LM4937RL/NOPB National Semiconductor, LM4937RL/NOPB Datasheet

IC AUDIO SUBSYSTM 1.25W 36USMDXT

LM4937RL/NOPB

Manufacturer Part Number
LM4937RL/NOPB
Description
IC AUDIO SUBSYSTM 1.25W 36USMDXT
Manufacturer
National Semiconductor
Series
Boomer®r
Type
Class ABr
Datasheet

Specifications of LM4937RL/NOPB

Output Type
1-Channel (Mono) with Mono and Stereo Headphones
Max Output Power X Channels @ Load
1.25W x 1 @ 8 Ohm; 80mW x 2 @ 32 Ohm
Voltage - Supply
2.7 V ~ 5.5 V
Features
Depop, Differential Inputs, I²C, I²S, Mute, Shutdown, SPI, Volume Control
Mounting Type
Surface Mount
Package / Case
36-MicroSMDxt
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
LM4937RLTR
© 2007 National Semiconductor Corporation
LM4937
Audio Sub-System with OCL Stereo Headphone Output
and RF Suppression
General Description
The LM4937 is an integrated audio sub-system designed for
mono voice, stereo music cell phones connecting to base
band processors with mono differential analog voice paths.
Operating on a 3.3V supply, it combines a mono speaker am-
plifier delivering 520mW into an 8Ω load, a stereo headphone
amplifier delivering 36mW per channel into a 32Ω load, and
a mono earpiece amplifier delivering 55mW into a 32Ω load.
It integrates the audio amplifiers, volume control, mixer, and
power management control all into a single package. In ad-
dition, the LM4937 routes and mixes the single-ended stereo
and differential mono inputs into multiple distinct output
modes. The LM4937 features an I
range audio and an I
The full range music path features an SNR of 85dB with a
192kHz playback.
Boomer audio power amplifiers are designed specifically to
provide high quality output power with a minimal amount of
external components.
Boomer® is a registered trademark of National Semiconductor Corporation.
2
C or SPI compatible interface for control.
2
S serial interface for full
202020
Key Specifications
Features
Applications
■ 
■ 
■ 
■ 
■ 
18-bit stereo DAC
Multiple distinct output modes
Mono speaker amplifier
Stereo headphone amplifier
Mono earpiece amplifier
Differential mono analog input
Independent loudspeaker, headphone and mono earpiece
volume controls
I
Ultra low shutdown current
Click and Pop Suppression circuit
Cell Phones
PDAs
P
P
P
Shutdown current
SNR (DAC + Amplifier)
2
C/SPI (selectable) compatible interface
OUT
OUT
OUT
, BTL, 8Ω, 3.3V, 1%
H/P, 32Ω, 3.3V, 1%
Mono Earpiece, 32Ω, 1%
November 1, 2007
www.national.com
520mW (typ)
36mW (typ)
55mW (typ)
0.6µA (typ)
85dB (typ)

Related parts for LM4937RL/NOPB

LM4937RL/NOPB Summary of contents

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... The full range music path features an SNR of 85dB with a 192kHz playback. Boomer audio power amplifiers are designed specifically to provide high quality output power with a minimal amount of external components. Boomer® registered trademark of National Semiconductor Corporation. © 2007 National Semiconductor Corporation Key Specifications ■  P OUT ■ ...

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Block Diagram FIGURE 1. Audio Sub-System Block Diagram with OCL HP Outputs www.national.com (HP outputs may also be configured as cap-coupled) 2 20202001 ...

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Connection Diagrams 36 – Bump Micro SMD Top View (Bump Side Down) Order Number LM4937TL See NS Package Number TLA36LVA 36 – Bump Micro SMD Top View (Bump Side Down) Order Number LM4937RL See NS Package Number RLA36LVA 36 – ...

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Pin Descriptions Pin Pin Name Digital/ Analog A1 DGND D A2 MCLK D A3 I2S_WS D A4 SDA/SDI D A5 DVDD D A6 VDD_IO D B1 PLL_VDD D B2 I2S_SDATA D B3 I2S_CLK D B4 GPIO D B5 I2C_VDD D ...

