WM8731L WOLFSON [Wolfson Microelectronics plc], WM8731L Datasheet
WM8731L
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WM8731L Summary of contents
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... Portable Internet Audio CODEC with Headphone Driver and Programmable Sample Rates DESCRIPTION The WM8731 or WM8731L (WM8731/L) are low power stereo CODECs with an integrated headphone driver. The WM8731/L is designed specifically for portable MP3 audio and speech players and recorders. The WM8731 is also ideal for MD, CD-RW machines and DAT recorders ...
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... ORDERING INFORMATION ..................................................................................3 PIN CONFIGURATION – 28 PIN QFN ...................................................................4 ORDERING INFORMATION ..................................................................................4 PIN DESCRIPTION ................................................................................................5 ABSOLUTE MAXIMUM RATINGS.........................................................................6 RECOMMENDED OPERATING CONDITIONS – WM8731 ...................................6 RECOMMENDED OPERATING CONDITIONS – WM8731L.................................6 ELECTRICAL CHARACTERISTICS – WM8731 ....................................................7 TERMINOLOGY .....................................................................................................9 POWER CONSUMPTION – WM8731 ..................................................................10 ELECTRICAL CHARACTERISTICS – WM8731L................................................11 TERMINOLOGY ...................................................................................................13 POWER CONSUMPTION – WM8731L................................................................14 MASTER CLOCK TIMING....................................................................................15 DIGITAL AUDIO INTERFACE – ...
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... WM8731 / WM8731L PIN CONFIGURATION - 28 PIN SSOP 28 1 DBVDD 27 2 CLKOUT 26 3 BCLK 25 4 DACDAT 24 5 DACLRC 23 6 ADCDAT 22 7 ADCLRC 21 8 HPVDD 20 9 LHPOUT 19 10 RHPOUT 18 11 HPGND 17 12 LOUT 16 13 ROUT 14 15 AVDD ORDERING INFORMATION TEMPERATURE DEVICE RANGE o WM8731SEDS -25 to +85 ...
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... WM8731 / WM8731L PIN CONFIGURATION – 28 PIN QFN TOP VIEW ORDERING INFORMATION TEMPERATURE DEVICE RANGE o WM8731LSEFL - WM8731LSEFL/R - WM8731SEFL - WM8731SEFL/R -25 to +85 C Note: Reel quantity = 3,500 w AVDD PACKAGE RANGE 28-lead QFN 1.8 to 3.6V (Pb-free) 28-lead QFN 1.8 to 3.6V (Pb-free, tape and reel) 28-lead QFN 2 ...
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... WM8731 / WM8731L PIN DESCRIPTION 28 PIN 28 PIN NAME SSOP QFN 1 5 DBVDD 2 6 CLKOUT 3 7 BCLK 4 8 DACDAT 5 9 DACLRC 6 10 ADCDAT 7 11 ADCLRC 8 12 HPVDD 9 13 LHPOUT 10 14 RHPOUT 11 15 HPGND 12 16 LOUT 13 17 ROUT 14 18 AVDD 15 19 AGND 16 20 VMID ...
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... The digital supply core voltage (DCVDD) must always be less than or equal to the analogue supply voltage (AVDD) RECOMMENDED OPERATING CONDITIONS – WM8731 PARAMETER Digital supply range (Core) Digital supply range (Buffer) Analogue supply range Ground DGND,AGND,HPGND RECOMMENDED OPERATING CONDITIONS – WM8731L PARAMETER Digital supply range (Core) Digital supply range (Buffer) Analogue supply range Ground DGND,AGND,HPGND w ...
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... WM8731 / WM8731L ELECTRICAL CHARACTERISTICS – WM8731 Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. PARAMETER Digital Logic Levels (CMOS Levels) Input LOW level Input HIGH level Output LOW Output HIGH Power On Reset Threshold (DCVDD) DCVDD Threshold On -> Off Hysteresis DCVDD Threshold Off -> ...
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... WM8731 / WM8731L Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. Microphone Input to ADC @ 0dB Gain 48kHz (40kΩ Source Impedance. See Figure 12) Input Signal Level (0dB) Signal to Noise Ratio (Note 1,3) Dynamic Range (Note 3) Total Harmonic Distortion ...
