WM8973LGEFL WOLFSON Wolfson Microelectronics plc, WM8973LGEFL Datasheet
WM8973LGEFL
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WM8973LGEFL Summary of contents
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Stereo CODEC for Portable Audio Applications DESCRIPTION The WM8973L is a low power, high quality stereo CODEC designed for portable digital audio applications. The device integrates complete interfaces to stereo or mono microphones and a stereo headphone. External component ...
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WM8973L DESCRIPTION .......................................................................................................1 FEATURES.............................................................................................................1 APPLICATIONS .....................................................................................................1 BLOCK DIAGRAM .................................................................................................1 TABLE OF CONTENTS .........................................................................................2 PIN CONFIGURATION...........................................................................................4 ORDERING INFORMATION ..................................................................................4 PIN DESCRIPTION ................................................................................................5 ABSOLUTE MAXIMUM RATINGS.........................................................................6 RECOMMENDED OPERATION CONDITIONS .....................................................6 ELECTRICAL CHARACTERISTICS ......................................................................7 OUTPUT PGA’S LINEARITY ......................................................................................... 9 HEADPHONE OUTPUT THD VERSUS ...
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Advanced Information APPLICATIONS INFORMATION .........................................................................53 RECOMMENDED EXTERNAL COMPONENTS........................................................... 53 LINE INPUT CONFIGURATION................................................................................... 54 MICROPHONE INPUT CONFIGURATION .................................................................. 54 MINIMISING POP NOISE AT THE ANALOGUE OUTPUTS ........................................ 55 POWER MANAGEMENT EXAMPLES ......................................................................... 55 IMPORTANT NOTICE ..........................................................................................57 ADDRESS:................................................................................................................... 57 w WM8973L AI ...
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... RINPUT2 LINPUT2 26 27 RINPUT1 28 LINPUT1 MODE 29 CSB 30 31 SDIN SCLK ORDERING INFORMATION ORDER CODE TEMPERATURE RANGE WM8973LGEFL/V - +85 C WM8973LGEFL/RV - +85 C Note: Reel quantity = 3500 LOUT2 15 ROUT2 14 HPGND LOUT1 13 ROUT1 12 11 OUT3 MONOOUT 10 9 ADCLRC 6 ...
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Advanced Information PIN DESCRIPTION PIN NO NAME Digital Input 1 MCLK Supply 2 DCVDD Supply 3 DBVDD 4 DGND Supply 5 BCLK Digital Input / Output 6 DACDAT Digital Input 7 DACLRC Digital Input / Output 8 ADCDAT Digital Output ...
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WM8973L ABSOLUTE MAXIMUM RATINGS Absolute Maximum Ratings are stress ratings only. Permanent damage to the device may be caused by continuously operating at or beyond these limits. Device functional operating limits and guaranteed performance specifications are given under Electrical Characteristics ...
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Advanced Information ELECTRICAL CHARACTERISTICS Test Conditions DCVDD = 1.5V, DBVDD = 3.3V, AVDD = HPVDD = 3.3V, T data unless otherwise stated. PARAMETER Analogue Inputs (LINPUT1, RINPUT1, LINPUT2, RINPUT2, LINPUT3, RINPUT3) to ADC out Full Scale Input Signal Level (for ...
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WM8973L Test Conditions DCVDD = 1.5V, DBVDD = 3.3V, AVDD = HPVDD = 3.3V, T data unless otherwise stated. PARAMETER Speaker Output (LOUT2/ROUT2 with 8 Output Power at 1% THD Abs. Max Power Ouptut Total Harmonic Distortion Signal to Noise ...
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Advanced Information OUTPUT PGA’S LINEARITY 10.000 0.000 Output PGA Gains -10.000 -20.000 -30.000 -40.000 -50.000 -60.000 -70.000 40 50 2.000 1.750 Output PGA Gain Step Size 1.500 1.250 1.000 0.750 0.500 0.250 0.000 ...
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WM8973L HEADPHONE OUTPUT THD VERSUS POWER 0 Headphone Pow er vs THD+N (32Ohm load) -20 -40 -60 -80 -100 Headphone Pow er vs THD+N (16Ohm load) -20 -40 -60 -80 -100 ...