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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Analog Supply Voltage Digital Supply Voltage Storage Temperature Input Voltage Power Dissipation (Note 3) ESD Susceptibility (Note 4) ESD Susceptibility (Note 5) Junction Temperature ...

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Audio Amplifier Electrical Characteristics AV The following specifications apply for the circuit shown in Figure 1 with all programmable gain set at 0dB, unless otherwise specified. Limits apply for T = 25°C. A Symbol Parameter I Supply Current DD I ...

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Volume Control Electrical Characteristics The following specifications apply for 3. 25°C. A Symbol Parameter Stereo Analog Inputs PreAmp Gain Setting Range PGR Differential Mono Analog Input PreAmp Gain Setting Range Output Volume Control for VCR Loudspeaker, Headphone Output, ...

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Symbol Parameter ≤ ≤ SPI (1. 2.2V Maximum SPI Frequency SPI t SPI Data Setup Time SPISETD t SPI ENB Setup Time SPISETENB t SPI Data Hold Time SPIHOLDD t SPI ENB Hold ...

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Symbol Parameter V Digital Input High Voltage IH V Digital Input Low Voltage IL Note 1: All voltages are measured with respect to the GND pin unless otherwise specified. Note 2: Absolute Maximum Ratings indicate limits beyond which damage to ...

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Output Noise AV = 5.0V and AV DD MODE PSRR AV = 3.0V 217Hz ripple MODE EP(Typ ...

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System Control The LM4937 is controlled via either a two wire I This interface is used to configure the operating mode, interfaces, data converters, mixers and amplifiers. The LM4937 is controlled by writing 8 bit data into a series of ...

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When the part is configured ADDR is low then the address portion of the I address input should be set to write to 1110000 Chip Address 0 EC ADR = ...

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System Controls TABLE 7. Loudspeaker, Earpiece, HP Left or Right Volume Control EP_VOL_4, EP_VOL_3, LS_VOL_4, LS_VOL_3, HP_L_VOL_4, HP_L_VOL_3, HP_R_VOL_4 HP_R_VOL_3 ...

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Mode CD3 CD2 — Shutdown M — Mono Differential Input AL — Analog Left Channel ...

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Loudspeaker Headphone Left Channel Headphone Right Channel Earpiece All Outputs TABLE 10. Mono Differential Amplifier Input Gain Select (08h) MONO_IN_GAIN_2 MONO_IN_GAIN_1 TABLE 11. Analog Single-Ended Input Amplifier Gain Select (07h) ANA_L_GAIN_2 ANA_L_GAIN_1 ...

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PLL Configuration Registers PLL M DIVIDER CONFIGURATION REGISTER This register is used to control the input divider of the PLL. PLL_M (0Ah) (Set = logic 1, Clear = logic 0) Bits Register 6:0 PLL_M NOTES: The M divider should be ...

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PLL_P (0Dh) (Set = logic 1, Clear = logic 0) Bits Register 3:0 PLL_P NOTES: The output of this divider should be either 12 or 24MHz in USB mode or 11.2896MHz, 12.288MHz or 24.576MHz in non-USB modes. The division of ...

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Further Notes on PLL Programming The sigma-delta PLL is designed to drive audio circuits requiring accurate clock frequencies 25MHz with frequency errors noise-shaped away from the audio band. The 5 bits of modulus control provide exact synchronization ...

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If the user needs to obtain a clock unrelated to those described above, the following method is advised. An example of obtaining 11.2896 from 12.000MHz is shown below. Choose a small range that the VCO frequency is ...

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Bits Register 7:4 R_DIV By default the stereo DAC operates at 250*fs, i.e. 12.000MHz (at the clock generator input clock) for 48kHz data expected that the PLL be used to drive the audio system unless a 12.000MHz master ...