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... WM8731 / WM8731L Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. Stereo Headphone Output 0dB Full scale output voltage Max Output Power Signal to Noise Ratio (Note 1, 3) Total Harmonic Distortion Power Supply Rejection Ratio Programmable Gain Programmable Gain Step Size ...
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... WM8731 / WM8731L POWER CONSUMPTION – WM8731 MODE DESCRIPTION Record and Playback Oscillator enabled 0 0 External MCLK 0 0 Oscillator and 0 1 CLKOUT disabled, No microphone Playback Only Oscillator enabled 0 0 External MCLK 0 1 Record Only Line Record oscillator enabled Line Record, using ...
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... WM8731 / WM8731L ELECTRICAL CHARACTERISTICS – WM8731L Test Conditions AVDD, HPVDD, DBVDD = 1.8V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. PARAMETER Digital Logic Levels (CMOS Levels) Input LOW level Input HIGH level Output LOW Output HIGH Power On Reset Threshold (DCVDD) DCVDD Threshold On -> Off Hysteresis DCVDD Threshold Off -> ...
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... WM8731 / WM8731L Test Conditions AVDD, HPVDD, DBVDD = 1.8V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. Microphone Input to ADC @ 0dB Gain 48kHz (40kΩ Source Impedance. See Figure 12) Input Signal Level (0dB) Signal to Noise Ratio (Note 1,3) Dynamic Range (Note 3) Total Harmonic Distortion ...
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... WM8731 / WM8731L Test Conditions AVDD, HPVDD, DBVDD = 1.8V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. Stereo Headphone Output 0dB Full scale output voltage Max Output Power Signal to Noise Ratio (Note 1,3) Total Harmonic Distortion Power Supply Rejection Ratio Programmable Gain Programmable Gain Step Size ...
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... WM8731 / WM8731L POWER CONSUMPTION – WM8731L MODE DESCRIPTION Record and Playback All active, oscillator 0 0 enabled Playback Only Oscillator enabled 0 0 Record Only Line Record oscillator enabled Mic Record oscillator enabled Side Tone (Microphone Input to Headphone Output) Clock stopped ...
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... WM8731 / WM8731L MASTER CLOCK TIMING XTI/MCLK Figure 1 System Clock Timing Requirements Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. PARAMETER SYMBOL System Clock Timing Information XTI/MCLK System clock pulse width high XTI/MCLK System clock pulse width ...
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... WM8731 / WM8731L DIGITAL AUDIO INTERFACE – MASTER MODE WM8731 CODEC Note: ADC and DAC can run at different rates Figure 3 Master Mode Connection BCLK (Output) ADCLRC DAC/LRC (Outputs) ADCDAT DACDAT Figure 4 Digital Audio Data Timing – Master Mode Test Conditions AVDD, HPVDD, DBDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated ...
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... WM8731 / WM8731L DIGITAL AUDIO INTERFACE – SLAVE MODE BCLK ADCLRC WM8731 DACLRC CODEC ADCDAT DACDAT Note: The ADC and DAC can run at different rates Figure 5 Slave Mode Connection t BCLK DACLRC/ ADCLRC DACDAT ADCDAT Figure 6 Digital Audio Data Timing – Slave Mode Test Conditions AVDD, HPVDD, DBVDD = 3 ...
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... WM8731 / WM8731L MPU INTERFACE TIMING CSB SCLK SDIN Figure 7 Program Register Input Timing - 3-Wire MPU Serial Control Mode Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. PARAMETER Program Register Input Information SCLK rising edge to CSB rising ...
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... WM8731 / WM8731L t 3 SDIN SCLK t 1 Figure 8 Program Register Input Timing – 2-Wire MPU Serial Control Mode Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T 256fs unless otherwise stated. PARAMETER Program Register Input Information SCLK Frequency SCLK Low Pulsewidth SCLK High Pulsewidth ...
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... WM8731 / WM8731L DEVICE DESCRIPTION INTRODUCTION The WM8731 low power audio CODEC designed specifically for portable audio products. It’s features, performance and low power consumption make it ideal for portable MP3 players and portable mini-disc players. The CODEC includes line and microphone inputs to the on-board ADC, line and headphone outputs from the on-board DAC, a crystal oscillator, configurable digital audio interface and a choice wire MPU control interface ...
