LM49370 Audio Sub-System with an Ultra Low EMI, Spread Spectrum, Class D Loudspeaker Amplifier, a Dual-Mode Stereo Headphone Amplifier, and a Dedicated PCM Interface for Bluetooth Transceivers 1.0 General Description The LM49370 is an integrated audio subsystem that supports both analog and digital audio functions. The LM49370 includes a high quality stereo DAC, a mono ADC, a stereo headphone amplifier, which supports output cap-less (OCL) or AC-coupled (SE) modes of operation, a mono earpiece amplifier, and an ultra-low EMI spread spectrum Class D loudspeaker amplifier. It is designed for demanding applications in mobile phones and other portable devices. The LM49370 features a bi-directional I2S interface and a bidirectional PCM interface for full range audio on either interface. The LM49370 utilizes an I2C or SPI compatible interface for control. The stereo DAC path features an SNR of 85 dB with an 18-bit 48 kHz input. In SE mode the headphone amplifier delivers at least 33 mWRMS to a 32Ω single-ended stereo load with less than 1% distortion (THD+N) when A_VDD = 3.3V. The mono earpiece amplifier delivers at least 115mWRMS to a 32Ω bridged-tied load with less than 1% distortion (THD+N) when A_VDD = 3.3V. The mono speaker amplifier delivers up to 490mW into an 8Ω load with less than 1% distortion when LS_VDD = 3.3V and up to 1.2W when LS_VDD = 5.0V. The LM49370 employs advanced techniques to reduce power consumption, to reduce controller overhead, to speed development time, and to eliminate click and pop. Boomer audio power amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. It is therefore ideally suited for mobile phone and other low voltage applications where minimal power consumption, PCB area and cost are primary requirements. 2.0 Applications ■ ■ ■ ■ ■ Smart phones Mobile Phones and Multimedia Terminals PDAs, Internet Appliances and Portable Gaming Portable DVD/CD/AAC/MP3 Players Digital Cameras/Camcorders 3.0 Key Specifications ■ ■ ■ ■ ■ ■ ■ PHP (AC-COUP) (A_VDD = 3.3V, 32Ω, 1% THD) PHP (OCL) (A_VDD = 3.3V, 32Ω, 1% THD) PLS ( LS_VDD = 5V, 8Ω, 1% THD) PLS (LS_VDD = 4.2V, 8Ω, 1% THD) PLS (LS_VDD = 3.3V, 8Ω, 1% THD) Shutdown Current PSRRLS (217 Hz, LS_VDD = 3.3V) 33 mW 31 mW 1.2 W 900 mW 490 mW 0.8 µA 70 dB ■ ■ ■ ■ SNRLS (AUX IN to Loudspeaker) SNRDAC (Stereo DAC to AUXOUT) SNRADC (Mono ADC from Cell Phone In) SNRHP (Aux In to Headphones) 90 dB (typ) 85 dB (typ) 90 dB (typ) 98 dB (typ) 4.0 Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Spread Spectrum Class D architecture reduces EMI Mono Class D 8Ω amplifier, 490 mW at 3.3V OCL or AC-coupled headphone operation 33mW stereo headphone amplifier at 3.3V 115 mW earpiece amplifier at 3.3V 18-bit stereo DAC 16-bit mono ADC 8 kHz to 192 kHz stereo audio playback 8 kHz to 48 kHz mono recording Bidirectional I2S compatible audio interface Bidirectional PCM compatible audio interface for Bluetooth transceivers I2S-PCM Bridge with sample rate conversion Sigma-Delta PLL for operation from any clock at any sample rate Digital 3D Stereo Enhancement FIR filter programmability for simple tone control Low power clock network operation if a 12 MHz or 13 MHz system clock is available Read/write I2C or SPI compatible control interface Automatic headphone & microphone detection Support for internal and external microphones Automatic gain control for microphone input Differential audio I/O for external cellphone module Mono differential auxiliary output Stereo auxiliary inputs Differential microphone input for internal microphone Flexible audio routing from input to output 32 Step volume control for mixers in 1.5 dB steps 16 Step volume control for microphone in 2 dB steps Programmable sidetone attenuation in 3 dB steps Two configurable GPIO ports Multi-function IRQ output Micro-power shutdown mode Available in the 4 x 4 mm 49 bump micro SMDxt package Boomer® is a registered trademark of National Semiconductor Corporation. © 2007 National Semiconductor Corporation 201917 www.national.com LM49370 Audio Sub-System with an Ultra Low EMI, Spread Spectrum, Class D Loudspeaker Amplifier, a Dual-Mode Stereo Headphone Amplifier, and a Dedicated PCM Interface for Bluetooth Transceivers February 2007 LM49370 5.0 LM49370 Overview 20191724 FIGURE 1. Conceptual Schematic www.national.com 2 LM49370 6.0 Typical Application 20191723 FIGURE 2. Example Application in Multimedia Mobile Phone 3 www.national.com LM49370 Table of Contents 1.0 General Description ......................................................................................................................... 2.0 Applications .................................................................................................................................... 3.0 Key Specifications ........................................................................................................................... 4.0 Features ........................................................................................................................................ 5.0 LM49370 Overview .......................................................................................................................... 6.0 Typical Application ........................................................................................................................... 7.0 Connection Diagrams ....................................................................................................................... 7.1 PIN TYPE DEFINITIONS ................................................................................................................ 8.0 Absolute Maximum Ratings .............................................................................................................. 9.0 Operating Ratings ........................................................................................................................... 10.0 Electrical Characteristics (Notes 1, 2) Unless otherwise stated PLL_VDD = 3.3V, D_VDD = 3.3V, BB_VDD = 1.8V, 1 1 1 1 2 3 5 7 8 8 A_VDD = 3.3V, LS_VDD = 3.3V. The following specifications apply for the circuit shown in Figure 2 unless otherwise stated. Limits apply for 25°C. .............................................................................................................................. 8 11.0 System Control ............................................................................................................................ 11.1 I2C SIGNALS ............................................................................................................................ 11.2 I2C DATA VALIDITY .................................................................................................................. 11.3 I2C START AND STOP CONDITIONS .......................................................................................... 11.4 TRANSFERRING DATA ............................................................................................................. 11.5 I2C TIMING PARAMETERS ....................................................................................................... 12.0 Status & Control Registers ............................................................................................................ 12.1 BASIC CONFIGURATION REGISTER ......................................................................................... 12.2 CLOCKS CONFIGURATION REGISTER ...................................................................................... 12.3 LM49370 CLOCK NETWORK ..................................................................................................... 12.4 COMMON CLOCK SETTINGS FOR THE DAC & ADC ................................................................... 12.5 PLL M DIVIDER CONFIGURATION REGISTER ............................................................................ 12.6 PLL N DIVIDER CONFIGURATION REGISTER ............................................................................ 12.7 PLL P DIVIDER CONFIGURATION REGISTER ............................................................................ 12.8 PLL N MODULUS CONFIGURATION REGISTER ......................................................................... 12.9 FURTHER NOTES ON PLL PROGRAMMING ............................................................................... 12.10 ADC_1 CONFIGURATION REGISTER ....................................................................................... 12.11 ADC_2 CONFIGURATION REGISTER ....................................................................................... 12.12 AGC_1 CONFIGURATION REGISTER ...................................................................................... 12.13 AGC_2 CONFIGURATION REGISTER ...................................................................................... 12.14 AGC_3 CONFIGURATION REGISTER ...................................................................................... 12.15 AGC OVERVIEW ..................................................................................................................... 12.16 MIC_1 CONFIGURATION REGISTER ........................................................................................ 12.17 MIC_2 CONFIGURATION REGISTER ........................................................................................ 12.18 SIDETONE ATTENUATION REGISTER ..................................................................................... 12.19 CP_INPUT CONFIGURATION REGISTER ................................................................................. 12.20 AUX_LEFT CONFIGURATION REGISTER ................................................................................. 12.21 AUX_RIGHT CONFIGURATION REGISTER ............................................................................... 12.22 DAC CONFIGURATION REGISTER .......................................................................................... 12.23 CP_OUTPUT CONFIGURATION REGISTER .............................................................................. 12.24 AUX_OUTPUT CONFIGURATION REGISTER ............................................................................ 12.25 LS_OUTPUT CONFIGURATION REGISTER .............................................................................. 12.26 HP_OUTPUT CONFIGURATION REGISTER .............................................................................. 12.27 EP_OUTPUT CONFIGURATION REGISTER .............................................................................. 12.28 DETECT CONFIGURATION REGISTER .................................................................................... 12.29 HEADSET DETECT OVERVIEW ............................................................................................... 12.30 STATUS REGISTER ................................................................................................................ 12.31 3D CONFIGURATION REGISTER ............................................................................................. 12.32 I2S PORT MODE CONFIGURATION REGISTER ........................................................................ 12.33 I2S PORT CLOCK CONFIGURATION REGISTER ....................................................................... 12.34 DIGITAL AUDIO DATA FORMATS ............................................................................................. 12.35 PCM PORT MODE CONFIGURATION REGISTER ...................................................................... 12.36 PCM PORT CLOCK CONFIGURATION REGISTER ..................................................................... 12.37 SRC CONFIGURATION REGISTER .......................................................................................... 12.38 GPIO CONFIGURATION REGISTER ......................................................................................... 12.39 DAC PATH COMPENSATION FIR CONFIGURATION REGISTERS .............................................. 13.0 Typical Performance Characteristics .............................................................................................. 14.0 LM49370 Demonstration Board Schematic Diagram ......................................................................... 15.0 Demoboard PCB Layout ............................................................................................................... 16.0 Revision History .......................................................................................................................... 