607C7 10 200607H4 200607H5 200607H6 Datasheet pdf - ...
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Typical Performance Characteristics Output Power vs Supply Voltage Output Power vs Load Resistance Power Dissipation vs Output Power (Continued) Output Power vs Supply Voltage 200607D7 Output Power vs Load Resistance 200607D9 Power Dissipation vs Output Power 200607E1 11 200607H7 ...
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Typical Performance Characteristics Supply Current vs Supply Voltage Frequency Response www.national.com (Continued) Channel Separation 200607C9 Frequency Response 200607D4 Frequency Response 200607I1 12 200607I2 200607I0 Datasheet pdf - http://www.DataSheet4U.net/ ...
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Typical Performance Characteristics (Continued) Output Noise vs Output Mode (V DD Output Mode SPKROUT LOUT/ROUT Output Noise Output Noise (µV) (µ (G1 = 0dB) 18 (G1 = 6dB (G1 = ...
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... After the data byte is sent, the master must generate another 2 C interface acknowledge to see if the LM4856 received the data. If the master has more data bytes to send to the LM4856, then the master can repeat the previous two steps until all data bytes have been sent shown in Figure 2. The data The “ ...
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Application Information BIT D7 Function Name V4 Default Handsfree Speaker Output 12dB MUTE 12dB MUTE ...
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... THD+N. This high power is achieved through careful consideration of necessary thermal design. Failing to opti- mize thermal design may compromise the LM4856’s high power performance and activate unwanted, though neces- sary, thermal shutdown protection. ...
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... BRIDGE CONFIGURATION EXPLANATION As shown in Figure 1, the LM4856 consists of three pairs of output amplifier blocks (A4-A6). Amplifier block A6 consists of a bridged-tied amplifier pair that drives SPKROUT. The LM4856 drives a load, such as a speaker, connected be- tween outputs, SPKROUT+ and SPKROUT- ...
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... As an example when using a speaker with a low frequency limit of 150Hz using Equation (9) is 0.063µF. The 0.22µ shown in Figure 1 allows the LM4856 to drive high effi- i ciency, full range speaker whose response extends below 40Hz. Bypass Capacitor Value Selection Besides minimizing the input capacitor size, careful consid- ...
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Demonstration ITL/LQ Board Layout Recommended ITL PC Board Layout: Top Overlay Layer Recommended ITL PC Board Layout: Middle 1 Layer 200607G0 Recommended ITL PC Board Layout: Top Layer 200607F7 Recommended ITL PC Board Layout: Middle 2 Layer 19 200607F9 ...
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Demonstration ITL/LQ Board Layout Recommended ITL PC Board Layout: Recommended LQ PC Board Layout: www.national.com (Continued) 200607F6 Bottom Layer 200607G4 Top Layer 20 200607G5 Recommended LQ PC Board Layout: Top Overlay Layer 200607G2 Recommended LQ PC Board Layout: Middle ...
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Demonstration ITL/LQ Board Layout Recommended LQ PC Board Layout: Middle 2 Layer (Continued) 200607G3 Recommended LQ PC Board Layout: Bottom Layer 21 200607G1 www.national.com Datasheet pdf - http://www.DataSheet4U.net/ ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 24-Lead MOLDED PKG, Leadless Leadframe Package LLP Order Number LM4856LQ NS Package Number LQA24A 22 Datasheet pdf - http://www.DataSheet4U.net/ ...
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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) 18-Bump micro SMD Order Number LM4856ITL NS Package Number TLA18AAA ...