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... WM8731 / WM8731L AVDD VMID AGND MICBIAS RLINEIN Mute Reg 02h RLINEIN VOL MUTE MUTE +12 to -34.5dB, 1.5dB Steps, Reg 02h 0dB/ MICIN 20dB MIC BOOST Reg 08h MUTE MUTE LLINEIN VOL LLINEIN Mute +12 to -34.5dB, 1.5dB Steps, Reg 00h Reg 00h ...
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... WM8731 / WM8731L The gain between the line inputs and the ADC is logarithmically adjustable from +12dB to –34.5dB in 1.5dB steps under software control. The ADC Full Scale input is 1.0V rms at AVDD = 3.3 volts. Any voltage greater than full scale will possibly overload the ADC and cause distortion. Note that the full scale input tracks directly with AVDD ...
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... WM8731 / WM8731L AGND Figure 11 Line Input Application Drawing For interfacing to a typical CD system recommended that the input is scaled to ensure that there is no clipping of the signal 5.6k 5.6k 220pF 1µF. R1 and R2 form a resistive divider to attenuate the 2 Vrms output from a CD player Vrms level, so avoiding overloading the inputs ...
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... WM8731 / WM8731L Or alternatively to calculate the value of Rmic to achieve a given gain, G1. The internal 50k and 10k resistors have a tolerance of 15%. For Rmicext = 90k G = 0.5 (-6dB) and for Rmicext = x10 (14dB). nd The 2 gain for low sensitivity microphones. The microphone input can therefore be configured with a variable gain of between -6dB and 14dB on ...
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... WM8731 / WM8731L R1 and R2 form part of the biasing network (refer to Microphone Bias section below). R1 connected to MICBIAS is necessary only for electret type microphones that require a voltage bias. R2 should always be present to prevent the microphone input from charging to a high voltage which may damage the microphone on connection. R1 and R2 should be large so as not to attenuate the signal from the microphone, which can have source impedance greater than 2k ...
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... WM8731 / WM8731L The use of multi-bit feedback and high oversampling rates reduces the effects of jitter and high frequency noise. The ADC Full Scale input is 1.0V rms at AVDD = 3.3 volts. Any voltage greater than full scale will possibly overload the ADC and cause distortion. Note that the full scale input tracks directly with AVDD ...
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... WM8731 / WM8731L There are several types of ADC filters, frequency and phase responses of these are shown in Digital Filter Characteristics. The filter types are automatically configured depending on the sample rate chosen. Refer to the sample rate section for more details. DAC FILTERS The DAC filters perform true 24 bit signal processing to convert the incoming digital audio data from the digital audio interface at the specified sample rate to multi-bit oversampled data for processing by the analogue DAC ...
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... WM8731 / WM8731L The DAC converts the multi-level digital audio data stream from the DAC digital filters into high quality analogue audio. LINE OUTPUTS The WM8731/L provides two low impedance line outputs LLINEOUT and RLINEOUT, suitable for driving typical line loads of impedance 10K and capacitance 50pF. The line output is used to selectively sum the outputs from the DAC or/and the Line inputs in bypass mode ...
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... WM8731 / WM8731L The recommended external components are shown in Figure 20. LINEOUT Figure 20 Line Outputs Application Drawing Recommended values are C1 = 10µ 47k 100 Ω. C1 forms a DC blocking capacitor to the line outputs. R1 prevents the output voltage from drifting so protecting equipment connected to the line output. R2 forms a de-coupling resistor preventing abnormal loads from disturbing the device ...
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... WM8731 / WM8731L A zero cross detect circuit is provided at the input to the headphones under the control of the LZCEN and RZCEN bits of the headphone output control register. Using these controls the volume control values are only updated when the input signal to the gain stage is close to the analogue ground level. ...
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... WM8731 / WM8731L The recommended external components required to complete the application are shown in Figure 22. HPOUT Figure 22 Headphone Output Application Drawing Recommended values are C1 = 220uF (10V electrolytic 47k C1 forms a DC blocking capacitor to isolate the dc of the HPOUT from the headphones. R1 form a pull down resistor to discharge C1 to prevent the voltage at the connection to the headphones from rising to a level that may damage the headphones ...