17.0 Physical Dimensions .................................................................................................................... www.national.com 4 14 14 14 14 14 16 18 19 20 21 22 23 24 25 26 27 30 31 32 33 34 35 36 37 38 38 39 39 40 41 41 41 42 42 43 44 47 48 49 50 51 52 53 54 56 56 58 91 92 98 99 LM49370 7.0 Connection Diagrams 49 Bump micro SMDxt 49 Bump micro SMDxt Marking 201917q7 Top View XY — Date Code TT — Die Traceability G — Boomer I3 — LM49370RL 201917p3 Top View (Bump Side Down) Order Number LM49370RL See NS Package Number RLA49UUA 5 www.national.com LM49370 Pin Descriptions Pin Pin Name Type Direction A1 EP_NEG Analog Output Description Earpiece negative output A2 A_VDD Supply Input Headphone and mixer VDD A3 INT_MIC_POS Analog Input Internal microphone positive input A4 PCM_SDO Digital Output A5 PCM_CLK Digital Inout PCM clock signal A6 PCM_SYNC Digital Inout PCM sync signal A7 PCM_SDI Digital Input PCM Serial Data Input Headphone and mixer ground PCM Serial Data Output B1 A_VSS Supply Input B2 EP_POS Analog Output B3 INT_MIC_NEG Analog Input Internal microphone negative input B4 BYPASS Earpiece positive output Analog Input A_VDD/2 filter point B5 TEST_MODE/CS Digital Input If SPI_MODE = 1, then this pin becomes CS. B6 PLL_FILT Analog Input Filter point for PLL VCO input B7 PLL_VDD Supply Input PLL VDD C1 HP_R Analog Output Headphone Right Output C2 EXT_BIAS Analog Output External microphone supply (2.0/2.5/2.8/3.3V) C3 INT_BIAS Analog Output Internal microphone supply (2.0/2.5/2.8/3.3V) C4 AUX_R Analog Input Right Analog Input C5 GPIO_2 Digital Inout General Purpose I/O 2 C6 SDA Digital Inout Control Data, I2C_SDA or SPI_SDA C7 SCL Digital Input Control Clock, I2C_SCL or SPI_SCL D1 HP_L Analog Output D2 VREF_FLT Analog Inout Filter point for the microphone power supply D3 EXT_MIC Analog Input External microphone input D4 SPI_MODE Digital Input Control mode select 1 = SPI, 0 = I2C D5 GPIO_1 Digital Inout General Purpose I/O 1 D6 BB_VDD Supply Input Baseband VDD for the digital I/Os Headphone Left Output D7 D_VDD Supply Input Digital VDD E1 HP_VMID Analog Inout Virtual Ground for Headphones in OCL mode, otherwise 1st headset detection input E2 MIC_DET Analog Input Headset insertion/removal and microphone presence detection input. E3 AUX_L Analog Input Left Analog Input E4 CPI_NEG Analog Input Cell Phone analog input negative E5 IRQ Digital Output Interrupt request signal (NOT open drain) E6 I2S_SDO Digital Output I2S Serial Data Out E7 I2S_SDI Digital Input I2S Serial Data Input F1 HP_VMID_FB Analog Input VMID Feedback in OCL mode, otherwise a 2nd headset detection input F2 LS_VDD Supply Input Loudspeaker VDD F3 CPI_POS Analog Input Cell Phone analog input positive F4 CPO_NEG Analog Output Cell Phone analog output negative F5 AUX_OUT_NEG Analog Output Auxiliary analog output negative F6 I2S_WS Digital Inout I2S Word Select Signal (can be master or slave) F7 I2S_CLK Digital Inout I2S Clock Signal (can be master or slave) G1 LS_NEG Analog Output Loudspeaker negative output G2 LS_VSS Supply Input G3 LS_POS Analog Output Loudspeaker positive output G4 CPO_POS Analog Output Cell Phone analog output positive G5 AUX_OUT_POS Analog Output Auxiliary analog output positive www.national.com Loudspeaker ground 6 Pin Name Type Direction G6 D_VSS Supply Input Digital ground G7 MCLK Digital Input Input clock from 0.5 MHz to 30 MHz LM49370 Pin Description Digital Input— 7.1 PIN TYPE DEFINITIONS Analog Input— A pin that is used by the analog and is never driven by the device. Supplies are part of this classification. Analog Output— A pin that is driven by the device and should not be driven by external sources. Analog Inout— A pin that is typically used for filtering a DC signal within the device, Passive components can be connected to these pins. Digital Output— Digital Inout— 7 A pin that is used by the digital but is never driven. A pin that is driven by the device and should not be driven by another device to avoid contention. A pin that is either open drain (I2C_SDA) or a bidirectional CMOS in/out. In the later case the direction is selected by a control register within the LM49370. www.national.com LM49370 Junction Temperature Thermal Resistance θJA – RLA49 (soldered down to PCB with 2in2 1oz. copper plane) Soldering Information 8.0 Absolute Maximum Ratings (Notes 1, 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Analog Supply Voltage (A_VDD & LS_VDD) Digital Supply Voltage (BB_VDD & D_VDD & PLL_VDD) Storage Temperature Power Dissipation (Note 3) ESD Susceptibility Human Body Model (Note 4) Machine Model (Note 5) 150°C 60°C/W 9.0 Operating Ratings 6.0V Temperature Range Supply Voltage D_VDD/PLL_VDD BB_VDD LS_VDD/A_VDD 6.0V −65°C to +150°C Internally Limited −40°C to +85°C 2.5V to 4.5V 1.8V to 4.5V 2.5V to 5.5V 2500V 200V 10.0 Electrical Characteristics (Notes 1, 2) Unless otherwise stated PLL_VDD = 3.3V, D_VDD = 3.3V, BB_VDD = 1.8V, A_VDD = 3.3V, LS_VDD = 3.3V. The following specifications apply for the circuit shown in Figure 2 unless otherwise stated. Limits apply for 25°C. LM49370 Symbol Parameter Conditions Typical (Note 6) Limit (Notes 7, 11) Units POWER DISD Digital Shutdown Current Chip Mode '00', fMCLK = 13MHz 0.7 2.2 µA (max) DIST Digital Standby Current Chip Mode '01', fMCLK = 13MHz 0.9 1.8 mA(max) AISD Analog Shutdown Current Chip Mode '00' 0.1 1.2 µA(max) AIST Analog Standby Current Chip Mode '01' 0.1 1.2 µA (max) Chip Mode '10', fMCLK = 12MHz, fS = 48kHz, DAC on; PLL off 7.9 Chip Mode '10', fMCLK = 13MHz, fPLLOUT = 12MHz, fS = 48kHz; DAC + PLL on 12.5 14.5 mA(max) Chip Mode '10', HP On, SE mode, DAC inputs selected 9.0 13.5 mA(max) Chip Mode '10', HP On, OCL mode, DAC inputs selected 9.4 13.5 mA(max) Chip Mode '10', LS On, DAC inputs selected 11.5 15.5 mA(max) Chip Mode '10', fMCLK = 13MHz, DAC +ADC + PLL off 0.9 1.8 mA(max) Chip Mode '10', HP On, SE mode, AUX inputs selected 5.9 9.5 mA(max) Chip Mode '10', HP On, OCL mode, AUX inputs selected 6.3 9.7 mA(max) Chip Mode '10', LS On, AUX inputs selected 8.4 12 mA(max) Chip Mode '10', fMCLK = 13MHz, fS = 8kHz, DAC +ADC on; PLL Off 2.7 3.5 mA(max) CODEC Mode Analog Active Current Chip Mode '10', EP On, DAC inputs selected 11.2 15.5 mA(max) Voice Module Mode Digital Active Current Chip Mode '10', fMCLK = 13MHz, DAC +ADC + PLL off 0.9 1.8 mA(max) Voice Module Mode Analog Active Current Chip Mode '10', EP + CPOUT on, CPIN input selected 7.4 11 mA(max) Digital Playback Mode Digital Active Current Digital Playback Mode Analog Active Current Analog Playback Mode Digital Active Current Analog Playback Mode Analog Active Current CODEC Mode Digital Active Current www.national.com 8 mA Symbol Parameter Conditions Typical (Note 6) Limit (Notes 7, 11) Units LOUDSPEAKER AMPLIFIER PLS Max Loudspeaker Power LSTHD+N Loudspeaker Harmonic Distortion LSEFF Efficiency PSRRLS 8Ω load, LS_VDD = 5V 1.2 W 8Ω load, LS_VDD = 4.2V 0.9 W 8Ω load, LS_VDD = 3.3V 0.5 8Ω load, LS_VDD = 3.3V, 0.43 W (min) 0.04 % 0 dB Input MCLK = 12.000 MHz 84 % Power Supply Rejection Ration (Loudspeaker) AUX inputs terminated CBYPASS = 1.0 µF VRIPPLE = 200 mVP-P fRIPPLE = 217 Hz 70 dB SNRLS Signal to Noise Ratio From 0 dB Analog AUX input, A-weighted 90 eN Output Noise A-weighted 62 µV VOS Loudspeaker Offset Voltage 12 mV PO = 400mW 80 dB(min) HEADPHONE AMPLIFIER PHP PSRRHP Headphone Power Power Supply Rejection Ratio (Headphones) mW (min) 32Ω load, 3.3V, SE 33 16Ω load, 3.3V, SE 52 mW 32Ω load, 3.3V, OCL, VCM = 1.5V 31 mW 32Ω load, 3.3V, OCL, VCM = 1.2V 20 mW 16Ω load, 3.3V, OCL, VCM = 1.5V 50 mW 16Ω load, 3.3V, OCL, VCM = 1.2V 32 mW SE Mode 60 dB OCL Mode VCM = 1.2V 68 OCL Mode VCM = 1.5V 65 dB SE Mode 98 dB OCL Mode VCM = 1.2V 97 dB OCL Mode VCM = 1.5V 96 dB 25 AUX inputs terminated CBYPASS = 1.0 µF VRIPPLE = 200 mVP-P fRIPPLE = 217 Hz 55 dB(min) From 0dB Analog AUX input A-weighted SNRHP Signal to Noise Ratio HPTHD+N Headphone Harmonic Distortion 32Ω load, 3.3V, PO = 7.5mW eN Output Noise A-weighted ΔACH-CH Stereo Channel-to-Channel Gain Mismatch XTALK Stereo Crosstalk VOS Offset Voltage 0.05 % 12 µV 0.3 dB SE Mode 61 dB OCL Mode 71 dB 8 mV EARPIECE AMPLIFIER 9 www.national.com LM49370 LM49370 LM49370 LM49370 Symbol PEP Typical (Note 6) Limit (Notes 7, 11) 32Ω load, 3.3V 115 100 16Ω load, 3.3V 150 mW 76 dB 93 dB Parameter Earpiece Power Conditions PSRREP Power Supply Rejection Ratio (Earpiece) CP_IN terminated CBYPASS = 1.0 µF VRIPPLE = 200 mVP-P FRIPPLE = 217 Hz SNREP Signal to Noise Ratio From 0dB Analog AUX input, A-weighted EPTHD+N Earpiece Harmonic Distortion 32Ω load, 3.3V, PO = 50mW eN Output Noise A-weighted VOS Offset Voltage Units mW (min) 0.04 % 41 µV 8 mV 0.02 % 86 dB 0.02 % 86 dB AUXOUT AMPLIFIER THD+N PSRR Total Harmonic Distortion + Noise VO = 1VRMS, 5kΩ load Power Supply Rejection Ratio CP_IN terminated CBYPASS = 1.0μF VRIPPLE = 200mVPP fRIPPLE = 217Hz CP_OUT AMPLIFIER THD+N Total Harmonic Distortion + Noise VO = 1VRMS, 5kΩ load PSRR Power Supply Rejection Ratio CBYPASS = 1.0μF VRIPPLE = 200mVPP fRIPPLE = 217Hz MONO ADC RADC PBADC ADC Ripple ADC Passband SBAADC ADC Stopband Attenuation SNRADC ADC Signal to Noise Ratio ADCLEVEL ADC Full Scale Input Level ±0.25 dB Lower (HPF Mode 1), fS = 8 kHz 300 Hz Upper 3470 Hz Above Passband 60 dB HPF Notch, 50 Hz/60 Hz (worst case) 58 dB From CPI, A-weighted 90 dB 1 VRMS STEREO DAC RDAC DAC Ripple 0.1 dB PBDAC DAC Passband 20 kHz SBADAC DAC Stopband Attenuation 70 dB SNRDAC DAC Signal to Noise Ratio 85 dB DRDAC DAC Dynamic Range 96 dB DACLEVEL DAC Full Scale Output Level 1 VRMS A-weighted, AUXOUT PLL FIN Input Frequency Range Min 0.5 MHz Max 30 MHz I2S/PCM fS = 48kHz; 16 bit mode fI2SCLK www.national.com I2S CLK Frequency 1.536 MHz fS = 48kHz; 25 bit mode 2.4 MHz fS = 8kHz; 16 bit mode 0.256 MHz fS = 8kHz; 25 bit mode 0.4 MHz 10 Symbol fPCMCLK Parameter PCM CLK Frequency DCI2S_CLK I2S_CLK Duty Cycle DCI2S_WS I2S_WS Duty Cycle Conditions Typical (Note 6) Limit (Notes 7, 11) Units fS = 48kHz; 16 bit mode 0.768 MHz fS = 48kHz; 25 bit mode 1.2 MHz fS = 8kHz; 16 bit mode 0.128 MHz fS = 8kHz; 25 bit mode 0.2 MHz Min 40 % (min) Max 60 % (max) 50 % I2C TI2CSET I2C Data Setup Time Refer to Pg. 16 for more details 100 ns (min) TI2CHOLD I2C Data Hold Time Refer to Pg. 16 for more details 300 ns (min) SPI TSPISETENB Enable Setup Time 100 ns (min) TSPIHOLD-ENB Enable Hold Time 100 ns (min) TSPISETD Data Setup Time 100 ns (min) TSPIHOLDD Data Hold Time 100 ns (min) TSPICL Clock Low Time 500 ns (min) TSPICH Clock High Time 500 ns (min) VOLUME CONTROL Minimum Gain w/ AUX_BOOST OFF VCRAUX VCRDAC AUX Volume Control Range DAC Volume Control Range Maximum Gain w/ AUX_BOOST OFF CPIN Volume Control Range VCRMIC MIC Volume Control Range dB 0 dB Minimum Gain w/ AUX_BOOST ON –34.5 dB Maximum Gain w/ AUX_BOOST ON 12 dB Minimum Gain w/ DAC_BOOST OFF –46.5 dB Maximum Gain w/ DAC_BOOST OFF 0 dB –34.5 dB Minimum Gain w/ DAC_BOOST ON Maximum Gain w/ DAC_BOOST ON VCRCPIN –46.5 12 dB Minimum Gain –34.5 dB Maximum Gain 12 dB Minimum Gain 6 dB Maximum Gain 36 dB Minimum Gain –30 dB Maximum Gain 0 dB VCRSIDE SIDETONE Volume Control Range SSAUX AUX VCR Stepsize 1.5 dB SSDAC DAC VCR Stepsize 1.5 dB SSCPIN CPIN VCR Stepsize 1.5 dB SSMIC MIC VCR Stepsize 2 dB SSSIDE SIDETONE VCR Stepsize 3 dB AUDIO PATH GAIN W/ STEREO (bit 6 of 0x00h) ENABLED (AUX_L & AUX_R signals identical and selected onto mixer) Loudspeaker Audio Path Gain Minimum Gain from AUX input, BOOST OFF –34.5 dB Maximum Gain from AUX input, BOOST OFF 12 dB Minimum Gain from CPI input –22.5 dB Maximum Gain from CPI input 24 dB 11 www.national.com LM49370 LM49370 LM49370 LM49370 Symbol Parameter Headphone Audio Path Gain Earpiece Audio Path Gain AUXOUT Audio Path Gain Conditions www.national.com Limit (Notes 7, 11) Units Minimum Gain from AUX input, BOOST OFF –52.5 dB Maximum Gain from AUX input, BOOST OFF –6 dB Minimum Gain from CPI input –40.5 dB Maximum Gain from CPI input 6 dB Minimum Gain from MIC input using SIDETONE path w/ VCRMIC gain = 6dB –30 dB Maximum Gain from MIC input using SIDETONE path w/ VCRMIC gain = 6dB 0 dB Minimum Gain from AUX input, BOOST OFF –40.5 dB Maximum Gain from AUX input, BOOST OFF 6 dB Minimum Gain from CPI input –28.5 dB Maximum Gain from CPI input 18 dB Minimum Gain from MIC input using SIDETONE path w/ VCRMIC gain = 6dB –18 dB Maximum Gain from MIC input using SIDETONE path w/ VCRMIC gain = 6dB 12 dB Minimum Gain from AUX input, BOOST OFF –46.5 dB Maximum Gain from AUX input, BOOST OFF 0 dB –34.5 dB Maximum Gain from CPI input 12 dB Minimum Gain from AUX input, BOOST OFF –46.5 dB Maximum Gain from AUX input, BOOST OFF 0 dB Minimum Gain from MIC input 6 dB Maximum Gain from MIC input 36 dB Minimum Gain from CPI input CPOUT Audio Path Gain Typical (Note 6) 12 Symbol Parameter Conditions Typical (Note 6) Limit (Notes 7, 11) Units Total DC Power Dissipation DAC (fS = 48kHz) and HP ON Digital Playback Mode Power Dissipation Analog Playback Mode Power Dissipation VOICE CODEC Mode Power Dissipation VOICE Module Mode Power Dissipation fMCLK = 12MHz, PLL OFF 56 mW fMCLK = 13MHz, PLL ON fPLLOUT = 12MHz 71 mW 22 mW 46 mW 27 mW AUX Inputs selected and HP ON fMCLK = 13MHz, PLL OFF PCM DAC (fS = 8kHz) + ADC (fS = 8kHz) and EP ON fMCLK = 13MHz, PLL OFF CP IN selected. EP and CPOUT ON fMCLK = 13MHz, PLL OFF Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional but do not guarantee specific performance limits. Characteristics state DC and AC electrical specifications under particular test conditions which guarantee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where no limit is given, however, the typical value is a good indication of device performance. Note 2: All voltages are measured with respect to the relevant VSS pin unless otherwise specified. All grounds should be coupled as close as possible to the device. Note 3: The maximum power dissipation must be de-rated at elevated temperatures and is dictated by TJMAX, θJA, and the ambient temperature, TA. The maximum allowable power dissipation is PDMAX = (TJMAX – TA)/ θJA or the number given in Absolute Maximum Ratings, whichever is lower. Note 4: Human body model: 100pF discharged through a 1.5kΩ resistor. Note 5: Machine model: 220pF – 240pF discharged through all pins. Note 6: Typical values are measured at 25°C and represent the parametric norm. Note 7: Limits are guaranteed to Nationals AOQL (Average Outgoing Quality Level). Note 8: Best operation is achieved by maintaining 3.0V < A_VDD < 5.0 and 3.0V < D_VDD < 3.6V and A_VDD > D_VDD. Note 9: Digital shutdown current is measured with system clock set for PLL output while the PLL is disabled. Note 10: Disabling or bypassing the PLL will usually result in an improvement in noise measurements. Note 11: Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis. 13 www.national.com LM49370 LM49370 LM49370 11.0 System Control Method 1. I2C Compatible Interface 11.1 I2C SIGNALS In I2C mode the LM49370 pin SCL is used for the I2C clock SCL and the pin SDA is used for the I2C data signal SDA. Both these signals need a pull-up resistor according to I2C specification. The I2C slave address for LM49370 is 00110102. 