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Common Clock Settings for the DAC The DAC can work in 4 modes, each with different oversampling rates, 125,128,64 & 32. In normal operation 125x oversampling provides for the simplest clocking solution as it will work from 12.000MHz (common in ...

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R_DIV Divide Value DAC Clock Generator Input Frequency <MHz> 1 The R divider can also be used along with the P divider in order to create the clock needed to support low sample rates. www.national.com ...

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DAC Setup Register This register is used to configure the basic operation of the stereo DAC.   DAC_SETUP (0Eh) (Set = logic 1, Clear = logic 0) Bits Register 1:0 DAC_MODE 2 MUTE_L 3 MUTE_R 4 DITHER_OFF 5 DITHER ALWAYS_ON ...

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Interface Control Register This register is used to control the I2S and I INTERFACE (0Fh) (Set = logic 1, Clear = logic 0) Bits NOTES: The master I2S format depends on the DAC mode. In USB ...

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FIR Compensation Filter Configuration Registers These registers are used to configure the DAC’s FIR com- pensation filter. Three 16 bit coefficients are required and → COMP_COEFF (10h 15h) (Set = logic 1, Clear = logic 0) Address Register 10h COMP_COEFF0_LSB ...

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Typical Performance Characteristics THD+N vs Frequency = 32Ω, P 3.0V EP Out THD+N vs Frequency = 8Ω, P 3.0V LS Out THD+N vs Frequency = 16Ω, P 5.0V HP Out www.national.com = 20mW O ...

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THD+N vs Frequency = 8Ω, P 5.0V LS Out 500mW L O 20202071 THD+N vs Output Power = 32Ω 1kHz 3.0V EP Out 20202073 THD+N vs Output Power = 32Ω 1kHz 3.0V ...

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THD+N vs Output Power = 16Ω 1kHz 5.0V EP Out THD+N vs Output Power = 16Ω 1kHz 5.0V HP Out THD+N vs Output Power = 8Ω 1kHz 5.0V LS Out, ...

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THD+N vs I2S Level HP Out 20202084 PSRR vs Frequency 3.0V EP Out Mode 1 20202086 PSRR vs Frequency 3.0V HP Out Mode 2 20202088 THD+N vs I2S Level LS Out PSRR vs Frequency 3.0V EP Out Mode 4 PSRR ...

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PSRR vs Frequency 3.0V LS Out Mode 2 PSRR vs Frequency 5.0V HP Out Mode 2 PSRR vs Frequency 5.0V LS Out Mode 4 www.national.com PSRR vs Frequency 3.0V LS Out Mode 4 20202090 PSRR vs Frequency 5.0V HP Out ...

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Output Power vs Supply Voltage = 32Ω, 1% THD+N EP Out , R L 20202096 Output Power vs Supply Voltage = 8Ω, 1% THD+N LS Out , R L 20202098 Output Power vs Supply Voltage = 32Ω, 1% THD+N HP ...

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Application Information The LM4937 supports both master and slave I2S transmis- sion at either bits per word at clock rates up to MONO ONLY SETTING The LM4937 may be restricted to mono amplification only ...

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S2 connects the center amplifer HPCOUT to the headphone ring when in OCL mode. S4 connects the center ring to GND when cap-coupled mode is desired. S4 must be removed for OCL mode to function properly. Jumper settings ...

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Demonstration Board Schematic www.national.com 36 ...

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Revision History Rev 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Date 10/04/06 Initial release. 10/13/06 Text edits. 12/15/06 Changed the datasheet title from RF Resistant Topology to RF Suppression. 02/09/07 Replaced curve (THD+N vs Output Power ...

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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 36-Bump micro SMD Order Number LM4937TL NS Package Number TLA36LVA = 3255±30μm, = 3510±30μ 600±75μ ...

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SMD Order Number LM4937RL NS Package Number RLA36LVA = 3255±30μm, = 3510±30μ 600±75μ www.national.com ...

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... For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock Conditioners www.national.com/timing Data Converters www.national.com/adc Displays www.national.com/displays Ethernet www.national.com/ethernet Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www ...

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