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... WM8731 / WM8731L The bypass mode is selected under software control using the BYPASS microphone bit as shown in Table 10. In true bypass mode, the output from the DAC (DACSEL) and (SIDETONE) should be de- selected from the line output block. However this can also be used to sum the DAC output, Line Inputs together and microphone inputs ...
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... WM8731 / WM8731L The side tone mode and attenuation is selected under software control using the SIDETONE bit as shown in Table 11. In true side tone the output from the DAC (DACSEL) and line inputs (BYPASS) should be deselected from the line output block. However, this can also be used to sum the DAC output, line inputs and microphone inputs together ...
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... WM8731 / WM8731L CRYSTAL OSCILLATOR The WM8731/L includes a crystal oscillator circuit that allows the audio system’s reference clock to be generated on the device. This is available to the rest of the audio system in buffered form on CLKOUT. The crystal oscillator is a low radiation type, designed for low EMI. A typical application circuit is shown in Figure 25 ...
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... WM8731 / WM8731L DIGITAL AUDIO INTERFACES WM8731/L may be operated in either one of the 4 offered audio interface modes. These are: • Right justified • Left justified 2 • • DSP mode All four of these modes are MSB first and operate with data bits. ...
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... WM8731 / WM8731L DACLRC/ ADCLRC BCLK 1 BCLK DACDAT ADCDAT MSB 2 Figure Mode Right Justified mode is where the LSB is available on the rising edge of BCLK preceding a DACLRC or ADCLRC transition, yet MSB is still transmitted first. DACLRC/ ADCLRC BCLK DACDAT/ 1 ADCDAT MSB Figure 28 Right Justified Mode In DSP/PCM mode, the left channel MSB is available on either the 1 edge of BCLK (selectable by LRP) following a rising edge of LRC ...
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... WM8731 / WM8731L Figure 30 DSP/PCM Mode Audio Interface (mode B, LRP=0) In all modes DACLRC and ADCLRC must always change on the falling edge of BCLK, refer to Figure 26, Figure 27, Figure 28, Figure 29 and Figure 30. Operating the digital audio interface in DSP mode allows ease of use for supporting the various sample rates and word lengths ...
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... WM8731 / WM8731L To accommodate system timing requirements the interpretation of BCLK maybe inverted, this is controlled vias the software shown in Table 15. This is especially appropriate for DSP mode. ADCDAT lines are always outputs. They power up and return from standby low. DACDAT is always an input expected to be set low by the audio interface controller when the WM8731/L is powered off or in standby ...
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... WM8731 / WM8731L MASTER AND SLAVE MODE OPERATION The WM8731/L can be configured as either a master or slave mode device master mode device the WM8731/L controls sequencing of the data and clocks on the digital audio interface slave device the WM8731/L responds with data to the clocks it receives over the digital audio interface ...
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... WM8731 / WM8731L AUDIO DATA SAMPLING RATES The WM8731/L provides for two modes of operation (normal and USB) to generate the required DAC and ADC sampling rates. Normal and USB modes are programmed under software control according to the table below. In Normal mode, the user controls the sample rate by using an appropriate MCLK or crystal frequency and the sample rate control register setting ...
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... WM8731 / WM8731L SAMPLING RATE ADC kHz 44.1 44.1 8 (Note 1) 8 (Note 1) 88.2 Table 18 Normal Mode Sample Rate Look-up Table Notes not exact, actual = 8.018kHz 2. All other combinations of BOSR and SR[3:0] that are not in the truth table are invalid The BOSR bit represents the base over-sampling rate. This is the rate that the WM8731/L digital signal processing is carried out at ...
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... WM8731 / WM8731L The exact sample rates achieved are defined by the relationships in Table 19 below. TARGET SAMPLING RATE kHz 8 32 44.1 48 88.2 96 Table 19 Normal Mode Actual Sample Rates 128/192fs NORMAL MODE The Normal Mode sample rates are designed for standard 256fs and 384fs MCLK rates. However the WM8731/L is also capable of being clocked from a 128 or 192fs MCLK for application over limited sampling rates as shown in the table below ...