11.2 I2C DATA VALIDITY The data on SDA line must be stable during the HIGH period of the clock signal (SCL). In other words, state of the data line can only be changed when SCL is LOW. 201917q1 I2C Signals: Data Validity 11.3 I2C START AND STOP CONDITIONS START and STOP bits classify the beginning and the end of the I2C session. START condition is defined as SDA signal transitioning from HIGH to LOW while SCL line is HIGH. STOP condition is defined as the SDA transitioning from LOW to HIGH while SCL is HIGH. The I2C master always generates START and STOP bits. The I2C bus is considered to be busy after START condition and free after STOP condition. During data transmission, I2C master can generate repeated START conditions. First START and repeated START conditions are equivalent, function-wise. 201917q2 11.4 TRANSFERRING DATA Every byte put on the SDA line must be eight bits long, with the most significant bit (MSB) being transferred first. Each byte of data has to be followed by an acknowledge bit. The acknowledge related clock pulse is generated by the master. The transmitter releases the SDA line (HIGH) during the acknowledge clock pulse. The receiver must pull down the SDA line during the 9th clock pulse, signifying an acknowledge. A receiver which has been addressed must generate an acknowledge after each byte has been received. After the START condition, the I2C master sends a chip address. This address is seven bits long followed by an eight bit which is a data direction bit (R/W). The LM49370 address is 00110102. For the eighth bit, a “0” indicates a WRITE and a “1” indicates a READ. The second byte selects the register to which the data will be written. The third byte contains data to write to the selected register. www.national.com 14 LM49370 201917q3 I2C Chip Address Register changes take an effect at the SCL rising edge during the last ACK from slave. 201917q5 w = write (SDA = “0”) r = read (SDA = “1”) ack = acknowledge (SDA pulled down by slave) rs = repeated start Example I2C Write Cycle 15 www.national.com LM49370 When a READ function is to be accomplished, a WRITE function must precede the READ function, as shown in the Read Cycle waveform. 201917q6 Example I2C Read Cycle 201917p9 I2C Timing Diagram 11.5 I2C TIMING PARAMETERS Symbol Parameter Limit Min Units Max 1 Hold Time (repeated) START Condition 0.6 µs 2 Clock Low Time 1.3 µs 3 Clock High Time 600 ns 4 Setup Time for a Repeated START Condition 600 5 Data Hold Time (Output direction, delay generated by LM49370) 300 900 ns 5 Data Hold Time (Input direction, delay generated by the Master) 0 900 ns 6 Data Setup Time 7 Rise Time of SDA and SCL 20+0.1Cb 300 ns 8 Fall Time of SDA and SCL 15+0.1Cb 300 ns 100 9 Set-up Time for STOP condition 600 10 Bus Free Time between a STOP and a START Condition 1.3 Cb Capacitive Load for Each Bus Line 10 NOTE: Data guaranteed by design www.national.com ns 16 ns ns µs 200 pF The LM49370 can be controlled via a three wire interface consisting of a clock, data and an active low chip_select. To use this control method connect SPI_MODE to BB_VDD and use TEST_MODE/CS as the chip_select as follows: 20191706 FIGURE 3. SPI Write Transaction If the application requires read access to the register set; for example to determine the cause of an interrupt request, the GPIO2 pin can be configured as an SPI format serial data output by setting the GPIO_SEL in the GPIO configuration register (0x1Ah) to SPI_SDO. To perform a read rather than a write to a particular address the MSB of the register address field is set to a 1, this effectively mirrors the contents of the register field to read-only locations above 0x80h: 20191707 FIGURE 4. SPI Read Transaction Three Wire Mode Write Bus Timing 20191709 FIGURE 5. SPI Timing 17 www.national.com LM49370 Method 2. SPI/Microwire Control/3–wire Control LM49370 12.0 Status & Control Registers TABLE 1. Register Map (The default value of all I2C registers is 0x00h) Addre ss Register 0x00h BASIC 7 6 5 DAC_ MODE CAP_SIZE 0x01h CLOCKS 0x02h PLL_M 4 VCOFATS 0x05h PLL_MOD PLLTEST 0x08h AGC_1 0x09h AGC_2 1 OSC_ENB PLL_ENB 0 CHP_MODE DAC_CLK_SEL PLL_M PLL_N 0x04h PLL_P 0x07h ADC_2 2 R_DIV FORCERQ 0x03h PLL_N 0x06h ADC_1 3 Q_DIV HPF_MODE NGZXDD PLL_P PLL_CLK_SEL PLL_N_MOD SAMPLE_RATE ADC_CLK_SEL LEFT NG_ENB AGC_ATTACK 0x0Bh MIC_1 INT_EXT 0x0Ch MIC_2 MIC ADCMUTE ADC_MOD E AGC_TARGET AGC_DECAY 0x0Ah AGC_3 CPI PEAKTIME NOISE_GATE_THRESHOLD AGC_TIGH T RIGHT AGC_ENB AGC_MAX_GAIN AGC_HOLD_TIME SE_DIFF MUTE BTN_DEBOUNCE_TIME PREAMP_GAIN BTNTYPE 0x0Dh SIDETONE MIC_BIAS_VOLTAGE VCMVOLT SIDETONE_ATTEN 0x0Eh CP_INPUT MUTE CPI_LEVEL 0x0Fh AUX_LEFT AUX_DAC MUTE BOOST AUX_LEFT_LEVEL 0x10h AUX_RIGHT AUX_DAC MUTE BOOST AUX_RIGHT_LEVEL 0x11h DAC USAXLVL DACMUTE BOOST DAC_LEVEL MUTE LEFT RIGHT MIC 0x13h AUX OUTPUT 0x12h CP_OUTPUT MICGATE MUTE LEFT RIGHT CPI 0x14h LS_OUTPUT MUTE LEFT RIGHT CPI MUTE LEFT RIGHT CPI SIDE MUTE LEFT RIGHT CPI SIDE TEMP_INT BTN_INT DET_INT MIC STEREO HEADSET MODE 3DENB INENB OUTENB 0x15h HP_OUTPUT OCL STEREO 0x16h EP_OUTPUT 0x17h DETECT HS_DBNC_TIME 0x18h STATUS 0x19h 3D GPIN1 CUST_COM ATTENUATE P 0x1Ah I2SMODE WORD_ ORDER 0x1Bh I2SCLOCK PCM_SYNC__WIDTH 0x1Ch PCMMODE ALAW/ μLAW 0x1Dh PCMCLOCK 0x1Eh BRIDGE 0x1Fh GPIO GPIN2 TEMP FREQ I2S_WS_GEN_MODE COMPAND BTN LEVEL WS_MS STEREO REVERSE I2S_CLOCK_GEN_MODE SDO_ LSB_HZ SYNC_MS CLKSRCE PCM_SYNC_GEN_MODE MONO_SUM_MODE DAC_SRC_ MODE ADC_SRC_ MODE MONO_ SUM_SEL GPIO_2_SEL CMP_0_LSB 0x21h CMP_0_0SB CMP_0_MSB 0x22h CMP_1_LSB CMP_1_LSB 0x23h CMP_1_MSB CMP_1_MSB 0x24h CMP_2_LSB CMP_2_LSB 0x25h CMP_2_MSB CMP_2_MSB 18 CLK_MS CLKSCE CLK_MS INENB OUTENB PCM_CLOCKGEN MODE DAC_TX_SEL 0x20h CMP_0_LSB www.national.com I2S_MODE I2S_TX_SEL GPIO_1_SEL PCM_ TX_SEL LM49370 12.1 BASIC CONFIGURATION REGISTER This register is used to control the basic function of the chip. TABLE 2. BASIC (0x00h) Bits Field Description 1:0 CHIP_MODE The LM49370 can be placed in one of four modes which dictate its basic operation. When a new mode is selected the LM49370 will change operation silently and will re-configure the power management profile automatically. The modes are described as follows: CHIP MODE Audio System 002 Off Typical Application Power-down Mode 012 Off Stand-by mode with headset event detection 102 On Active without headset event detection 112 On Active with headset event detection 2 PLL_ENABLE 3 USE_OSC If set the power management and control circuits will assume that no external clock is available and will resort to using an on-chip oscillator for headset detection and analog power management functions such as click and pop. The PLL, ADC, and DAC are not wired to use this low quality clock. This bit must be cleared for the part to be fully turned off power-down mode. 5:4 CAP_SIZE This programs the extra delays required to stabilize once charge/discharge is complete, based on the size of the bypass capacitor. 7:6 DAC_MODE This enables the PLL. CAP_SIZE Bypass Capacitor Size Turn-off/on time 002 0.1 µF 45 ms/75 ms 012 1 µF 45 ms/140 ms 102 2.2 µF 45 ms/260 ms 112 4.7 µF 45 ms/500 ms The DAC can operate in one of four modes. If an “fs*2∧N” audio clock is available, then the DAC can be run in a slightly lower power mode. If such a clock is not available, the PLL can be used to generate a suitable clock. DAC MODE DAC OSR Typical Application 002 125 48kHz Playback from 12.000MHz 012 128 48kHz Playback from 12.288MHz 102 64 96kHz Playback from 12.288MHz 112 32 192kHz Playback from 24.576MHz For reliable headset / push button detection the following bits should be defined before enabling the headset detection system by setting bit 0 of CHIP_MODE: The OCL-bit (Cap / Capless headphone interface; bit 6 of HP_OUTPUT (0x15h)) The headset insert/removal debounce settings (bits 6:3 of DETECT (0x17h)) The BTN_TYPE-bit (Parallel / Series push button type; bit 3 MIC_2 register (0x0Ch)) The parallel push button debounce settings (bits 5:4 of MIC_2 register (0x0Ch)) All register fields controlling the audio system should be defined before setting bit 1 of CHIP_MODE and should not be altered while the audio sub-system is active. If the analog or digital levels are below −12dB then it is not necessary to set the stereo bit allowing greater output levels to be obtained for such signals. 19 www.national.com LM49370 12.2 CLOCKS CONFIGURATION REGISTER This register is used to control the clocks throughout the chip. TABLE 3. CLOCKS (0x01h) Bits Field 1:0 DAC_CLK 7:2 R_DIV www.national.com Description This selects the clock to be used by the audio DAC system. DAC_CLK DAC Input Source 002 MCLK 002 PLL_OUTPUT 102 I2S_CLK_IN 112 PCM_CLK_IN This programs the R divider. R_DIV Divide Value 0 Bypass 1 Bypass 2 1.5 3 2 4 2.5 5 3 6 3.5 7 4 8 4.5 9 5 10 5.5 11 6 12 6.5 13 to 61 7 to 31 62 31.5 63 32 20 The audio ADC operates at 125*fs ( or 128*fs), so it requires a 1.000 MHz (or 1.024MHz) clock to sample at 8 kHz (at point C as marked on the following diagram). If the stereo DAC is running at 125*fs (or128*fs), it requires a 12.000MHz (or 12.288MHz) clock (at point B) for 48 kHz data. It is expected that the PLL is used to drive the audio system operating at 125*fs unless a 12.000 MHz master clock is supplied or the sample rate is always a multiple of 8 kHz. In this case the PLL can be bypassed to reduce power, with clock division being performed by the Q and R dividers instead. The PLL can also be bypassed if the system is running at 128*fs and a 12.288MHz master clock is supplied and the sample rate is a multiple of 8kHz. The PLL can also use the I2S clock input as a source. In this case, the audio DAC uses the clock from the output of the PLL and the audio ADC either uses the PLL output divided by 2*FS(DAC)/FS(ADC) or a system clock divided by Q, this allows n*8 kHz recording and 44.1 kHz playback. MCLK must be less than or equal to 30 MHz. I2S_CLK and PCM_CLK should be below 6.144MHz. When operating at 125*fs, the LM49370 is designed to work from a 12.000 MHz or 11.025 MHz clock at point A. When operating at 128*fs, the LM49370 is designed to work from a 12.288MHz or 11.2896 MHz clock at point A. This is used to drive the power management and control logic. Performance may not meet the electrical specifications if the frequency at this point deviates significantly beyond this range. 20191710 FIGURE 6. LM49370 Clock Network 21 www.national.com LM49370 12.3 LM49370 CLOCK NETWORK LM49370 12.4 COMMON CLOCK SETTINGS FOR THE DAC & ADC When DAC_MODE = '00' (bits 7:6 of (0x00h)), the DAC has an over sampling ratio of 125 but requires a 250*fs clock at point B. This allows a simple clocking solution as it will work from 12.000 MHz (common in most systems with Bluetooth or USB) at 48 kHz exactly, the following table describes the clock required at point B for various clock sample rates in the different DAC modes: TABLE 4. Common DAC Clock Frequencies DAC Sample Rate (kHz) Clock Required at B (OSR = 125) Clock Required at B (OSR = 128) 8 2 MHz 2.048 MHz 11.025 2.75625 MHz 2.8224 MHz 12 3 MHz 3.072 MHz 16 4 MHz 4.096 MHz 22.05 5.5125 MHz 5.6448 MHz 24 6 MHz 6.144 MHz 32 8 MHz 8.192 MHz 44.1 11.025 MHz 11.2896 MHz 48 12 MHz 12.288 MHz Note: When DAC_MODE = '01' with the I2S or PCM interface operating as master, the stereo DAC operates at half the frequency of the clock at point B. This divided by two DAC clock is used as the source clock for the audio port. The over sampling ratio of the ADC is set by ADC MODE (bit 0 of 0x07h)). The table below shows the required clock frequency at point C for the different ADC modes. TABLE 5. Common ADC Clock Frequencies ADC Sample Rate (kHz) Clock Required at C (OSR = 125) 8 1 MHz 1.024 MHz 11.025 1.378125 MHz 1.4112 MHz 12 1.5 MHz 1.536 MHz 16 2 MHz 2.048 MHz 22.05 2.75625 MHz 2.8224 MHz 24 3 MHz 3.072 MHz Methods for producing these clock frequencies are described in the PLL Section. www.national.com Clock Required at C (OSR = 128) 22 LM49370 12.5 PLL M DIVIDER CONFIGURATION REGISTER This register is used to control the input section of the PLL. (Note 12) TABLE 6. PLL_M (0x02h) Bits Field 0 RSVD 6:0 PLL_M 7 FORCERQ Description RESERVED PLL_M Input Divider Value 0 No Divided Clock 1 1 2 1.5 3 2 4 2.5 ... 