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Advanced Information POWER CONSUMPTION The power consumption of the WM8973L depends on the following factors. Supply voltages: Reducing the supply voltages also reduces supply currents, and therefore results in significant power savings, especially in the digital sections of the WM8973L. ...
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WM8973L SIGNAL TIMING REQUIREMENTS SYSTEM CLOCK TIMING MCLK Figure 1 System Clock Timing Requirements Test Conditions CLKDIV2=0, DCVDD = 1.42V, DBVDD = 3.3V, DGND = 0V, T unless otherwise stated. PARAMETER System Clock Timing Information MCLK System clock pulse width ...
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Advanced Information Test Conditions DCVDD = 1.42V, DBVDD = 3.3V, DGND = 0V, T otherwise stated. PARAMETER Bit Clock Timing Information BCLK rise time (10pF load) BCLK fall time (10pF load) BCLK duty cycle (normal mode, BCLK = MCLK/n) BCLK ...
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WM8973L CONTROL INTERFACE TIMING – 3-WIRE MODE CSB SCLK SDIN Figure 4 Control Interface Timing – 3-Wire Serial Control Mode Test Conditions DCVDD = 1.42V, DBVDD = 3.3V, DGND = 0V, T otherwise stated. PARAMETER Program Register Input Information SCLK ...
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Advanced Information CONTROL INTERFACE TIMING – 2-WIRE MODE SDIN SCLK Figure 5 Control Interface Timing – 2-Wire Serial Control Mode Test Conditions DCVDD = 1.42V, DBVDD = 3.3V, DGND = 0V, T otherwise stated. PARAMETER Program Register Input Information SCLK ...
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WM8973L DEVICE DESCRIPTION INTRODUCTION The WM8973L is a low power audio CODEC offering a combination of high quality audio, advanced features, low power and small size. These characteristics make it ideal for portable digital audio applications such as MP3 and ...
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Advanced Information DC MEASUREMENT For DC measurements (for example, battery voltage monitoring), the input signal at the LINPUT1 and/or RINPUT1 pins can be taken directly into the respective ADC, bypassing both PGA and microphone boost. The ADC output then becomes ...
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WM8973L MONO MIXING The stereo ADC can operate as a stereo or mono device, or the two channels can be mixed to mono, either in the analogue domain (i.e. before the ADC the digital domain (after the ADC). ...
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Advanced Information PGA CONTROL The PGA matches the input signal level to the ADC input range. The PGA gain is logarithmically adjustable from +30dB to –17.25dB in 0.75dB steps. Each PGA can be controlled either by the user or by ...
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WM8973L ANALOGUE TO DIGITAL CONVERTER (ADC) The WM8973L uses a multi-bit, oversampled sigma-delta ADC for each channel. The use of multi-bit feedback and high oversampling rates reduces the effects of jitter and high frequency noise. The ADC Full Scale input ...
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Advanced Information REGISTER R5 (05h) ADC and DAC Control R27 (1Bh) Table 9 ADC Signal Path Control HPFLREN Table 10 ADC Highpass Filter Enable Modes DIGITAL ADC VOLUME CONTROL The output of the ADCs can be ...
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WM8973L REGISTER ADDRESS R21 (15h) Left ADC Digital Volume R22 (16h) Right ADC Digital Volume Table 11 ADC Digital Volume Control w BIT LABEL DEFAULT 7:0 LADCVOL 11000011 [7:0] ( 0dB ) 8 LAVU 0 7:0 RADCVOL 11000011 [7:0] ( ...
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Advanced Information AUTOMATIC LEVEL CONTROL (ALC) The WM8973L has an automatic level control that aims to keep a constant recording volume irrespective of the input signal level. This is achieved by continuously adjusting the PGA gain so that the signal ...
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WM8973L REGISTER ADDRESS R17 (11h) ALC Control 1 R18 (12h) ALC Control 2 R19 (13h) ALC Control 3 Table 12 ALC Control PEAK LIMITER To prevent clipping when a large signal occurs just after a period of quiet, the ALC ...