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... WM8731 / WM8731L USB MODE SAMPLE RATES In USB mode the MCLK/crystal oscillator input is 12MHz only. SAMPLING RATE ADC kHz 48 44.1 (Note 2) 48 44.1 (Note ((Note (Note 88.2 (Note 3) Table 21 USB Mode Sample Rate Look-up Table Notes not exact, actual = 8.021kHz 2. 44.1k not exact, actual = 44.118kHz 3 ...
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... WM8731 / WM8731L the data across the digital interface is correctly synchronised at the 8.021kHz and 44.117kHz rates. The exact sample rates supported for all combinations are defined by the relationships in Table 22 below. TARGET SAMPLING RATE kHz 8 32 44.1 48 88.2 96 Table 22 USB Mode Actual Sample Rates ...
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... WM8731 / WM8731L 3-WIRE (SPI COMPATIBLE) SERIAL CONTROL MODE The WM8731/L can be controlled using a 3-wire serial interface. SDIN is used for the program data, SCLK is used to clock in the program data and CSB is use to latch in the program data. The 3-wire interface protocol is shown in Figure 33. ...
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... WM8731 / WM8731L Once the WM8731/L has acknowledged a correct address, the controller will send eight data bits (bits B15-B8). WM8731/L will then acknowledge the sent data by pulling SDIN low for one clock pulse. The controller will then send the remaining eight data bits (bits B7-B0) and the WM8731/L will then acknowledge again by pulling SDIN low ...
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... WM8731 / WM8731L MICPD: Simultaneously powers down both the Microphone Input and Microphone Bias. If this is done dynamically, audible pops through the ADC will result. This will only be audible if the Microphone Input is selected to the ADC at the time. If the state of MICPD is changed then the controlling DSP or microprocessor should switch to select the Line Inputs as input to the ADC (INSEL) before changing MICPD ...
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... WM8731 / WM8731L The device can be powered off by writing to the POWEROFF bit of the Power Down register. In POWEROFF mode the Control Interface and a small portion of the digital remain active. The analogue VMID reference is disabled STANDBY mode the crystal oscillator and/or CLKOUT pin can be independently controlled. Refer to Table 28. ...
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... WM8731 / WM8731L REGISTER ADDRESS 0000000 Left Line In 0000001 Right Line In 0000010 Left Headphone Out w BIT LABEL DEFAULT 4:0 LINVOL[4:0] 10111 ( 0dB ) 7 LINMUTE 1 8 LRINBOTH 0 4:0 RINVOL[4:0] 10111 ( 0dB ) 7 RINMUTE 1 8 RLINBOTH 0 6:0 LHPVOL 1111001 [6:0] ( 0dB ) 7 LZCEN 0 8 LRHPBOTH 0 Production Data DESCRIPTION Left Channel Line Input Volume Control 11111 = +12dB ...
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... WM8731 / WM8731L REGISTER ADDRESS 0000011 Right Headphone Out 0000100 Analogue Audio Path Control w BIT LABEL DEFAULT 6:0 RHPVOL 1111001 [6:0] ( 0dB ) 7 RZCEN 0 8 RLHPBOTH 0 0 MICBOOST 0 1 MUTEMIC 1 2 INSEL 0 3 BYPASS 1 4 DACSEL 0 5 SIDETONE 0 7:6 SIDEATT[1:0] 00 Production Data DESCRIPTION Right Channel Headphone Output ...
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... WM8731 / WM8731L REGISTER ADDRESS 0000101 Digital Audio Path Control 0000110 Power Down Control w BIT LABEL DEFAULT 0 ADCHPD 0 2:1 DEEMP[1: DACMU 1 4 HPOR 0 0 LINEINPD 1 1 MICPD 1 2 ADCPD 1 3 DACPD 1 4 OUTPD 1 5 OSCPD 0 6 CLKOUTPD 0 7 POWEROFF 1 Production Data DESCRIPTION ...
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... WM8731 / WM8731L REGISTER ADDRESS 0000111 Digital Audio Interface Format 0001000 Sampling Control w BIT LABEL DEFAULT 1:0 FORMAT[1:0] 10 3:2 IWL[1: LRP 0 5 LRSWAP BCLKINV 0 0 USB/ 0 NORMAL 1 BOSR 0 5:2 SR[3:0] 0000 6 CLKIDIV2 0 7 CLKODIV2 0 Production Data DESCRIPTION Audio Data Format Select 11 = DSP Mode, frame sync + 2 data ...