3 to 63 126 63.5 127 64 If set, the R and Q divider are enabled and the DAC and ADC clocks are propagated. This allows operation of the I2S and PCM interfaces without the ADC or DAC being enabled, for example to act as a bridge or a clock master. The M divider should be set such that the output of the divider is between 0.5 MHz and 5 MHz. The division of the M divider is derived from PLL_M such that: M = (PLL_M + 1) / 2 Note 12: See Further Notes on PLL Programming for more detail. 23 www.national.com LM49370 12.6 PLL N DIVIDER CONFIGURATION REGISTER This register is used to control the feedback divider of the PLL. (Note 13) TABLE 7. PLL_N (0x03h) Bits Field 7:0 PLL_N Description This programs the PLL feedback divider as follows: PLL_N Feedback Divider Value 0 to 10 10 11 11 12 12 13 13 14 14 … … 249 249 250 to 255 250 The N divider should be set such that the output of the divider is between 0.5 MHz and 5 MHz. (Fin/M)*N will be the target resting VCO frequency, FVCO. The N divider should be set such that 40 MHz < (Fin/M)*N < 60 MHz. Fin/M is often referred to as Fcomp (comparison frequency) or Fref (reference frequency), in this document Fcomp is used. The integer division of the N divider is derived from PLL_N such that: For 9 < PLL_N < 251: N = PLL_N Note 13: See Further Notes on PLL Programming for further details. www.national.com 24 LM49370 12.7 PLL P DIVIDER CONFIGURATION REGISTER This register is used to control the output divider of the PLL. (Note 14) TABLE 8. PLL_P (0x04h) Bits Field 3:0 PLL_P 6:4 7 Q_DIV FAST_VCO Description This programs the PLL output divider as follows: PLL_P Output Divider Value 0 No Divided Clock 1 1 2 1.5 3 2 4 2.5 ... 3 to 7 14 7.5 15 8 This programs the Q Divider Q_DIV Divide Value 0002 2 0012 3 0102 4 0112 6 1002 8 1012 10 1102 12 1112 13 This programs the PLL VCO range: FAST_VCO PLL VCO Range 0 40 to 60MHz 1 60 to 80MHz The division of the P divider is derived from PLL_P such that: P = PLL_P + 1 Note 14: See Further Notes on PLL Programming for more details. 25 www.national.com LM49370 12.8 PLL N MODULUS CONFIGURATION REGISTER This register is used to control the modulation applied to the feedback divider of the PLL. (Note 15) TABLE 9. PLL_N_MOD (0x05h) Bits Field 4:0 PLL_N_MOD 6:5 PLL_CLK_SEL Description This programs the PLL N divider's fractional component: PLL_N_MOD Fractional Addition 0 0/32 1 1/32 2 to 30 2/32 to 30/32 31 31/32 This selects the clock to be used as input for the audio PLL. PLL_INPUT_CLK 7 RSVD 002 MCLK 012 I2S_CLK_IN 102 PCM_CLK_IN 112 — Reserved. The complete N divider is a fractional divider as such: N = PLL_N + PLL_N_MOD/32 If the modulus input is zero then the N divider is simply an integer N divider. The output from the PLL is determined by the following formula: Fout = (Fin*N)/(M*P) Note 15: See Further Notes on PLL Programming for more details. www.national.com 26 The sigma-delta PLL Is designed to drive audio circuits requiring accurate clock frequencies of up to 30MHz with frequency errors noise-shaped away from the audio band. The 5 bits of modulus control provide exact synchronization of 48kHz and 44.1kHz sample rates from any common system clock. In systems where an isochronous I2S data stream is the source of data to the DAC a clock synchronous to the sample rate should be used as input to the PLL (typically the I2S clock). If no isochronous source is available, then the PLL can be used to obtain a clock that is accurate to within 1Hz of the correct sample rate although this is highly unlikely to be a problem. 201917r0 FIGURE 7. PLL Overview TABLE 10. Example PLL Settings for 48 kHz and 44.1 kHz Sample Rates in DAC MODE 00 Fin (MHz) Fs (kHz) M N P PLL_M PLL_N PLL_N_MOD PLL_P Fout (MHz) 11 48 11 60 5 21 60 0 9 12 12.288 48 4 19.53125 5 7 19 17 9 12 13 48 13 60 5 25 60 0 9 12 14.4 48 9 37.5 5 17 37 16 9 12 16.2 48 27 100 5 53 100 0 9 12 16.8 48 14 50 5 27 50 0 9 12 19.2 48 13 40.625 5 25 40 20 9 12 19.44 48 27 100 6 53 100 0 11 12 19.68 48 20.5 62.5 5 40 62 16 9 12 19.8 48 16.5 50 5 32 50 0 9 12 11 44.1 11 55.125 5 21 55 4 9 11.025 11.2896 44.1 8 39.0625 5 15 39 2 9 11.025 12 44.1 5 22.96875 5 9 22 31 9 11.025 13 44.1 13 55.125 5 25 55 4 9 11.025 14.4 44.1 12 45.9375 5 23 45 30 9 11.025 16.2 44.1 9 30.625 5 17 9 20 9 11.025 16.8 44.1 17 55.78125 5 33 30 25 9 11.025 19.2 44.1 16 45.9375 5 31 45 30 9 11.025 19.44 44.1 13.5 38.28125 5 26 38 9 9 11.025 19.68 44.1 20.5 45.9375 44 40 45 30 7 11.025 19.8 44.1 11 30.625 5 21 30 20 9 11.025 27 www.national.com LM49370 12.9 FURTHER NOTES ON PLL PROGRAMMING LM49370 TABLE 11. Example PLL Settings for 48 kHz and 44.1 kHz Sample Rates in DAC MODE 01 Fin (MHz) Fs (kHz) M 12 48 12.5 13 48 26.5 14.4 48 37.5 16.2 48 16.8 48 19.2 48 19.44 19.68 N P PLL_M 64 5 24 112.71875 4.5 52 128 4 74 37.5 128 4.5 12.53 32 3.5 12.5 32 48 40.5 48 20.5 19.8 48 12 44.1 PLL_N PLL_N_MOD PLL_P Fout (MHz) 64 0 9 12.288 112 23 8 12.288 128 0 7 12.288 74 128 0 8 12.288 24 32 0 6 12.288 4 24 32 0 7 12.288 128 58 80 128 0 9 12.288 64 5 40 64 0 9 12.288 37.5 128 5.5 74 128 0 10 12.288 35.5 133.59375 4 70 133 19 7 11.2896 13 44.1 37 144.59375 4.5 73 144 19 8 11.2896 14.4 44.1 37.5 147 5 74 147 0 9 11.2896 16.2 44.1 47.5 182.0625 5.5 94 182 2 10 11.2896 16.8 44.1 12.5 42 5 24 42 0 9 11.2896 19.2 44.1 12.5 36.75 5 24 36 24 9 11.2896 19.44 44.1 37.5 98 4.5 74 98 0 9 11.2896 19.68 44.1 44.5 114.875 4.5 88 114 28 8 11.2896 19.8 44.1 48 136.84375 5 95 136 27 9 11.2896 www.national.com 28 An example of obtaining 12.000 MHz from 1.536 MHz is shown below (this is typical for deriving DAC clocks from I2S datastreams). Choose a small range of P so that the VCO frequency is swept between 40 MHz and 60 MHz (or 60–80 MHz if VCOFAST is used). Remembering that the P divider can divide by half integers, for a 12 MHz output, this gives possible P values of 3, 3.5, 4, 4.5, or 5. The M divider should be set such that the comparison frequency (Fcomp) is between 0.5 and 5 MHz. This gives possible M values of 1, 1.5, 2, 2.5, or 3. The most accurate N and N_MOD can be calculated by sweeping the P and M inputs of the following formulas: N = FLOOR(((Fout/Fin)*(P*M)),1) N_MOD = ROUND(32*((((Fout)/Fin)*(P*M)-N),0) This shows that setting M = 1, N = 39+1/16, P = 5 (i.e. PLL_M = 0, PLL_N = 39, PLL_N_MOD = 2, & PLL_P = 4) gives a comparison frequency of 1.536MHz, a VCO frequency of 60 MHz and an output frequency of 12.000 MHz. The same settings can be used to get 11.025 from 1.4112 MHz for 44.1 kHz sample rates. Care must be taken when synchronization of isochronous data is not possible, i.e. when the PLL has to be used but an exact frequency match cannot be found. The I2S should be master on the LM49370 so that the data source can support appropriate SRC as required. This method should only be used with data being read on demand to eliminate sample rate mismatch problems. Where a system clock exists at an integer multiple of the required ADC or DAC clock rate it is preferable to use this rather than the PLL. The LM49370 is designed to work in 8, 12, 16, 24, 48 kHz modes from a 12 MHz clock and 8 kHz modes from a 13 MHz clock without the use of the PLL. This saves power and reduces clock jitter which can affect SNR. 29 www.national.com LM49370 These tables cover the most common applications, obtaining clocks for derivative sample rates such as 22.05 kHz should be done by increasing the P divider value or using the R/Q dividers. LM49370 12.10 ADC_1 CONFIGURATION REGISTER This register is used to control the LM49370's audio ADC. TABLE 12. ADC_1 (0x06h) Bits Field 0 MIC_SELECT If set the microphone preamp output is added to the ADC input signal. 1 CPI_SELECT If set the cell phone input is added to the ADC input signal. 2 LEFT_SELECT 3 5:4 7:6 Description If set the left stereo bus is added to the ADC input signal. RIGHT_SELECT If set the right stereo bus is added to the ADC input signal. ADC_SAMPLE_ RATE HPF_MODE This programs the closest expected sample rate of the mono ADC, which is a variable required by the AGC algorithm whenever the AGC is in use. This does not set the sample rate of the mono ADC. ADC_SAMPLE_RATE Sample Rate 002 8 kHz 012 12 kHz 102 16 kHz 112 24 kHz This sets the HPF of the ADC HPF-MODE HPF Response 002 No HPF 012 FS = 8 kHz, −0.5 dB @ 300 Hz, Notch @ 55 Hz FS = 12 kHz, −0.5 dB @ 450 Hz, Notch @ 82 Hz FS = 16 kHz, −0.5 dB @ 600 Hz, Notch @ 110 Hz 102 FS = 8 kHz, −0.5 dB @ 150 Hz, Notch @ 27 Hz FS = 12 kHz, −0.5 dB @ 225 Hz, Notch @ 41 Hz FS = 16 kHz, −0.5 dB @ 300 Hz, Notch @ 55 Hz 112 www.national.com No HPF 30 LM49370 12.11 ADC_2 CONFIGURATION REGISTER This register is used to control the LM49370's audio ADC. TABLE 13. ADC_2 (0x07h) Bit s Field 0 ADC_MODE 1 ADC_MUTE Description This sets the oversampling ratio of the ADC MODE ADC OSR 0 125fs 1 128fs If set, the analog inputs to the ADC are muted. 4:2 AGC_FRAME_TIME This sets the frame time to be used by the AGC algorithm. In a given frame, the AGC's peak detector determines the peak value of the incoming microphone audio signal and compares this value to the target value of the AGC defined by AGC_TARGET (bits [3:1] of register (0x08h)) in order to adjust the microphone preamplifier's gain accordingly. AGC_FRAME_TIME basically sets the sample rate of the AGC to adjust for a wide variety of speech patterns. (Note 16) AGC_FRAME_TIME 6:5 ADC_CLK Time (ms) 0002 96 0012 128 0102 192 0112 256 1002 384 1012 512 1102 768 1112 1000 This selects the clock to be used by the audio ADC system. ADC_CLK 7 NGZXDD Source 002 MCLK 012 PLL_OUTPUT 102 I2S_CLK_IN 112 PCM_CLK_IN If set, the noise gate will not wait for a zero crossing before mute/unmuting. This bit should be set if the ADC's HPF is disabled and if there is a large DC or low frequency component at the ADC input. NGZXDD Result 0 Noise Gate operates on ZXD events 1 Noise Gate operates on frame boundaries Note 16: Refer to the AGC overview for further detail. 31 www.national.com LM49370 12.12 AGC_1 CONFIGURATION REGISTER This register is used to control the LM49370's Automatic Gain Control. (Note 17) TABLE 14. AGC_1 (0x08h) Bit s Field Description 0 AGC_ENABLE If set, the AGC controls the analog microphone preamplifier gain into the system. This feature is useful for microphone signals that are routed to the ADC. 3:1 AGC_TARGET This programs the target level of the AGC. This will depend on the expected transients and desired headroom. Refer to AGC_TIGHT (bit 7 of 0x09h) for more detail. 4 7:5 AGC_TARGET Target Level 0002 −6 dB 0012 −8 dB 0102 −10 dB 0112 −12 dB 1002 −14 dB 1012 −16 dB 1102 −18 dB 1112 −20 dB NOISE_GATE_ON If set, signals below the noise gate threshold are muted.The noise gate is only activated after a set period of signal absence. NOISE_ GATE_ THRES This field sets the expected background noise level relative to the peak signal level. The sole presence of signals below this level will not result in an AGC gain change of the input and will be gated from the ADC output if the NOISE_GATE_ON is set. This level must be set even if the noise gate is not in use as it is required by the AGC algorithm. NOISE_GATE_THRES Level 0002 −72 dB 0012 −66 dB 0102 −60 dB 0112 −54 dB 1002 −48 dB 1012 −42 dB 1102 −36 dB 1112 −30 dB Note 17: See the AGC overview. www.national.com 32 LM49370 12.13 AGC_2 CONFIGURATION REGISTER This register is used to control the LM49370's Automatic Gain Control. TABLE 15. AGC_2 (0x09h) Bits 3:0 6:4 7 Field Description AGC_MAX_GAIN This programs the maximum gain that the AGC algorithm can apply to the microphone preamplifier. AGC_DECAY AGC_TIGHT AGC_TIGHT = 0 AGC_TIGHT = 1 AGC_MAX_GAIN Max Preamplifier Gain 00002 6 dB 00012 8 dB 00102 10 dB 00112 12 dB 01002 to 11002 14 dB to 30 dB 11012 32 dB 11102 34 dB 11112 36 dB This programs the speed at which the AGC will increase gains if it detects the input level is a quiet signal. AGC_DECAY Step Time (ms) 0002 32 0012 64 0102 128 0112 256 1002 512 1012 1024 1102 2048 1112 4096 If set, the AGC algorithm controls the microphone preamplifier more exactly. (Note 18) AGC_TARGET Min Level Max Level 0002 −6 dB −3 dB 0012 −8 dB −4 dB 0102 −10 dB −5 dB 0112 −12 dB −6 dB 1002 −14 dB −7 dB 1012 −16 dB −8 dB 1102 −18 dB −9 dB 1112 −20 dB −10 dB 0002 −6 dB −3 dB 0012 −8 dB −5 dB 0102 −10 dB −7 dB 0112 −12 dB −9 dB 1002 −14 dB −11 dB 1012 −16 dB −13 dB 1102 −18 dB −15 dB 1112 −20 dB −17 dB Note 18: The AGC can be used to control the analog path of the microphone to the output stages or to optimize the microphone path for recording on the ADC. When the analog path is used this bit should be set to ensure the target is tightly adhered to. If the ADC is the only destination of the microphone or the desired analog mixer level is line level then AGC_TIGHT should be cleared, allowing greater dynamic rage of the recorded signal. For further details see the AGC overview. 