WM8766_05 WOLFSON [Wolfson Microelectronics plc], WM8766_05 Datasheet
WM8766_05
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WM8766_05 Summary of contents
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DAC DESCRIPTION The WM8766 is a multi-channel audio DAC ideal for DVD and surround sound processing applications for home hi-fi, automotive and other audio visual equipment. Three stereo 24-bit multi-bit sigma delta DACs are used with ...
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WM8766 DESCRIPTION .......................................................................................................1 FEATURES.............................................................................................................1 APPLICATIONS .....................................................................................................1 BLOCK DIAGRAM .................................................................................................1 TABLE OF CONTENTS .........................................................................................2 PIN CONFIGURATION 28 LEAD SSOP ...............................................................3 ORDERING INFORMATION ..................................................................................3 PIN DESCRIPTION – 28 LEAD SSOP...................................................................4 ABSOLUTE MAXIMUM RATINGS.........................................................................5 RECOMMENDED OPERATING CONDITIONS .....................................................6 ELECTRICAL CHARACTERISTICS ......................................................................6 TERMINOLOGY ............................................................................................................ ...
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Production Data PIN CONFIGURATION 28 LEAD SSOP ORDERING INFORMATION TEMPERATURE DEVICE RANGE o WM8766GEDS/V - WM8766GEDS/RV -25 to +85 C Note: Reel quantity = 2,000 w MOISTURE PACKAGE SENSITIVITY LEVEL 28-lead SSOP MSL3 (Pb-free) 28-lead SSOP ...
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WM8766 PIN DESCRIPTION – 28 LEAD SSOP PIN NAME 1 MODE Digital input 2 MCLK Digital input 3 BCLK Digital input/output 4 LRCLK Digital input/output 5 DVDD 6 DGND 7 DIN1 Digital input 8 DIN2 Digital input 9 DIN3 Digital ...
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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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WM8766 RECOMMENDED OPERATING CONDITIONS PARAMETER Digital supply range Analogue supply range AVDD, VREFP Ground AGND, VREFN, DGND Difference DGND to AGND Note: Digital supply DVDD must never be more than 0.3V greater than AVDD for normal operation of the device ...
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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. 2. All performance measurements done with 20kHz low pass filter, and where noted ...
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WM8766 DIGITAL AUDIO INTERFACE – MASTER MODE BCLK WM8766 LRCLK DAC DIN1/2/3 3 Figure 2 Audio Interface - Master Mode BCLK (Output) LRCLK (Output) DIN1/2/3 Figure 3 Digital Audio Data Timing – Master Mode Test Conditions AVDD, VREFP = 5V, ...
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Production Data DIGITAL AUDIO INTERFACE – SLAVE MODE BCLK WM8766 LRCLK DAC DIN1/2/3 3 Figure 4 Audio Interface – Slave Mode BCLK LRCLK DIN1/2/3 Figure 5 Digital Audio Data Timing – Slave Mode Test Conditions AVDD = 5V, DVDD = ...
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WM8766 MPU INTERFACE TIMING ML/I2S MC/IWL MD/DM Figure 6 SPI Compatible Control Interface Input Timing Test Conditions AVDD = 5V, DVDD = 3.3V, AGND, DGND = 0V, T PARAMETER MC/IWL rising edge to ML/I2S rising edge MC/IWL pulse cycle time ...
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Production Data INTERNAL POWER ON RESET CIRCUIT Figure 7 Internal Power on Reset Circuit Schematic The WM8768 includes an internal Power-On-Reset Circuit, as shown in Figure 7, which is used reset the digital logic into a default state after power ...
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WM8766 DEVICE DESCRIPTION INTRODUCTION WM8766 is a complete 6-channel DAC including digital interpolation and decimation filters and switched capacitor multi-bit sigma delta DACs with digital volume controls on each channel and output smoothing filters. The device is implemented as 3 ...
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Production Data SAMPLING RATE (LRCLK) 32kHz 44.1kHz 48kHz 96kHz 192kHz Table 6 System Clock Frequencies Versus Sampling Rate HARDWARE CONTROL MODES When the MODE pin is held high, the following hardware modes of operation are available. MUTE AND AUTOMUTE OPERATION ...
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WM8766 In hardware mode (MODE pin set high) the MUTE pin becomes a bi-directional pin. Therefore driven low the device will never softmute driven high then all channels will softmute immediately. However if the ...
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Production Data DIGITAL AUDIO INTERFACE MASTER AND SLAVE MODES The audio interface operates in either Slave or Master mode, selectable using the MS control bit. In both Master and Slave modes DIN1/2/3 are always inputs to the WM8766 and DOUT ...
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WM8766 AUDIO INTERFACE FORMATS Audio data is applied to the internal DAC filters via the Digital Audio Interface. 5 popular interface formats are supported: Left Justified mode Right Justified mode I2S mode DSP mode A DSP mode B All 5 ...