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Advanced Information NOISE GATE When the signal is very quiet and consists mainly of noise, the ALC function may cause “noise pumping”, i.e. loud hissing noise during silence periods. The WM8973L has a noise gate function that prevents noise pumping ...
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WM8973L 3D STEREO ENHANCEMENT The WM8973L has a digital 3D enhancement option to artificially increase the separation between the left and right channels. This effect can be used for recording or playback, but not for both simultaneously. Selection of 3D ...
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Advanced Information OUTPUT SIGNAL PATH The WM8973L output signal paths consist of digital filters, DACs, analogue mixers and output drivers. The digital filters and DACs are enabled when the WM8973L is in ‘playback only’ or ‘record and playback’ mode. The ...
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WM8973L GRAPHIC EQUALISER The WM8973L has a digital graphic equaliser and adaptive bass boost function. This function operates on digital audio data before it is passed to the audio DACs. Bass enhancement can take two different forms: Linear bass control: ...
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Advanced Information DIGITAL TO ANALOGUE CONVERTER (DAC) After passing through the graphic equaliser filters, digital ‘de-emphasis’ can be applied to the audio data if necessary (e.g. when the data comes from a CD with pre-emphasis used in the recording). De-emphasis ...
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WM8973L OUTPUT MIXERS The WM8973L provides the option to mix the DAC output signal with analogue line-in signals from the LINPUT1/2/3, RINPUT1/2/3 pins or a mono differential input (LINPUT1 – RINPUT1) or (LINPUT2 – RINPUT2), selected by DS (see Table ...
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Advanced Information REGISTER ADDRESS R36 (24h) Right Mixer Control (1) R37 (25h) Right Mixer Control (2) Table 22 Right Output Mixer Control REGISTER ADDRESS R38 (26h) Mono Mixer Control (1) R39 (27h) Mono Mixer Control (2) Table 23 Mono Output ...
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WM8973L ANALOGUE OUTPUTS LOUT1/ROUT1 OUTPUTS The LOUT1 and ROUT1 pins can drive a 16 Output and Line Output sections, respectively). The signal volume on LOUT1 and ROUT1 can be independently adjusted under software control by writing to LOUT1VOL and ROUT1VOL, ...
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Advanced Information LOUT2/ROUT2 OUTPUTS The LOUT2 and ROUT2 output pins are essentially similar to LOUT1 and ROUT1, but they are independently controlled and can also drive an 8 speaker drive, the ROUT2 signal must be inverted (ROUT2INV = 1), so ...
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WM8973L ENABLING THE OUTPUTS Each analogue output of the WM8973L can be separately enabled or disabled. The analogue mixer associated with each output is powered on or off along with the output pin. All outputs are disabled by default. To ...
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Advanced Information REGISTER ADDRESS R24 (18h) Additional Control (2) Table 31 Headphone Switch Figure 9 Example Headset Detection Circuit Using Normally-Open Switch Figure 10 Example Headset Detection Circuit Using Normally-Closed Switch w BIT LABEL DEFAULT 6 HPSWEN 0 5 HPSWPOL ...
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WM8973L THERMAL SHUTDOWN The speaker and headphone outputs can drive very large currents. To protect the WM8973L from overheating a thermal shutdown circuit is included. If the device temperature reaches approximately 0 150 C and the thermal shutdown circuit is ...
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Advanced Information LINE OUTPUT The analogue outputs, LOUT1/ROUT1 and LOUT2/ROUT2, can be used as line outputs. Additionally, OUT3 and MONOOUT can be used as a stereo line-out by setting OUT3SW=11 (reg. 24) and ensuring the contents of registers 38 and ...
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WM8973L AUDIO DATA FORMATS In Left Justified mode, the MSB is available on the first rising edge of BCLK following an LRCLK transition. The other bits up to the LSB are then transmitted in order. Depending on word length, BCLK ...
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Advanced Information follows left channel data. Depending on word length, BCLK frequency and sample rate, there may be unused BCLK cycles between the LSB of the right channel data and the next sample. DACLRC/ ADCLRC BCLK DACDAT/ ADCDAT Figure 19 ...
