WM8721_04 WOLFSON [Wolfson Microelectronics plc], WM8721_04 Datasheet
WM8721_04
Related parts for WM8721_04
WM8721_04 Summary of contents
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Internet Audio DAC with Integrated Headphone Driver DESCRIPTION The WM8721 is a low power stereo DAC with an integrated headphone driver. The WM8721 is designed specifically for portable MP3 audio and speech players. The WM8721 is also ideal for ...
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WM8721 / WM8721L DESCRIPTION ................................................................................................................1 FEATURES......................................................................................................................1 APPLICATIONS ..............................................................................................................1 BLOCK DIAGRAM ..........................................................................................................1 TABLE OF CONTENTS ..................................................................................................2 PIN CONFIGURATION....................................................................................................3 ORDERING INFORMATION ...........................................................................................3 PIN DESCRIPTION .........................................................................................................4 ABSOLUTE MAXIMUM RATINGS..................................................................................5 RECOMMENDED OPERATING CONDITIONS ..............................................................5 ELECTRICAL CHARACTERISTICS ...............................................................................6 TERMINOLOGY ..............................................................................................................7 POWER CONSUMPTION ...............................................................................................7 MASTER CLOCK ...
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Producion Data PIN CONFIGURATION DBVDD 1 BCLK 2 DACDAT 3 DACLRC 4 HPVDD 5 LHPOUT 6 7 RHPOUT HPGND 8 LOUT 9 ROUT 10 ORDERING INFORMATION TEMPERATURE DEVICE RANGE o XWM8721EDS - XWM8721EDS/R -25 to +85 ...
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WM8721 / WM8721L PIN DESCRIPTION 20 PIN NAME SSOP 1 DBVDD 2 BCLK 3 DACDAT 4 DACLRC 5 HPVDD 6 LHPOUT 7 RHPOUT 8 HPGND 9 LOUT 10 ROUT 11 AVDD 12 AGND 13 VMID 14 MODE 15 CSB 16 ...
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Production Data 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 ...
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WM8721 / WM8721L ELECTRICAL CHARACTERISTICS 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 ...
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Production Data Notes: 1. Ratio of output level with 1kHz full scale input, to the output level with all zeros into the digital input, measured ‘A’ weighted over a 20Hz to 20kHz bandwidth. 2. All performance measurements done with 20kHz ...
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WM8721 / WM8721L MASTER CLOCK TIMING MCLK Figure 1 System Clock Timing Requirements Test Conditions AVDD, HPVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T unless otherwise stated. PARAMETER System Clock Timing Information MCLK System ...
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Production Data DIGITAL AUDIO INTERFACE – SLAVE MODE BCLK DACLRC DACDAT Figure 3 Digital Audio Data Timing – Slave Mode Test Conditions AVDD, HPVDD, DVDD = 3.3V, AGND = 0V, DCVDD = 1.5V, DGND = 0V, T unless otherwise stated. ...
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WM8721 / WM8721L 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 edge SCLK pulse cycle time ...
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Production Data DEVICE DESCRIPTION INTRODUCTION The WM8721 is a low power audio DAC designed specifically for portable audio products. It’s features, performance and low power consumption make it ideal for portable MP3, CD and mini-disc players. The WM8721 includes line ...
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WM8721 / WM8721L The DAC digital filter can apply digital de-emphasis under software control, as shown in Table 2. The DAC can also perform a soft mute where the audio data is digitally brought to a mute level. This removes ...
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Production Data FROM DAC Figure 8 Line Output Schematic The line output is muted by either programming the DACMU (digital) bit as per table writing to the DACSEL (analogue) bit as per table 3. Whenever the DAC ...
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WM8721 / WM8721L HEADPHONE AMPLIFIER The WM8721 has a stereo headphone output available on LHPOUT and RHPOUT. The output is designed specifically for driving consumption. The headphone output includes a high quality volume level adjustment and mute ...
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Production Data The software control is given in Table 4. REGISTER ADDRESS 0000010 Left Headphone Out 0000011 Right Headphone Out Table 4 Headphone Output Software Control The recommended external components required to complete the application are shown in Figure 11. ...
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WM8721 / WM8721L 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 ...
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Production Data All four of these modes are MSB first and operate with data bits, except in right justified mode where 32 bit data is not supported. The digital audio interface receives the digital audio data for ...
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WM8721 / WM8721L Right Justified mode is where the LSB is available on the rising edge of BCLK preceding a DACLRC transition, yet MSB is still transmitted first. DACLRC BCLK DACDAT 1 MSB Figure 14 Right Justified Mode DSP mode ...