33 www.national.com LM49370 12.14 AGC_3 CONFIGURATION REGISTER This register is used to control the LM49370's Automatic Gain Control. (Note 19) TABLE 16. AGC_3 (0x0Ah) Bits 4:0 7:5 Field Description AGC_HOLDTIME This programs the amount of delay before the AGC algorithm begins to adjust the gain of the microphone preamplifier. AGC_ATTACK AGC_HOLDTIME No. of speech segments 000002 0 000012 1 000102 2 000112 3 001002 to 111002 4 to 28 111012 29 111102 30 111112 31 This programs the speed at which the AGC will reduce gains if it detects the input level is too large. AGC_ATTACK Step Time (ms) 0002 32 0012 64 0102 128 0112 256 1002 512 1012 1024 1102 2048 1112 4096 Note 19: See the AGC overview. www.national.com 34 The Automatic Gain Control (AGC) system can be used to optimize the dynamic range of the ADC for voice data when the level of the source is unknown. A target level for the output is set so that any transients on the input won’t clip during normal operation. The AGC circuit then compares the output of the ADC to this level and increases or decreases the gain of the microphone preamplifier to compensate. If the audio from the microphone is to be output digitally through the ADC then the full dynamic range of the ADC can be used automatically. If the output is through the analog mixer then the ADC is used to monitor the microphone level. In this case, the analog dynamic range is less important than the absolute level, so AGC_TIGHT should be set to tie transients closely to the target level. To ensure that the system doesn’t reduce the quality of the speech by constantly modulating the microphone preamplifier gain, the ADC output is passed through an envelope detector. This frames the output of the ADC into time segments roughly equal to the phonemes found in speech (AGC_FRAME_TIME). To calculate this, the circuit must also know the sample rate of the data from the ADC (ADC_SAMPLERATE). If after a programmable number of these segments (AGC_HOLDTIME), the level is consistently below target, the gain will be increased at a programmable rate (AGC_DECAY). If the signal ever exceeds the target level (AGC_TARGET) then the gain of the microphone is reduced immediately at a programmable rate (AGC_ATTACK). This is demonstrated below: 20191712 AGC Operation Example The signal in the above example starts with a small analog input which, after the hold time has timed out, triggers a rise in the gain ((1) → (2)). After some time the real analog input increases and it reaches the threshold for a gain reduction which decreases the gain at a faster rate ((2) → (3)) to allow the elimination of typical popping noises. Only ADC outputs that are considered signal (rather than noise) are used to adjust the microphone preamplifier gain. The signal to noise ratio of the expected input signal is set by NOISE_GATE_THRESHOLD. In some situations it is preferable to remove audio considered to be consisting solely of background noise from the audio output; for example conference calls. This can be done by setting NOISE_GATE_ON. This does not affect the performance of the AGC algorithm. The AGC algorithm should not be used where very large background noise is present. If the type of input data, application and microphone is known then the AGC will typically not be required for good performance, it is intended for use with inputs with a large dynamic range or unknown nominal level. When setting NOISE_GATE_THRESHOLD be aware that in some mobile phone scenarios the ADC SNR will be dictated by the microphone performance rather than the ADC or the signal. Gain changes to the microphone are performed on zero crossings. To eliminate DC offsets, wind noise, and pop sounds from the output of the ADC, the ADC's HPF should always be enabled. 35 www.national.com LM49370 12.15 AGC OVERVIEW LM49370 12.16 MIC_1 CONFIGURATION REGISTER This register is used to control the microphone configuration. TABLE 17. MIC_1 (0x0Bh) Bits Field 3:0 PREAMP_GAIN 4 MIC_MUTE 5 INT_SE_DIFF 6 INT_EXT Description This programs the gain applied to the microphone preamplifier if the AGC is not in use. PREAMP_GAIN Gain 00002 6 dB 00012 8 dB 00102 10 dB 00112 12 dB 01002 to 11002 14 dB to 30 dB 11012 32 dB 11102 34 dB 11112 36 dB If set, the microphone preamplifier is muted. If set, the internal microphone is assumed to be single ended and the negative connection is connected to the ADC common mode point internally. This allows a single-ended internal microphone to be used. If set, the single ended external microphone is used and the negative microphone input is grounded internally, otherwise internal microphone operation is assumed. (Note 20) Note 20: On changing INT_EXT from internal to external note that the dc blocking cap will not be charged so some time should be taken (300 ms for a 1 µF cap) between the detection of an external headset and the switching of the output stages and ADC to that input to allow the DC points on either side of this cap to stabilize. This can be accomplished by deselecting the microphone input from the audio outputs and ADC until the DC points stabilize. An active MIC path to CPOUT or the ADC may result in the microphone DC blocking caps causing audio pops under the following situations: 1) Switching between internal and external microphone operation while in chip modes '10' or '11'. 2) Toggling in and out of powerdown/standby modes. 3) Toggling between chip modes '10' and '11' whenever external microphone operation is selected. 4) The insertion/removal of a headset while in chip modes '10' or '11' whenever external microphone operation is selected. To avoid these potential pop issues, it is recommended to deselect the microphone input from CPOUT and ADC until the DC points stabilize. www.national.com 36 LM49370 12.17 MIC_2 CONFIGURATION REGISTER This register is used to control the microphone configuration. TABLE 18. MIC_2 (0x0Ch) Bits Field 0 OCL_ VCM_ VOLTAGE 2:1 MIC_ BIAS_ VOLTAGE Description This selects the voltage used as virtual ground (HP_VMID pin) in OCL mode. This will depend on the available supply and the power output requirements of the headphone amplifiers. OCL_VCM_VOLTAGE Voltage 0 1.2V 1 1.5V This selects the voltage as a reference to the internal and external microphones. Only one bias pin is driven at once depending on the INT_EXT bit setting found in the MIC_1 (0x0Bh) register. MIC_BIAS_VOLTAGE should be set to '11' only if A_VDD > 3.4V. In OCL mode, MIC_BIAS_VOLTAGE = '00' (EXT_BIAS = 2.0V) should not be used to generate the EXT_BIAS supply for a cellular headset external microphone. Please refer to Table 19 for more detail. MIC_BIAS_VOLTAGE EXT_BIAS/INT_BIAS 002 2.0V 012 2.5V 102 2.8V 112 3.3V 3 BUTTON_TYPE If set, the LM49370 assumes that the button (if used) in the headset is in series (series push button) with the microphone, opening the circuit when pressed. The default is for the button to be in parallel (parallel push button), shorting out the microphone when pressed. 5:4 BUTTON_ DEBOUNCE_ TIME This sets the time used for debouncing the pushing of the button on a headset with a parallel push button. BUTTON_DEBOUNCE_TIME Time (ms) 002 0 012 8 102 16 112 32 In OCL mode there is a trade-off between the external microphone supply voltage (EXT_MIC_BIAS - OCL_VCM_ VOLTAGE) and the maximum output power possible from the headphones. A lower OCL_VCM_VOLTAGE gives a higher microphone supply voltage but a lower maximum output power from the headphone amplifiers due to the lower OCL_VCM_VOLTAGE - A_VSS. TABLE 19. External MIC Supply Voltages in OCL Mode Available A_VDD Recommended EXT_MIC_BIAS Supply to Microphone OCL_VCM_VOLT = 1.5V OCL_VCM_VOLT = 1.2V > 3.4V 3.3V 1.8V 2.1V 2.9V to 3.4V 2.8V 1.3V 1.6V 2.8V to 2.9V 2.5V 1.0V 1.3V 2.7V to 2.8V 2.5V - 1.3V 37 www.national.com LM49370 12.18 SIDETONE ATTENUATION REGISTER This register is used to control the analog sidetone attenuation. (Note 21) TABLE 20. SIDETONE (0x0Dh) Bits Field 3:0 SIDETONE_ ATTEN Description This programs the attenuation applied to the microphone preamp output to produce a sidetone signal. SIDETONE_ATTEN Attenuation 00002 -Inf 00012 −30 dB 00102 −27 dB 00112 −24 dB 01002 −21 dB 01012 to 10102 −18 dB to −3 dB 10112 to 11112 0 dB Note 21: An active SIDETONE path to an audio output may result in the microphone DC blocking caps causing audio pops under the following situations: 1) Switching between internal and external microphone operation while in chip modes '10' or '11'. 2) Toggling in and out of powerdown/standby modes. 3) Toggling between chip modes '10' and '11' whenever external microphone operation is selected. 4) The insertion/removal of a headset while in chip modes '10' or '11' whenever external microphone operation is selected. To avoid potential pop noises, it is recommended to set SIDETONE_ATTEN to '0000' until DC points have stabilized whenever the SIDETONE path is used. 12.19 CP_INPUT CONFIGURATION REGISTER This register is used to control the differential cell phone input. TABLE 21. CP_INPUT (0x0Eh) Bits Field 4:0 CPI_LEVEL 5 CPI_MUTE www.national.com Description This programs the gain/attenuation applied to the cell phone input. CPI_LEVEL Level 000002 −34.5 dB 000012 −33 dB 000102 −31.5 dB 000112 −30 dB 00100 to 111002 −28.5 dB to +7.5 dB 111012 +9 dB 111102 +10.5 dB 111112 +12 dB If set, the CPI input is muted at source. 38 LM49370 12.20 AUX_LEFT CONFIGURATION REGISTER This register is used to control the left aux analog input. TABLE 22. AUX_LEFT (0x0Fh) Bits Field 4:0 AUX_ LEFT_ LEVEL 5 6 7 AUX_ LEFT_ BOOST AUX_L_MUTE Description This programs the gain/attenuation applied to the AUX LEFT analog input to the mixer. (Note 22) AUX_LEFT_LEVEL Level (With Boost) Level (Without Boost) 000002 −34.5 dB −46.5 dB 000012 −33 dB −45 dB 000102 −31.5 dB −43.5 dB 000112 −30 dB −42 dB 00100 to 111002 −28.5 dB to +7.5 dB −40.5 dB to −4.5 dB 111012 +9 dB −3 dB 111102 +10.5 dB −1.5 dB 111112 +12 dB 0 dB If set, the gain of the AUX_LEFT input to the mixer is increased by 12 dB (see above). If set, the AUX LEFT input is muted. AUX_OR_DAC_L If set, the AUX LEFT input is passed to the mixer, the default is for the DAC LEFT output to be passed to the mixer. Note 22: The recommended mixer level is 1V RMS. The auxiliary analog inputs can be boosted by 12 dB if enough headroom is available. Clipping may occur if the analog power supply is insufficient to cater for the required gain. 12.21 AUX_RIGHT CONFIGURATION REGISTER This register is used to control the right aux analog input. TABLE 23. AUX_RIGHT (0x10h) Bits Field 4:0 AUX_ RIGHT_ LEVEL Description This programs the gain/attenuation applied to the AUX RIGHT analog input to the mixer. (Note 23) AUX_RIGHT_LEVEL Level (With Boost) Level (Without Boost) 000002 −34.5 dB −46.5 dB 000012 −33 dB −45 dB 000102 −31.5 dB −43.5 dB 000112 −30 dB −42 dB 00100 to 111002 −28.5 dB to +7.5 dB −40.5 dB to −4.5 dB 111012 +9 dB −3 dB 111102 +10.5 dB −1.5 dB 111112 +12 dB 0 dB 5 AUX_ RIGHT_BOOST If set, the gain of the AUX_RIGHT input to the mixer is increased by 12 dB (see above). 6 AUX_R_MUTE If set, the AUX RIGHT input is muted. 7 AUX_OR_DAC_R If set, the AUX RIGHT input is passed to the mixer, the default is for the DAC RIGHT output to be passed to the mixer. Note 23: The recommended mixer level is 1V RMS. The auxiliary analog inputs can be boosted by 12 dB if enough headroom is available. Clipping may occur if the analog power supply is insufficient to cater for the required gain. 39 www.national.com LM49370 12.22 DAC CONFIGURATION REGISTER This register is used to control the DAC levels to the mixer. TABLE 24. DAC (0x11h) Bits Field 4:0 DAC_LEVEL Description This programs the gain/attenuation applied to the DAC input to the mixer. (Note 24) DAC_LEVEL Level (With Boost) Level (Without Boost) 000002 −34.5 dB −46.5 dB 000012 −33 dB −45 dB 000102 −31.5 dB −43.5 dB 000112 −30 dB −42 dB 00100 to 111002 −28.5 dB to +7.5 dB −40.5 dB to −4.5 dB 111012 +9 dB −3 dB 111102 +10.5 dB −1.5 dB 111112 +12 dB 0 dB 5 DAC_BOOST If set, the gain of the DAC inputs to the mixer is increased by 12dB (see above). 6 DAC_MUTE If set, the stereo DAC input is muted on the next zero crossing. 