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WM8973L AUDIO INTERFACE CONTROL The register bits controlling audio format, word length and master / slave mode are summarised in Table 33. MS selects audio interface operation in master or slave mode. In Master mode BCLK, ADCLRC and DACLRC are ...
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Advanced Information MASTER MODE ADCLRC AND DACLRC ENABLE In Master mode, by default ADCLRC is disabled when the ADC is disabled and DACLRC is disabled when the DAC is disabled. Register bit LRCM, register 24(18h) bit[2] changes the control so ...
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WM8973L accuracy depends on the accuracy of MCLK. If MCLK changes, the sample rates change proportionately. Note that some sample rates (e.g. 44.1kHz in USB mode) are approximated, i.e. they differ from their target value by a very small amount. ...
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Advanced Information CONTROL INTERFACE SELECTION OF CONTROL MODE The WM8973L is controlled by writing to registers through a serial control interface. A control word consists of 16 bits. The first 7 bits (B15 to B9) are address bits that select ...
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WM8973L The WM8973L has two possible device addresses, which can be selected using the CSB pin. CSB STATE Table 40 2-Wire MPU Interface Address Selection POWER SUPPLIES The WM8973L can use up to four separate power supplies: AVDD / AGND: ...
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Advanced Information POWER MANAGEMENT The WM8973L has two control registers that allow users to select which functions are active. For minimum power consumption, unused functions should be disabled. To avoid any pop or click noise important to enable ...
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WM8973L SAVING POWER BY REDUCING OVERSAMPLING RATE The default mode of operation of the ADC and DAC digital filters is in 128x oversampling mode. Under the control of ADCOSR and DACOSR the oversampling rate may be halved. This will result ...
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Advanced Information REGISTER MAP ADDRESS REGISTER remarks (Bit 15 – (00h) 0000000 Left Input volume R1 (01h) 0000001 Right Input volume R2 (02h) 0000010 LOUT1 volume R3 (03h) 0000011 ROUT1 volume R4 (04h) 0000100 Reserved R5 (05h) 0000101 ...
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WM8973L DIGITAL FILTER CHARACTERISTICS The ADC and DAC employ different digital filters. There are 4 types of digital filter, called Type and 3. The performance of Types 0 and 1 is listed in the table below, the ...
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Advanced Information DAC FILTER RESPONSES 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 23 DAC Digital Filter Frequency Response – Type 0 Figure 24 DAC Digital Filter Ripple – Type 0 0 -20 -40 -60 ...
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WM8973L 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 29 DAC Digital Filter Frequency Response – Type 3 Figure 30 DAC Digital Filter Ripple – Type 3 ADC FILTER RESPONSES 0 -20 -40 -60 -80 ...
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Advanced Information 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 35 ADC Digital Filter Frequency Response – Type 2 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 37 ADC Digital ...
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WM8973L -10 0 5000 10000 Frequency (Fs) Figure 41 De-emphasis Frequency Response (44.1kHz -10 0 5000 10000 Frequency (Fs) Figure 43 De-emphasis Frequency Response (48kHz) HIGHPASS FILTER The WM8973L has ...
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Advanced Information APPLICATIONS INFORMATION RECOMMENDED EXTERNAL COMPONENTS Figure 46 Recommended External Components Diagram w WM8973L AI Rev 3.2 July 2004 53 ...
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WM8973L COMPONENT SUGGESTED REFERENCE VALUE C1 – C4 100nF C5 – C6 10uF C7 – C12 1uF C13 2.2uF C14 & C15 220uF C16 100nF C17 10uF C18 100nF C19 10uF C20 100nF C21 10uF Table 45 External Components Descriptions ...
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Advanced Information The recommended application circuit is shown above. R1 and R2 form part of the biasing network (refer to Microphone Bias section). R1 connected to MICBIAS is necessary only for electret type microphones that require a voltage bias. R2 ...
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WM8973L PACKAGE DIMENSIONS FL: 32 PIN QFN PLASTIC PACKAGE SEATING PLANE Exposed lead Half etch tie bar DETAIL 2 Dimensions (mm) Symbols ...
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Advanced Information IMPORTANT NOTICE Wolfson Microelectronics plc (WM) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before ...