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Production Data RIGHT JUSTIFIED MODE In right justified mode, the LSB of DIN1/2/3 is sampled by the WM8766 on the rising edge of BCLK preceding a LRCLK transition. LRCLK are high during the left samples and low during the right ...
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WM8766 DSP MODE A In DSP mode A, the MSB of DAC channel 1 left data is sampled by the WM8766 on the second rising edge on BCLK following a LRCLK rising edge. DAC channel 1 right and DAC channels ...
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Production Data SOFTWARE CONTROL INTERFACE OPERATION The WM8766 is controlled using a 3-wire serial interface in software mode or pin programmable in hardware mode. The control mode is selected by the state of the MODE pin. 3-WIRE (SPI COMPATIBLE) SERIAL ...
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WM8766 DAC OUTPUT CONTROL The DAC output control word determines how the left and right inputs to the audio Interface are applied to the left and right DACs: REGISTER ADDRESS DAC Control DAC DIGITAL AUDIO INTERFACE CONTROL REGISTER Interface format ...
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Production Data be supported by setting the BCP register bit. Setting BCP to 1 inverts the polarity of BCLK to the inverse of that shown in Figure 13, Figure 14, Figure 15, Figure 16, and Figure 17. REGISTER ADDRESS Interface ...
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WM8766 DAC OUTPUT PHASE The DAC phase control word determines whether the output of each DAC is non-inverted or inverted REGISTER ADDRESS DAC Phase DIGITAL ZERO CROSS-DETECT The digital volume control also incorporates a zero cross detect circuit which detects ...
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Production Data SOFTWARE MODE The WM8766 can be muted in a number of different ways when in software mode (MODE pin pulled low). Refer to Figure 20 which shows a representation of the interaction between functions described below. Figure 20 ...
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WM8766 DMUTE AND MUTEALL Most simply, the WM8766 can be directly muted using the DMUTE register bit to control which channels are muted. The mute happens as soon as the serial write is performed. REGISTER ADDRESS DMUTE [2:0] Table 10 ...
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Production Data AUTOMUTE The WM8766 can automute by counting zero samples on the DIN1/2/3 inputs. When 1024 zero samples are counted on one channel, one of three internal zero flags (zflag1/2/3 shown in figure 2) is raised. Depending on the ...
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WM8766 DE-EMPHASIS MODE Each stereo DAC channel has an individual de-emphasis control bit: REGISTER ADDRESS DAC De-Emphahsis Table 14 De-emphasis Control Refer to Figure 30 for details of the De-Emphasis performance at different sample rates. REGISTER ADDRESS DAC DEEMPH POWERDOWN ...
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Production Data DACPD [2:0] Table 15 DAC Disable Control MASTER POWERDOWN This control bit powers down the references for the whole chip. Therefore for complete powerdown, all DACs should be powered down first before setting this bit. REGISTER ADDRESS Interface ...
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WM8766 MUTE PIN DECODE The MUTE pin can either be used as an output or an input. When used as an input the MUTE pins action can be controlled by setting the DZFM bit to select the corresponding DAC for ...
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Production Data DAC DIGITAL VOLUME CONTROL The DAC volume may also be adjusted in the digital domain using independent digital attenuation control registers REGISTER BIT LABEL ADDRESS 7:0 0000000 LDA1[7:0] Digital Attenuation 8 UPDATE DACL1 0000001 7:0 RDA1[6:0] Digital Attenuation ...
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WM8766 SOFTWARE REGISTER RESET Writing to register 11111 will cause a register reset, resetting all register bits to their default values. The device will be held in this reset state until a subsequent register write to any address is completed. ...
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Production Data DIGITAL FILTER CHARACTERISTICS PARAMETER Passband Passband ripple Stopband Stopband Attenuation Group Delay Table 17 Digital Filter Characteristics DAC FILTER RESPONSES 0 -20 -40 -60 -80 -100 -120 0 0.5 1 1.5 Frequency (Fs) Figure 21 DAC Digital Filter ...
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WM8766 DIGITAL DE-EMPHASIS CHARACTERISTICS - Frequency (kHz) Figure 25 De-Emphasis Frequency Response (32kHz - Frequency (kHz) Figure 27 De-Emphasis Frequency Response (44.1KHz) ...
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Production Data APPLICATIONS INFORMATION RECOMMENDED EXTERNAL COMPONENTS RECOMMENDED EXTERNAL COMPONENTS VALUES COMPONENT SUGGESTED REFERENCE VALUE C1 and 100 Table ...
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WM8766 SUGGESTED ANALOGUE LOW PASS POST DAC FILTERS It is recommended that a lowpass filter be applied to the output from each DAC channel for Hi Fi applications. Typically a second order filter is suitable and provides sufficient attenuation of ...
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Production Data PACKAGE DIMENSIONS 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 ...
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