7 USE_AUX_ LEVELS If set, the gain of the DAC inputs is controlled by the AUX_LEFT and AUX_RIGHT registers, allowing a stereo balance to be applied. Note 24: The output from the DAC is 1V RMS for a full scale digital input. This can be boosted by 12 dB if enough headroom is available. Clipping may occur if the analog power supply is insufficient to cater for the required gain. www.national.com 40 LM49370 12.23 CP_OUTPUT CONFIGURATION REGISTER This register is used to control the differential cell phone output. (Note 25) TABLE 25. CP_OUTPUT (0x12h) Bit s Field 0 MIC_SELECT 1 RIGHT_SELECT 2 LEFT_SELECT 3 CPO_MUTE 4 Description If set, the microphone channel of the mixer is added to the CP_OUT output signal. If set, the right channel of the mixer is added to the CP_OUT output signal. If set, the left channel of the mixer is added to the CP_OUT output signal. If set, the CPOUT output is muted. MIC_NOISE_GAT If this is set and NOISE_GATE_ON (register 0x08h) is enabled, the MIC to CPO path will be gated if the E signal is determined to be noise by the AGC (that is, if the signal is below the set noise threshold). Note 25: The gain of cell phone output amplifier is 0 dB. 12.24 AUX_OUTPUT CONFIGURATION REGISTER This register is used to control the differential auxiliary output. (Note 26) TABLE 26. AUX_OUTPUT (0x13h) Bits 0 1 Field CPI_SELECT Description If set, the cell phone input channel of the mixer is added to the AUX_OUT output signal. RIGHT_SELECT If set, the right channel of the mixer is added to the AUX_OUT output signal. 2 LEFT_SELECT 3 AUX_MUTE If set, the left channel of the mixer is added to the AUX_OUT output signal. If set, the AUX_OUT output is muted. Note 26: The gain of the auxiliary output amplifier is 0 dB. If a second (external) loudspeaker amplifier is to be used its gain should be set to 12 dB to match the onboard loudspeaker amplifier gain. 12.25 LS_OUTPUT CONFIGURATION REGISTER This register is used to control the loudspeaker output. (Note 27) TABLE 27. LS_OUTPUT (0x14h) Bits 0 1 Field CPI_SELECT Description If set, the cell phone input channel of the mixer is added to the loudspeaker output signal. RIGHT_SELECT If set, the right channel of the mixer is added to the loudspeaker output signal. 2 LEFT_SELECT 3 LS_MUTE 4 RSVD If set, the left channel of the mixer is added to the loudspeaker output signal. If set, the loudspeaker output is muted. Reserved. Note 27: The gain of the loudspeaker output amplifier is 12 dB. 41 www.national.com LM49370 12.26 HP_OUTPUT CONFIGURATION REGISTER This register is used to control the stereo headphone output. (Note 28) TABLE 28. HP_OUTPUT (0x15h) Bits 0 Field Description SIDETONE_SELECT If set, the sidetone channel of the mixer is added to both of the headphone output signals. 1 CPI_SELECT 2 RIGHT_SELECT If set, the cell phone input channel of the mixer is added to both of the headphone output signals. If set, the right channel of the mixer is added to the headphone output. If the STEREO bit (0x00h) is set, the right channel is added to the right headphone output signal only. If the STEREO bit (0x00h) is cleared, it is added to both the right and left headphone output signals. 3 LEFT_SELECT If set, the left channel of the mixer is added to the headphone output. If the STEREO bit (0x00h) is set, the left channel is added to the left headphone output signal only. If the STEREO bit (0x00h) is cleared, it is added to both the right and left headphone output signals. 4 HP_MUTE 5 STEREO 6 OCL If set, the headphone output is muted. If set, the mixers assume that the signals on the left and right internal busses are highly correlated and when these signals are combined their levels are reduced by 6dB to allow enough headroom for them to be summed. If set, the part is placed in OCL (Output Capacitor Less) mode. Note 28: The gain of the headphone output amplifier is –6 dB for the cell phone input channel and sidetone channel of the mixer. When the STEREO bit (0x00h) is set, headphone output amplifier gain is –6 dB for the left and right channel. When the STEREO bit (0x00h) is cleared, the headphone output amplifier gain is –12 dB for the left and right channel (to allow enough headroom for adding them and routing them to both headphone amplifiers). 12.27 EP_OUTPUT CONFIGURATION REGISTER This register is used to control the mono earpiece output. (Note 29) TABLE 29. EP_OUTPUT (0x16h) Bits 0 Field Description SIDETONE_SELECT If set, the sidetone channel of the mixer is added to the earpiece output signal. 1 CPI_SELECT 2 RIGHT_SELECT 3 LEFT_SELECT 4 EP_MUTE If set, the cell phone input channel of the mixer is added to the earpiece output signal. If set, the right channel of the mixer is added to the earpiece output signal. If set, the left channel of the mixer is added to the earpiece output signal. If set, the earpiece output is muted. Note 29: The gain of the earpiece output amplifier is 6 dB. www.national.com 42 LM49370 12.28 DETECT CONFIGURATION REGISTER This register is used to control the headset detection system. TABLE 30. DETECT (0x17h) Bits Field Description 0 DET_INT If set, an IRQ is raised when a change is detected in the headset status. Clearing this bit will clear an IRQ that has been triggered by the headset detect. 1 BTN_INT If set, an IRQ is raised when the headset button is pressed. Clearing this bit will clear an IRQ that has been triggered by a button event. 2 TEMP_INT If set, an IRQ is raised during a temperature event. The LM49370 will still automatically cycle the class AB power amplifiers off if the internal temperature is too high. This bit should not be set whenever the class D amplifier is turned on. Clearing this bit will clear an IRQ that has been triggered by a temperature event. 6:3 HS_ DBNC_TIME This sets the time used for debouncing the analog signals from the detection inputs used to sense the insertion/removal of a headset. HS_DBNC_TIME Time (ms) 00002 0 00012 8 00102 16 00112 32 01002 48 01012 64 01102 96 01112 128 10002 192 10012 256 10102 384 10112 512 11002 768 11012 1024 11102 1536 11112 2048 43 www.national.com LM49370 12.29 HEADSET DETECT OVERVIEW The LM49370 has built in monitors to automatically detect headset insertion or removal. The detection scheme can differentiate between mono, stereo, mono-cellular and stereo-cellular headsets. Upon detection of headset insertion or removal, the LM49370 updates read-only bit 0 - headset absence/presence, bit 1- mono/stereo headset and bit 2 - headset without mic / with mic, of the STATUS register (0x18h). Headset insertion/removal and headset type can also be detected in standby mode; this consumes no analog supply current when the headset is absent. The LM49370 can be programmed to raise an interrupt (set the IRQ pin high) when headset insert/removal is sensed by setting bit 0 of DETECT (0x17h). When headset detection is enabled in active mode and a headset is not detected, the HPL_OUT and HPR_OUT amplifiers will be disabled (switched off for capless mode and muted for AC-coupled mode) and the EXT_BIAS pin will be disconnected from the MIC_BIAS amplifier, irrespective of control register settings. The LM49370 also has the capability to detect button press, when a button is present on the headset microphone. Both parallel button-type (in parallel with the headset microphone, default value) and series button-type (in series with the headset microphone) can be detected; the button type used needs to be defined in bit 3 of MIC_2 (0x0Ch). Button press can also be detected in standby mode; this consumes 10 µA of analog supply current for a series type push button and 100 µA for a parallel type push button. Upon button press, the LM49370 updates bit 3 of STATUS (0x18h). In active OCL mode, with internal microphone selected (INT_EXT = 0; (reg 0x0Bh)), if a parallel pushbutton headset is inserted into the system, INT_EXT must be set high before BTN (bit 3 of STATUS (0x18h)) can be read. The LM49370 can also be programmed to raise an interrupt on the IRQ pin when button press is sensed by setting bit 1 of DETECT (0x17h). The LM49370 provides debounce programmability for headset and button detect. Debounce programmability can be used to reject glitches generated, and hence avoid false detection, while inserting/removing a headset or pressing a button. Headset insert/removal debounce time is defined by HS_DBNC_TIME; bits 6:3 of DETECT (0x17h). Parallel button press debounce time is defined by BTN_DBNC_TIME; bits 5:4 of MIC_2 (0x0Ch). Note that since the first effect of a series button press (microphone disconnected) is indistinguishable from headset removal, the debounce time for series button press in defined by HS_DBNC_TIME. Headset and push button detection can be enabled by setting CHIP_MODE 0; bit 0 of BASIC (0x00h). For reliable headset / push button detection all following bits should be defined before enabling the headset detection system: 1) the OCL-bit (AC-Coupled / Capless headphone interface (bit 6 of HP_OUTPUT (0x15h)) 2) the headset insert/removal debounce settings (bit 6:3 of DETECT (0x17h)) 3) the BTN_TYPE-bit (Parallel / Series push button type (bit 3 of MIC_2 (0x0Ch)) 4) the parallel push button debounce settings (bit 5:4 of MIC_2 (0x0Ch)) Figure 8 shows terminal connections and jack configuration for various headsets. Care should be taken to avoid any DC path from the MIC_DET pin to ground when a headset is not inserted. www.national.com 44 LM49370 20191713 FIGURE 8. Headset Configurations Supported by the LM49370 The wiring of the headset jack to the LM49370 will depend on the intended mode of the headphone amplifier: 45 www.national.com LM49370 20191714 FIGURE 9. Connection of Headset Jack to LM49370 Depends on the Mode of the Headphone Amplifier. www.national.com 46 LM49370 12.30 STATUS REGISTER This register is used to report the status of the device. TABLE 31. STATUS (0x18h) Bits Field Description 0 HEADSET This field is high when headset presence is detected (only valid if the detection system is enabled). (Note 30) 1 STEREO_ HEADSET This field is high when a headset with stereo speakers is detected (only valid if the detection system is enabled). (Note 30) 2 MIC This field is high when a headset with a microphone is detected (only valid if the detection system is enabled). (Note 30) 3 BTN This field is high when the button on the headset is pressed (only valid if the detection system is enabled). IRQ is cleared when the button has been released and this register has been written to. (Note 31) 4 TEMP If this field is high then a temperature event has occurred (write to this register to clear IRQ). This field will stay high even when the IRQ is cleared so long as the event occurs. This bit is only valid whenever the loudspeaker amplifier is turned off. (Note 31) 5 GPIN1 When GPIO_SEL is set to a readable configuration a digital input on GPIO1 can be read back here. 6 GPIN2 When GPIO_SEL is set to a readable configuration, a digital input on the relevant GPIO can be read back here. Note 30: The detection IRQ is cleared when this register has been written to. Note 31: This field is cleared whenever the STATUS (0x18h) register has been written to. 47 www.national.com LM49370 12.31 3D CONFIGURATION REGISTER This register is used to control the configuration of the 3D circuit. TABLE 32. 3D (0x19h) Bits Field Description 0 3D_ENB Setting this bit enables the 3D effect. When cleared to zero, the 3D effect is disabled and the 3D module then passes the I2S left and right channel inputs to the DAC unchanged. The stereo AUX inputs are unaffected by the 3D module. 1 3D_TYPE This bit selects between type 1 and type 2 3D sound effect. Clearing this bit to zero selects type 1 effect and setting it to one selects type 2. Type1: Rout = Ri-G*Lout3d, Lout = Li-G*Rout3d Type2: Rout = -Ri-G*Lout3d, Lout = Li+G*Rout3d where, Ri = Right I2S channel input Li = Left I2S channel input G = 3D gain level (Mix ratio) Rout3d = Ri filtered through a high-pass filter with a corner frequency controlled by FREQ Lout3d = Li filtered through a high-pass filter with a corner frequency controlled by FREQ 3:2 LEVEL This programs the level of 3D effect that is applied. LEVEL 5:4 FREQ 002 25% 012 37.5% 102 50% 112 75% This programs the HPF rolloff (-3dB) frequency of the 3D effect. FREQ 002 0Hz 012 300Hz 102 600Hz 112 900Hz 6 ATTENUATE Clearing this bit to zero maintains the level of the left and right input channels at the output. Setting this bit to one attenuates the output level by 50%. This may be appropriate for high level audio inputs when type 2 3D effect is used. Type 2 effect involves adding the same polarity of left and right inputs to give the final outputs. Type 2 effect has the potential for creating a clipping condition, however this bit offers an alternative to clipping. 