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Production Data In Master mode, DACLRC will be output with a 50:50 mark-space ratio with BCLK output at 64fs x base frequency (ie 48kHz). The exception again is in USB mode where BCLK is always 12MHz. So for example in ...
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WM8721 / WM8721L REGISTER ADDRESS 0000111 Digital Audio Interface Format Table 7 Digital Audio Interface Control Note: If right justified 32 bit mode is selected then the WM8721 defaults to 24 bits. MASTER AND SLAVE MODE OPERATION The WM8721 can ...
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Production Data As a master mode device the WM8721 controls the sequencing of data transfer (DACDAT) and output of clocks (BCLK, DACLRC) over the digital audio interface. It uses the timing generated from the MCLK input as the reference for ...
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WM8721 / WM8721L REGISTER ADDRESS 0001000 Sampling Control Table 9 Sample Rate Control NORMAL MODE SAMPLE RATES In normal mode MCLK is set up according to the desired sample rates of the DAC. For DAC sampling rates of 8, 32, ...
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Production Data The exact sample rates achieved are defined by the relationships in Table 11 below. TARGET SAMPLING RATE kHz 8 32 44.1 48 88.2 96 Table 11 Normal Mode Actual Sample Rates 128/192FS NORMAL MODE The Normal Mode sample ...
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WM8721 / WM8721L USB MODE SAMPLE RATES In USB mode the MCLK input is 12MHz only. SAMPLING RATE DAC kHz 44.1 (Note 2) 8 (Note 1) 88.2 (Note 3) Table 13 USB Mode Sample Rate Look-up Table Notes ...
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Production Data ACTIVATING DSP AND DIGITAL AUDIO INTERFACE To prevent any communication problems from arising across the Digital Audio Interface it is disabled (tristate) at power on. Once the Audio Interface and the Sampling Control has been programmed it is ...
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WM8721 / WM8721L 2-WIRE SERIAL CONTROL MODE The WM8721 supports a 2-wire MPU serial interface. The device operates as a slave device only. The WM8721 has one of two slave addresses that are selected by setting the state of pin ...
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Production Data POWER DOWN MODES The WM8721 contains power conservation modes in which various circuit blocks may be safely powered down in order to conserve power. This is software programmable as shown in Table 18. REGISTER ADDRESS 0000110 Power Down ...
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WM8721 / WM8721L REGISTER MAP The complete register map is shown in Table 21. The detailed description can be found in the relevant text of the device description. There are 9 registers with 9 bits per register. These can be ...
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Production Data REGISTER ADDRESS 0000011 Right Headphone Out 0000100 Audio Path Control 0000101 Digital Audio Path Control 0000110 Power Down Control w BIT LABEL DEFAULT 6:0 RHPVOL 1111001 [6:0] ( 0dB ) 7 RZCEN 0 8 RLHPBOTH 0 4 DACSEL ...
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WM8721 / WM8721L REGISTER ADDRESS 0000111 Digital Audio Interface Format 0001000 Sampling Control 0001001 Active Control 0001111 Reset Register Table 20 Register Map Description w BIT LABEL DEFAULT 1:0 FORMAT[1:0] 10 3:2 IWL[1: LRP 0 5 LRSWAP 0 ...
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Production Data Note: All other bits not explicitly defined in the register table should be set to zero unless specified otherwise (see Powerdown section). DIGITAL FILTER CHARACTERISTICS The DAC employs different digital filters. There are 4 types of digital filter, ...
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WM8721 DAC FILTER RESPONSES 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 20 DAC Digital Filter Frequency Response –Type 0 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 22 DAC ...
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Production Data 0 -20 -40 -60 -80 -100 0 0.5 1 1.5 Frequency (Fs) Figure 26 DAC Digital Filter Frequency Response –Type 3 DIGITAL DE-EMPHASIS CHARACTERISTICS -10 0 2000 4000 6000 8000 Frequency (Fs) Figure ...
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WM8721 -10 0 5000 10000 Frequency (Fs) Figure 32 De-Emphasis Frequency Response (48kHz) w 0.4 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 -0.4 15000 20000 0 Figure 33 De-Emphasis Error (48kHz) Production Data 5000 10000 ...
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Production Data RECOMMENDED EXTERNAL COMPONENTS 3. 0 0.1 F 1. Audio Serial Data I/F 2 3.3V 3-wire Interface 10k 14 2-wire Interface 15 3-wire or 2-wire 16 ...
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WM8721 PACKAGE DIMENSIONS DS: 20 PIN SSOP (7.2 x 5.3 x 1.75 mm Dimensions Symbols (mm) MIN NOM A ----- A 0. 1.65 1. 0.22 c 0.09 D 6.90 ...
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