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... WM8731 / WM8731L REGISTER ADDRESS 0001001 Active Control 0001111 Reset Register Table 30 Register Map Description 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 responses of all filters is shown in the proceeding pages ...
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... WM8731 / WM8731L DAC FILTERS Mode Group Delay 0 11/FS 1 18/FS 2 5/FS 3 5/FS Table 32 ADC/DAC Digital Filters Group Delay TERMINOLOGY 1. Stop Band Attenuation (dB) - the degree to which the frequency spectrum is attenuated (outside audio band) 2. Pass-band Ripple – any variation of the frequency response in the pass-band region w ADC FILTERS ...
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... WM8731 / WM8731L DAC FILTER RESPONSES 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 35 DAC Digital Filter Frequency Response –Type 0 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 37 DAC Digital Filter Frequency Response –Type 1 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 39 DAC Digital Filter Frequency Response –Type ...
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... WM8731 / WM8731L 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 41 DAC Digital Filter Frequency Response –Type 3 ADC FILTER RESPONSES 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 43 ADC Digital Filter Frequency Response –Type 0 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 45 ADC Digital Filter Frequency Response –Type ...
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... WM8731 / WM8731L 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 47 ADC Digital Filter Frequency Response –Type 2 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 49 ADC Digital Filter Frequency Response –Type 3 ADC HIGH PASS FILTER The WM8731/L has a selectable digital high pass filter to remove DC offsets. The filter response is characterised by the following polynomial ...
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... WM8731 / WM8731L DIGITAL DE-EMPHASIS CHARACTERISTICS -10 0 2000 4000 6000 8000 Frequency (Fs) Figure 51 De-Emphasis Frequency Response (32kHz -10 0 5000 10000 Frequency (Fs) Figure 53 De-Emphasis Frequency Response (44.1kHz -10 0 5000 10000 Frequency (Fs) Figure 55 De-Emphasis Frequency Response (48kHz) w 0.4 0.3 0.2 0.1 0 -0.1 -0 ...
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... WM8731 / WM8731L APPLICATIONS INFORMATION RECOMMENDED EXTERNAL COMPONENTS Figure 57 External Components Diagram w Production Data PD Rev 4.3 August 2006 59 ...
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... WM8731 / WM8731L MINIMISING POP NOISE AT THE ANALOGUE OUTPUTS To minimise any pop or click noise when the system is powered up or down, the following procedures are recommended. POWER UP SEQUENCE • • • • • POWER DOWN SEQUENCE • • w Switch on power supplies. By default the WM8731 is in Standby Mode, the DAC is digitally muted and the Audio Interface and Outputs are all OFF. Set all required bits in the Power Down register (0Ch) to ‘ ...
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... WM8731 / WM8731L PACKAGE DIMENSIONS - SSOP DS: 28 PIN SSOP (10.2 x 5.3 x 1.75 mm Dimensions Symbols (mm) MIN NOM A ----- A 0. 1.65 1. 0.22 c 0.09 D 9.90 10.20 e 0.65 BSC E 7.40 7.80 E 5.00 5. 0.55 0.75 L 1.25 REF 1 θ JEDEC.95, MO-150 REF: NOTES: A. ALL LINEAR DIMENSIONS ARE IN MILLIMETERS. B. THIS DRAWING IS SUBJECT TO CHANGE WITHOUT NOTICE. ...
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... WM8731 / WM8731L PACKAGE DIMENSIONS - QFN FL: 28 PIN QFN PLASTIC PACKAGE 5 CORNER D2 TIE BAR B D2 EXPOSED 2 6 GROUND PADDLE ccc B e BOTTOM VIEW (A3 SEATING PLANE SIDE VIEW Dimensions (mm) Symbols MIN NOM A 0.85 0. 0.02 A3 0.2 REF b 0.18 0.23 D 5.00 BSC D2 3 ...
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... WM8731 / WM8731L IMPORTANT NOTICE Wolfson Microelectronics plc (“Wolfson”) products and services are sold subject to Wolfson’s terms and conditions of sale, delivery and payment supplied at the time of order acknowledgement. Wolfson warrants performance of its products to the specifications in effect at the date of shipment. Wolfson reserves the right to make changes to its products and specifications or to discontinue any product or service without notice ...