7 CUST_COMP If set, the DAC compensation filter may be programmed by the user through registers (0x20h) to( 0x25h). Otherwise, the defaults are used. www.national.com 48 LM49370 12.32 I2S PORT MODE CONFIGURATION REGISTER This register is used to control the audio data interfaces. TABLE 33. I2S Mode (0x1Ah) Bits Field 0 I2S_OUT_ENB 1 I2S_IN_ENB 2 I2S_MODE Description If set, the gated. I2S output bus is enabled. If cleared, the I2S output will be tristate and all RX clocks will be If set, the I2S input is enabled. If this bit cleared, the I2S input is ignored and all TX clocks gated. This programs the format of the I2S interface. Definition 3 0 Normal 1 Left Justified I2S_STEREO_REVERSE If set, the left and right channels are reversed. Operation 4 I2S_WS_MS 6:5 I2S_WS_GEN_MODE 0 Normal 1 Reversed If set, I2S_WS generation is enabled and is Master. If cleared, I2S_WS acts as slave. This programs the I2S word length. Bits/Word 7 I2S_WORD_ORDER 002 16 012 25 102 32 112 — This bit alters the RX phasing of left and right channels. If this bit is cleared: right then left. If this bit is set: left then right. 201917r4 I2S Audio Port CLOCK/SYNC Options 49 www.national.com LM49370 12.33 I2S PORT CLOCK CONFIGURATION REGISTER This register is used to control the audio data interfaces. TABLE 34. I2S Clock (0x1Bh) Bit s Field 0 I2S_CLOCK_MS 1 I2S_CLOCK_SOURCE Description If set, then I2S clock generation is enabled and is Master. If this bit is cleared, then the I2S clock is driven by the device slave. This selects the source of the clock to be used by the I2S clock generator. I2S_CLOCK_SOURCE Clock is source from 0 DAC (from R divider) 1 ADC (from Q divider) 5:2 I2S_CLOCK_GEN_MODE This programs a clock divider that divides the clock defined by I2S_CLOCK_SOURCE. This divided clock is used to generate I2S_CLK in Master mode. (Note 32) 7:6 PCM_SYNC_WIDTH Value Divide By 00002 1 00012 2 00102 4 00112 6 01002 8 01012 10 01102 16 Ratio 01112 20 — 10002 2.5 2/5 10012 3 1/3 10102 3.90625 32/125 10112 5 25/125 11002 7.8125 16/125 11012 — — 11102 — — 11112 — — This programs the width of the PCM sync signal. Generated SYNC Looks like: 002 1 bit (Used for Short PCM Modes) 012 4 bits (Used for Long PCM Modes) 102 8 bits (Used for Long PCM Modes) 112 15 bits (Used for Long PCM Modes) Should not be set if the bits/word is less than 16. Note 32: For DAC_MODE = '00', '10', '11', DAC_CLOCK is the clock at the output of the R divider. For DAC_MODE = '01', DAC_CLOCK is a divided by two version of the clock at the output of the R divider. www.national.com 50 I2S master mode can only be used when the DAC is enabled unless the FORCE_RQ bit is set. PCM Master mode can only be used when the ADC is enabled, unless the FORCE_RQ bit is set. If the PCM receiver interface is operated in slave mode the clock and sync should be enabled at the same time because the PCM receiver uses the first PCM frame to calculate the PCM interface format. This format can not be changed unless a soft reset is issued. Operating the LM49370 in master mode eliminates the risk of sample rate mismatch between the data converters and the audio interfaces. In slave mode, the PCM and I2S receivers only record the 1st 16 and 18 bits of the serial words respectively. The I2S and PCM formats are as followed: 20191715 FIGURE 10. I2S Serial Data Format (Default Mode) 201917q8 FIGURE 11. I2S Serial Data Format (Left Justified) 20191716 FIGURE 12. PCM Serial Data Format (16 bit Slave Example) 51 www.national.com LM49370 12.34 DIGITAL AUDIO DATA FORMATS LM49370 12.35 PCM PORT MODE CONFIGURATION REGISTER This register is used to control the audio data interfaces. TABLE 35. PCM MODE (0x1Ch) Bits Field 0 PCM_OUT_ENB If set, the PCM output bus is enabled. If this bit is cleared, thr PCM output will be tristate and all RX clocks will be gated. 1 PCM_IN_ENB If set, the PCM input is enabled. If this bit is cleared, the PCM input is ignored and TX clocks are generated. 3 PCM_CLOCK_SOURCE DAC or ADC Clock 0 = DAC, 1 = ADC (Note 32) 4 PCM_SYNC_MS 5 PCM_SDO_LSB_HZ 6 PCM_COMPAND 7 Description PCM_ALAW_μLAW If set, PCM_SYNC generation is enabled and is driven by the device (Master). If set, when the PCM port has run out of bits to transmit, it will tristate the SDO output. If set, the data sent to the PCM port is companded and the PCM data received by the PCM receiver is treated as companded data. If PCM_ COMPAND is set, then the data across the PCM interface to the DAC and from the ADC is companded as follows: PCM_ALAW_μLAW Commanding Type 0 μ-LAW 1 A-Law 201917r1 FIGURE 13. PCM Audio Port CLOCK/SYNC Options www.national.com 52 LM49370 12.36 PCM PORT CLOCK CONFIGURATION REGISTER This register is used to control the configuration of audio data interfaces. TABLE 36. PCM Clock (0x1Dh) Bits Field 3:0 PCM_CLOCK_ GEN_MODE 6:4 PCM_SYNC_MODE Description This programs a clock divider that divides the clock defined by PCM_CLOCK_SOURCE reg (0x1Ch). The divided clock is used to generate PCM_CLK in Master mode. (Note 32) Value Divide By 00002 1 00012 2 00102 4 00112 6 Ratio 01002 8 01012 10 01102 16 01112 20 — 10002 2.5 2/5 10012 3 1/3 10102 3.90625 32/125 10112 5 25/125 11002 7.8125 16/125 11012 — — 11102 — — 11112 — — This programs a clock divider that divides PCM_CLK. The divided clock is used to generate PCM_SYNC. Valve Divide By 0002 8 0012 16 0102 25 0112 32 1002 64 1012 128 1102 — 1112 — 53 www.national.com LM49370 12.37 SRC CONFIGURATION REGISTER This register is used to control the configuration of the Digital Routing interfaces. (Note 33) TABLE 37. Bridges (0x1Eh) Bits Field 0 PCM_TX_SEL Description This controls the data sent to the PCM transmitter. PCM_TX_SEL 2:1 I2S_TX_SEL Source 0 ADC 1 MONO SUM Circuit This controls the data sent to the I2S transmitter. I2S_TX_SEL 4:3 DAC_INPUT_SEL Source 002 ADC 012 PCM Receiver 102 DAC Interpolator (oversampled) 112 Disabled This controls the data sent to the DAC. DAC_INPUT_SEL 5 7:6 MONO_SUM_SEL MONO_SUM_MODE Source 002 I2S Receiver (In stereo) 012 PCM Receiver (Dual Mono) 102 ADC 112 Disabled This controls the data sent to the Stereo to Mono Converter MONO_SUM_SEL Source 0 DAC Interpolated Output 1 I2S Receiver Output This controls the operation of the Stereo to Mono Converter. MONO_SUM_ MODE Operation 002 (Left + Right)/2 012 Left 102 Right 112 (Left + Right)/2 Note 33: Please refer to the Application Note AN-1591 for the detailed discussion on how to use the I2S to PCM Bridge. www.national.com 54 LM49370 201917r2 FIGURE 14. I2S to PCM Bridge 55 www.national.com LM49370 12.38 GPIO CONFIGURATION REGISTER This register is used to control the GPIOs and to control the digital signal routing when using the ADC and DAC to perform sample rate conversion. TABLE 38. GPIO Control (0x1Fh) Bits Field 2:0 GPIO_1_SEL Description This configures the GPIO_1 pin. GPIO_1_SEL 5:3 GPIO_2_SEL Does What? Direction 0002 Disable HiZ 0012 SPI_SDO Output 0102 Output 0 Output 0112 Output 1 Output 1002 Read Input 1012 Class D Enable Output 1102 AUX Enable Output 1112 Dig_Mic_Data Input GPIO_2_SEL Does What? Direction 0002 Disable HiZ 0012 SPI_SDO Output 0102 Output 0 Output 0112 Output 1 Output 1002 Read Input 1012 Class D Enable Output 1102 Dig_Mic L Clock Output 1112 Dig_Mic R Clock Output This configures the GPIO_2 pin. 6 ADC_SRC_MODE If set, the ADC analog is disabled and the digital is enabled, using the resampler input. 7 DAC_SRC_MODE This does not have to be set to use DAC in SRC mode, but should be set if the user wishes to disable the DAC analog to save power. 12.39 DAC PATH COMPENSATION FIR CONFIGURATION REGISTERS To allow for compensation of roll off in the DAC and analog filter sections an FIR compensation filter is applied to the DAC input data at the original sample rate. Since the DAC can operate at different over sampling ratios the FIR compensation filter is programmable. By default the filter applies approx 2dB of compensation at 20kHz. 5 taps is sufficient to allow passband equalization and ripple cancellation to around +/0.01dB. The filter can also be used for precise digital gain and simple tone controls although a DSP or CPU should be used for more powerful tone control if required. As the FIR filter must always be phase linear, the coefficients are symmetrical. Coefficients C0, C1, and C2 are programmable, C3 is equal to C1 and C4 is equal to C0. The maximum power of this filter must not exceed that of the examples given below: www.national.com 56 LM49370 201917r3 FIGURE 15. FIR Consumption Filter Taps Sample Rate DAC_MODE C0 C1 C2 C3 C4 48kHz 00 334 –2291 26984 –2291 343 48kHz 01 61 –371 25699 –371 61 For DAC_MODE = '00 and '01', the defaults should be sufficient; but for DAC_MODE = '10' and '11', care should be taken to ensure the widest bandwidth is available without requiring such a large attenuation at DC that inband noise becomes audible. TABLE 39. Compensation Filter C0 LSBs (0x20h) Bits Field 7:0 C0_LSB Description Bits 7:0 of C0[15:0] TABLE 40. Compensation Filter C0 MSBs (0x21h) Bits Field 7:0 C0_MSB Description Bits 15:8 of C0[15:0] TABLE 41. Compensation Filter C1 LSBs (0x22h) Bits Field 7:0 C1_LSB Description Bits 7:0 of C1[15:0] TABLE 42. Compensation Filter C1 MSBs (0x23h) Bits Field 7:0 C1_MSB Description Bits 15:8 of C1[15:0] TABLE 43. Compensation Filter C2 LSBs (0x24h) Bits Field 7:0 C2_LSB Description Bits 7:0 of C2[15:0] TABLE 44. Compensation Filter C2 MSBs (0x25h) Bits Field 7:0 C2_MSB Description Bits 15:8 of C2[15:0] 57 www.national.com LM49370 13.0 Typical Performance Characteristics (For all performance curves AVDD refers to the voltage applied to the A_VDD and LS_VDD pins. DVDD refers to the voltage applied to the D_VDD and PLL_VDD pins; AVDD = 3.3V and DVDD = 3.3V unless otherwise specified. Stereo DAC Frequency Response fS = 8kHz Stereo DAC Frequency Response Zoom fS = 8kHz 20191701 20191702 Stereo DAC Frequency Response fS = 16kHz Stereo DAC Frequency Response Zoom fS = 16kHz 20191703 20191704 Stereo DAC Frequency Response fS = 24kHz Stereo DAC Frequency Response Zoom fS = 24kHz 20191705 www.national.com 20191708 58 Stereo DAC Frequency Response Zoom fS = 32kHz 20191711 20191717 Stereo DAC Frequency Response fS = 48kHz Stereo DAC Frequency Response Zoom fS = 48kHz 20191719 20191718 THD+N vs Stereo DAC Input Voltage (0dB DAC, AUXOUT) Stereo DAC Crosstalk (0dB DAC, HP SE) 20191721 20191720 59 www.national.com LM49370 Stereo DAC Frequency Response fS = 32kHz LM49370 MONO ADC Frequency Response fS = 8kHz, 6dB MIC MONO ADC Frequency Response Zoom fS = 8kHz, 6dB MIC 20191722 20191725 MONO ADC Frequency Response fS = 8kHz, 36dB MIC MONO ADC Frequency Response Zoom fS = 8kHz, 36dB MIC 20191726 20191727 MONO ADC Frequency Response fS = 16kHz, 6dB MIC MONO ADC Frequency Response Zoom fS = 16kHz, 6dB MIC 20191728 www.national.com 20191729 60 MONO ADC Frequency Response Zoom fS = 16kHz, 36dB MIC 20191747 20191748 MONO ADC Frequency Response fS = 24kHz, 6dB MIC MONO ADC Frequency Response Zoom fS = 24kHz, 6dB MIC 20191749 20191750 MONO ADC Frequency Response fS = 24kHz, 36dB MIC MONO ADC Frequency Response Zoom fS = 24kHz, 36dB MIC 20191751 20191752 61 www.national.com LM49370 MONO ADC Frequency Response fS = 16kHz, 36dB MIC LM49370 MONO ADC Frequency Response fS = 32kHz, 6dB MIC MONO ADC Frequency Response Zoom fS = 32kHz, 6dB MIC 20191753 20191754 MONO ADC Frequency Response fS = 32kHz, 36dB MIC MONO ADC Frequency Response Zoom fS = 32kHz, 36dB MIC 20191755 20191756 MONO ADC HPF Frequency Response fS = 8kHz, 36dB MIC (from left to right: HPF_MODE '00', '10', '01') MONO ADC HPF Frequency Response fS = 16kHz, 36dB MIC (from left to right: HPF_MODE '00', '10', '01') 20191757 www.national.com 20191758 62 MONO ADC HPF Frequency Response fS = 32kHz, 36dB MIC (from left to right: HPF_MODE '00', '10', '01') 20191759 20191760 MONO ADC THD+N vs MIC Input Voltage (fS = 8kHz, 6dB MIC) MONO ADC THD+N vs MIC Input Voltage (fS = 8kHz, 36dB MIC) 20191762 20191761 MONO ADC PSRR vs Frequency AVDD = 3.3V, 6dB MIC MONO ADC PSRR vs Frequency AVDD = 5V, 6dB MIC 20191763 20191764 63 www.national.com LM49370 MONO ADC HPF Frequency Response fS = 24kHz, 36dB MIC (from left to right: HPF_MODE '00', '10', '01') LM49370 MONO ADC PSRR vs Frequency AVDD = 3.3V, 36dB MIC MONO ADC PSRR vs Frequency AVDD = 5V, 36dB MIC 20191765 20191766 AUXOUT PSRR vs Frequency AVDD = 3.3V, 0dB AUX (AUX inputs terminated) AUXOUT PSRR vs Frequency AVDD = 5V, 0dB AUX (AUX inputs terminated) 20191767 20191768 AUXOUT PSRR vs Frequency AVDD = 3.3V, 0dB CPI (CPI inputs terminated) AUXOUT PSRR vs Frequency AVDD = 5V, 0dB CPI (CPI inputs terminated) 20191769 www.national.com 20191770 64 LM49370 AUXOUT PSRR vs Frequency AVDD = 3.3V, 0dB DAC (DAC inputs selected) AUXOUT PSRR vs Frequency AVDD = 5V, 0dB DAC (DAC inputs selected) 20191771 20191772 CPOUT PSRR vs Frequency AVDD = 3.3V, 0dB AUX (AUX inputs terminated) CPOUT PSRR vs Frequency AVDD = 5V, 0dB AUX (AUX inputs terminated) 20191773 20191774 CPOUT PSRR vs Frequency AVDD = 3.3V, 0dB DAC (DAC inputs selected) CPOUT PSRR vs Frequency AVDD = 5V, 0dB DAC (DAC inputs selected) 20191775 20191776 65 www.national.com LM49370 Earpiece PSRR vs Frequency AVDD = 3.3V, 0dB AUX (AUX inputs terminated) Earpiece PSRR vs Frequency AVDD = 5V, 0dB AUX (AUX inputs terminated) 20191777 20191778 Earpiece PSRR vs Frequency AVDD = 3.3V, 0dB CPI (CPI input terminated) Earpiece PSRR vs Frequency AVDD = 5V, 0dB CPI (CPI input terminated) 20191779 20191780 Earpiece PSRR vs Frequency AVDD = 3.3V, 0dB DAC (DAC input selected) Earpiece PSRR vs Frequency AVDD = 5V, 0dB DAC (DAC input selected) 20191781 www.national.com 20191782 66 LM49370 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB AUX, OCL 1.2V (AUX inputs terminated) Headphone PSRR vs Frequency AVDD = 5V, 0dB AUX, OCL 1.2V (AUX inputs terminated) 20191783 20191784 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB CPI, OCL 1.2V (CPI input terminated) Headphone PSRR vs Frequency AVDD = 5V, 0dB CPI, OCL 1.2V (CPI input terminated) 20191785 20191786 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB ADC, OCL 1.2V (DAC input selected) Headphone PSRR vs Frequency AVDD = 5V, 0dB ADC, OCL 1.2V (DAC input selected) 20191787 20191788 67 www.national.com LM49370 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB AUX, OCL 1.5V (AUX inputs terminated) Headphone PSRR vs Frequency AVDD = 5V, 0dB AUX, OCL 1.5V (AUX inputs terminated) 20191789 20191790 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB CPI, OCL 1.5V (CPI input terminated) Headphone PSRR vs Frequency AVDD = 5V, 0dB CPI, OCL 1.5V (CPI input terminated) 20191791 20191792 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB DAC, OCL 1.5V (DAC input selected) Headphone PSRR vs Frequency AVDD = 5V, 0dB DAC, OCL 1.5V (DAC input selected) 20191793 www.national.com 20191794 68 LM49370 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB AUX, SE (AUX inputs terminated) Headphone PSRR vs Frequency AVDD = 5V, 0dB AUX, SE (AUX inputs terminated) 20191795 20191796 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB CPI, SE (CPI input terminated) Headphone PSRR vs Frequency AVDD = 5V, 0dB CPI, SE (CPI input terminated) 20191797 20191798 Headphone PSRR vs Frequency AVDD = 3.3V, 0dB DAC, SE (DAC input selected) Headphone PSRR vs Frequency AVDD = 5V, 0dB DAC, SE (DAC input selected) 20191799 201917a0 69 www.national.com LM49370 Loudspeaker PSRR vs Frequency AVDD = 3.3V, 0dB AUX (AUX inputs terminated) Loudspeaker PSRR vs Frequency AVDD = 5V, 0dB AUX (AUX inputs terminated) 20191730 20191731 Loudspeaker PSRR vs Frequency AVDD = 3.3V, 0dB CPI (CPI input terminated) Loudspeaker PSRR vs Frequency AVDD = 5V, 0dB CPI (CPI input terminated) 20191732 20191733 Loudspeaker PSRR vs Frequency AVDD = 3.3V, 0dB DAC (DAC input selected) Loudspeaker PSRR vs Frequency AVDD = 5V, 0dB DAC (DAC input selected) 20191734 www.national.com 20191735 70 INT/EXT MICBIAS PSRR vs Frequency AVDD = 5V, MICBIAS = 2.0V 201917a1 201917a2 INT/EXT MICBIAS PSRR vs Frequency AVDD = 3.3V, MICBIAS = 2.5V INT/EXT MICBIAS PSRR vs Frequency AVDD = 5V, MICBIAS = 2.5V 201917a3 201917a4 INT/EXT MICBIAS PSRR vs Frequency AVDD = 3.3V, MICBIAS = 2.8V INT/EXT MICBIAS PSRR vs Frequency AVDD = 5V, MICBIAS = 2.8V 201917a5 201917a6 71 www.national.com LM49370 INT/EXT MICBIAS PSRR vs Frequency AVDD = 3.3V, MICBIAS = 2.0V LM49370 INT/EXT MICBIAS PSRR vs Frequency AVDD = 5V, MICBIAS = 3.3V AUXOUT THD+N vs Frequency AVDD = 3.3V, 0dB, VOUT = 1VRMS, 5kΩ 201917a8 201917a7 AUXOUT THD+N vs Frequency AVDD = 5V, 0dB, VOUT = 1VRMS, 5kΩ CPOUT THD+N vs Frequency AVDD = 3.3V, 0dB, VOUT = 1VRMS, 5kΩ 201917a9 201917b0 CPOUT THD+N vs Frequency AVDD = 5V, 0dB, VOUT = 1VRMS, 5kΩ Earpiece THD+N vs Frequency AVDD = 3.3V, 0dB, POUT = 500mW, 32Ω 201917b1 www.national.com 201917b2 72 LM49370 Earpiece THD+N vs Frequency AVDD = 5V, 0dB, POUT = 50mW, 32Ω Headphone THD+N vs Frequency AVDD = 3.3V, OCL 1.5V, 0dB POUT = 7.5mW, 32Ω 201917b3 201917b4 Headphone THD+N vs Frequency AVDD = 5V, OCL 1.5V, 0dB POUT = 10mW, 32Ω Headphone THD+N vs Frequency AVDD = 3.3V, OCL 1.2V, 0dB POUT = 7.5mW, 32Ω 201917b5 201917b6 Headphone THD+N vs Frequency AVDD = 5V, OCL 1.2V, 0dB POUT = 10mW, 32Ω Headphone THD+N vs Frequency AVDD = 3.3V, SE, 0dB POUT = 7.5mW, 32Ω 201917b7 201917b8 73 www.national.com LM49370 Headphone THD+N vs Frequency AVDD = 5V, SE, 0dB POUT = 10mW, 32Ω Loudspeaker THD+N vs Frequency AVDD = 3.3V, POUT = 400mW 15μH+8Ω+15μH 20191736 201917b9 Loudspeaker THD+N vs Frequency AVDD = 5V, POUT = 400mW 15μH+8Ω+15μH Earpiece THD+N vs Output Power AVDD = 3.3V, 0dB AUX fOUT = 1kHz, 16Ω 20191737 201917c0 Earpiece THD+N vs Output Power AVDD = 5V, 0dB AUX fOUT = 1kHz, 16Ω Earpiece THD+N vs Output Power AVDD = 3.3V, 0dB AUX fOUT = 1kHz, 32Ω 201917c1 www.national.com 201917c2 74 LM49370 Earpiece THD+N vs Output Power AVDD = 5V, 0dB AUX fOUT = 1kHz, 32Ω Earpiece THD+N vs Output Power AVDD = 3.3V, 0dB CPI fOUT = 1kHz, 16Ω 201917c3 201917c4 Earpiece THD+N vs Output Power AVDD = 5V, 0dB CPI fOUT = 1kHz, 16Ω Earpiece THD+N vs Output Power AVDD = 3.3V, 0dB CPI fOUT = 1kHz, 32Ω 201917c5 201917c6 Earpiece THD+N vs Output Power AVDD = 5V, 0dB CPI fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 0dB DAC fOUT = 1kHz, 16Ω 201917c7 201917c8 75 www.national.com LM49370 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 0dB DAC fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 0dB DAC fOUT = 1kHz, 32Ω 201917c9 201917d0 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 0dB DAC fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 12dB DAC fOUT = 1kHz, 16Ω 201917d1 201917d2 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 12dB DAC fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 12dB DAC fOUT = 1kHz, 32Ω 201917d3 www.national.com 201917d4 76 LM49370 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 12dB DAC fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 0dB DAC fOUT = 1kHz, 16Ω 201917d5 201917d6 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 0dB DAC fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 0dB DAC fOUT = 1kHz, 32Ω 201917d7 201917d8 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 0dB DAC fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 12dB DAC fOUT = 1kHz, 16Ω 201917d9 201917e0 77 www.national.com LM49370 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 12dB DAC fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 12dB DAC fOUT = 1kHz, 32Ω 201917e1 201917e2 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 12dB DAC fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 0dB DAC fOUT = 1kHz, 16Ω 201917e3 201917e4 Headphone THD+N vs Output Power AVDD = 5V, SE, 0dB DAC fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 0dB DAC fOUT = 1kHz, 32Ω 201917e5 www.national.com 201917e6 78 LM49370 Headphone THD+N vs Output Power AVDD = 5V, SE, 0dB DAC fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 12dB DAC fOUT = 1kHz, 16Ω 201917e7 201917e8 Headphone THD+N vs Output Power AVDD = 5V, SE, 12dB DAC fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 12dB DAC fOUT = 1kHz, 32Ω 201917e9 201917f0 Headphone THD+N vs Output Power AVDD = 5V, SE, 12dB DAC fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 0dB AUX fOUT = 1kHz, 16Ω 201917f1 201917f2 79 www.national.com LM49370 Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 12dB AUX fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 0dB AUX fOUT = 1kHz, 16Ω 201917f3 201917f4 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 12dB AUX fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 0dB AUX fOUT = 1kHz, 32Ω 201917f5 201917f6 Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 12dB AUX fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 0dB AUX fOUT = 1kHz, 32Ω 201917f7 www.national.com 201917f8 80 LM49370 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 12dB AUX fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 0dB CPI fOUT = 1kHz, 16Ω 201917f9 201917g0 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 0dB CPI fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.2V, 0dB CPI fOUT = 1kHz, 32Ω 201917g1 201917g2 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.2V, 0dB CPI fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 0dB AUX fOUT = 1kHz, 16Ω 201917g3 201917g4 81 www.national.com LM49370 Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 12dB AUX fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 0dB AUX fOUT = 1kHz, 16Ω 201917g5 201917g6 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 12dB AUX fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 0dB AUX fOUT = 1kHz, 32Ω 201917g7 201917g8 Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 12dB AUX fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 0dB AUX fOUT = 1kHz, 32Ω 201917g9 www.national.com 201917h0 82 LM49370 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 12dB AUX fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 0dB CPI fOUT = 1kHz, 16Ω 201917h1 201917h2 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 0dB CPI fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, OCL 1.5V, 0dB CPI fOUT = 1kHz, 32Ω 201917h3 201917h4 Headphone THD+N vs Output Power AVDD = 5V, OCL 1.5V, 0dB CPI fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 0dB AUX fOUT = 1kHz, 16Ω 201917h5 201917h6 83 www.national.com LM49370 Headphone THD+N vs Output Power AVDD = 5V, SE, 0dB AUX fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 0dB AUX fOUT = 1kHz, 32Ω 201917h8 201917h7 Headphone THD+N vs Output Power AVDD = 5V, SE, 0dB AUX fOUT = 1kHz, 32Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 0dB CPI fOUT = 1kHz, 16Ω 201917h9 201917i0 Headphone THD+N vs Output Power AVDD = 5V, SE, 0dB CPI fOUT = 1kHz, 16Ω Headphone THD+N vs Output Power AVDD = 3.3V, SE, 0dB CPI fOUT = 1kHz, 32Ω 201917i1 www.national.com 201917i2 84 Loudspeaker THD+N vs Output Power AVDD = 3.3V, 0dB AUX fOUT = 1kHz, 15μH+8Ω+15μH 20191738 201917i3 Loudspeaker THD+N vs Output Power AVDD = 4.2V, 0dB AUX fOUT = 1kHz, 15μH+8Ω+15μH Loudspeaker THD+N vs Output Power AVDD = 5V, 0dB AUX fOUT = 1kHz, 15μH+8Ω+15μH 20191739 20191740 Loudspeaker THD+N vs Output Power AVDD = 3.3V, 0dB CPI fOUT = 1kHz, 15μH+8Ω+15μH Loudspeaker THD+N vs Output Power AVDD = 4.2V, 0dB CPI fOUT = 1kHz, 15μH+8Ω+15μH 20191741 20191742 85 www.national.com LM49370 Headphone THD+N vs Output Power AVDD = 5V, SE, 0dB CPI fOUT = 1kHz, 32Ω LM49370 Loudspeaker THD+N vs Output Power AVDD = 5V, 0dB CPI fOUT = 1kHz, 15μH+8Ω+15μH Loudspeaker THD+N vs Output Power AVDD = 3.3V, 0dB DAC fOUT = 1kHz, 15μH+8Ω+15μH 20191743 20191744 Loudspeaker THD+N vs Output Power AVDD = 4.2V, 0dB DAC fOUT = 1kHz, 15μH+8Ω+15μH Loudspeaker THD+N vs Output Power AVDD = 5V, 0dB DAC fOUT = 1kHz, 15μH+8Ω+15μH 20191745 20191746 AUXOUT THD+N vs Output Voltage AVDD = 3.3V, 0dB AUX fOUT = 1kHz, 5kΩ AUXOUT THD+N vs Output Voltage AVDD = 5V, 0dB AUX fOUT = 1kHz, 5kΩ 201917i4 www.national.com 201917i5 86 LM49370 AUXOUT THD+N vs Output Voltage AVDD = 3.3V, 0dB CPI fOUT = 1kHz, 5kΩ AUXOUT THD+N vs Output Voltage AVDD = 5V, 0dB CPI fOUT = 1kHz, 5kΩ 201917i6 201917i7 AUXOUT THD+N vs Output Voltage AVDD = 3.3V, 0dB DAC fOUT = 1kHz, 5kΩ AUXOUT THD+N vs Output Voltage AVDD = 5V, 0dB DAC fOUT = 1kHz, 5kΩ 201917i8 201917i9 AUXOUT THD+N vs Output Voltage AVDD = 3.3V, 12dB DAC fOUT = 1kHz, 5kΩ AUXOUT THD+N vs Output Voltage AVDD = 5V, 12dB DAC fOUT = 1kHz, 5kΩ 201917j0 201917j1 87 www.national.com LM49370 CPOUT THD+N vs Output Voltage AVDD = 3.3V, 0dB AUX fOUT = 1kHz, 5kΩ CPOUT THD+N vs Output Voltage AVDD = 5V, 0dB AUX fOUT = 1kHz, 5kΩ 201917j2 201917j3 CPOUT THD+N vs Output Voltage AVDD = 3.3V, 0dB DAC fOUT = 1kHz, 5kΩ CPOUT THD+N vs Output Voltage AVDD = 5V, 0dB DAC fOUT = 1kHz, 5kΩ 201917j5 201917j4 CPOUT THD+N vs Output Voltage AVDD = 3.3V, 6dB MIC fOUT = 1kHz, 5kΩ CPOUT THD+N vs Output Voltage AVDD = 5V, 6dB MIC fOUT = 1kHz, 5kΩ 201917j6 www.national.com 201917j7 88 LM49370 CPOUT THD+N vs Output Voltage AVDD = 3.3V, 12dB DAC fOUT = 1kHz, 5kΩ CPOUT THD+N vs Output Voltage AVDD = 5V, 12dB DAC fOUT = 1kHz, 5kΩ 201917j8 201917j9 CPOUT THD+N vs Output Voltage AVDD = 3.3V, 36dB MIC fOUT = 1kHz, 5kΩ CPOUT THD+N vs Output Voltage AVDD = 5V, 36dB MIC fOUT = 1kHz, 5kΩ 201917k0 201917k1 Headphone Crosstalk vs Frequency OCL 1.2V, 0dB AUX, 32Ω Headphone Crosstalk vs Frequency OCL 1.5V, 0dB AUX, 32Ω 201917k2 201917k3 89 www.national.com LM49370 Headphone Crosstalk vs Frequency SE, 0dB AUX, 32Ω 201917k4 www.national.com 90 LM49370 201917z3 14.0 LM49370 Demonstration Board Schematic Diagram 91 www.national.com LM49370 15.0 Demoboard PCB Layout 201917z9 Top Silkscreen www.national.com 92 LM49370 201917z8 Top Layer 93 www.national.com LM49370 201917z6 Mid Layer 1 www.national.com 94 LM49370 201917z7 Mid Layer 2 95 www.national.com LM49370 201917z4 Bottom Layer www.national.com 96 LM49370 201917z5 Bottom Silkscreen 97 www.national.com LM49370 16.0 Revision History www.national.com Rev Date Description 1.0 02/14/07 Initial released. 98 LM49370 17.0 Physical Dimensions inches (millimeters) unless otherwise noted 49 Bump micro SMDxt Package Order Number LM49370RL Dimensions: X1 = 3.924±0.03mm, X2 = 3.924±0.03mm, X3 = 0.650±0.75mm NS Package Number RLA49UUA 99 www.national.com LM49370 Audio Sub-System with an Ultra Low EMI, Spread Spectrum, Class D Loudspeaker Amplifier, a Dual-Mode Stereo Headphone Amplifier, and a Dedicated PCM Interface for Bluetooth Transceivers Notes THE CONTENTS OF THIS 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