WM8740EDS WOLFSON [Wolfson Microelectronics plc], WM8740EDS Datasheet
WM8740EDS
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WM8740EDS Summary of contents
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High Performance 192kHz Stereo DAC DESCRIPTION The WM8740 is a very high performance stereo DAC designed for audio applications such as CD, DVD, home theatre systems, set top boxes and digital TV. The WM8740 supports data input word ...
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WM8740 DESCRIPTION .......................................................................................................1 FEATURES.............................................................................................................1 APPLICATIONS .....................................................................................................1 BLOCK DIAGRAM .................................................................................................1 PIN CONFIGURATION...........................................................................................3 ORDERING INFORMATION ..................................................................................3 PIN DESCRIPTION ................................................................................................4 ABSOLUTE MAXIMUM RATINGS.........................................................................5 RECOMMENDED OPERATING CONDITIONS .....................................................6 ELECTRICAL CHARACTERISTICS ......................................................................6 DEVICE DESCRIPTION.........................................................................................9 SYSTEM CLOCK .......................................................................................................... 9 AUDIO DATA INTERFACE ....................................................................................9 NORMAL SAMPLE RATE ...
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... DIN 2 BCKIN 3 MODE8X 4 SCLK 5 DIFFHW 6 DGND 7 DVDD 8 AVDDR 9 AGNDR 10 VMIDR 11 12 VOUTRP VOUTRN 13 AGND 14 ORDERING INFORMATION TEMPERATURE DEVICE RANGE WM8740EDS -25 to +85 C WM8740SEDS -25 to +85 C Reel Quantity: 2,000 w ML/I2S 28 MC/DM1 27 MD/DM0 26 MUTEB 25 MODE 24 CSBIWO 23 RSTB 22 ZERO 21 AVDDL 20 AGNDL 19 VMIDL 18 VOUTLP 17 VOUTLN ...
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WM8740 PIN DESCRIPTION PIN NAME TYPE 1 LRCIN Digital input 2 DIN Digital input 3 BCKIN Digital input 4 MODE8X Digital input 5 SCLK Digital input 6 DIFFHW Digital input 7 DGND Supply 8 DVDD Supply 9 AVDDR Supply 10 ...
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WM8740 PIN NAME TYPE 23 CSBIWO Digital input Internal pull-down 24 MODE Digital input Internal pull-up 25 MUTEB Digital input Internal pull-up 26 MD/DM0 Digital input Internal pull-up 27 MC/DM1 Digital input Internal pull-up 28 ML/I2S Digital input Internal pull-up ...
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WM8740 RECOMMENDED OPERATING CONDITIONS PARAMETER Digital supply range Analogue supply range Ground AGND, DGND Difference DGND to AGND Analogue supply current Digital supply current Analogue supply current Digital supply current Note: DVDD must be equal to, or less than the ...
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WM8740 Test Conditions AVDD, DVDD = 5V, AGND, DGND = 0V, T PARAMETER SYMBOL Analogue Output Levels Output level differential Minimum resistance load Maximum capacitance load Output DC level Reference Levels Potential divider resistance Voltage at VMIDL/VMIDR POR (Power-On Reset) ...
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WM8740 SCKI Figure 2 System Clock Timing Requirements Test Conditions AVDD, DVDD = 5V, AGND, DGND = 0V, T PARAMETER System Clock Timing Information System clock pulse width high System clock pulse width low System clock cycle time ML/I2S MC/DM1 ...
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WM8740 DEVICE DESCRIPTION The WM8740 is a high performance 128fs oversampling rate stereo DAC employing a novel 64 level sigma delta DAC design which provides optimised signal-to-noise performance and clock jitter tolerance ideally suited to high quality audio ...
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WM8740 NORMAL SAMPLE RATE In normal mode, the data is input serially on one pin for both left and right channels. Data can be “right justified” meaning that the last 16 bits (depending on chosen PCM word ...
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WM8740 INPUT SAMPLE RATE Due to the higher speed of the interface mode, audio data is input on two pins. The MODE pin (pin 24) is used as the second input for the ...
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WM8740 DE-EMPHASIS CONTROL MDDM1 PIN Table 2 De-Emphasis Control AUDIO INPUT FORMAT ML/I2S PIN Table 3 Audio Input Format SOFT MUTE MUTEB PIN 25 H Table 4 Soft Mute A logic low on the ...
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WM8740 REGISTER MAP WM8740 controls the special functions using 4 program registers, which are 16-bits long. These registers are all loaded through input pin MD/DM0. After the 16 data bits are clocked in, ML/I2S is used to latch in the ...
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WM8740 Table 7 Attenuation Control Level Bit 2 in Reg3 is used to control the attenuator (ATC). When ATC is “high”, the attenuation data loaded in program register 0 is used for both the left and the right channels. When ...
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WM8740 POLARITY OF LR INPUT CLOCK The left channel data for a particular sample instant is always input first, then the right channel data. LRP (REG3, B1) Table 12 Polarity of LR Input Clock INDIVIDUAL OR COMMON ATTENUTATION CONTROL ATC ...
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WM8740 SOFTWARE DIFFERENTIAL MONO MODE To control the WM8740 in software differential mode register M4 must be written to. A ‘key’ register write must be made to register M2 to allow access to register M4 which is ‘locked’ as default. ...
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WM8740 MUTE MODES The device has various mute modes. Reg bit OPE = ‘1’ MUTEB pin AUTOMUTE (detect 1024 zero input samples) Reg bit MUT Gain = 00 (left and right) RAM initialise Loss of system clock No LRCLK or ...
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WM8740 FILTER RESPONSES Figure 8 Digital Filter Response (Sharp Roll-off Mode) Figure 10 Digital Filter Response (Slow Roll-off Mode) 0 -20 -40 -60 -80 -100 -120 0 0.2 0.4 0.6 0.8 1 Frequency (Fs) Figure 12 Digital Filter Response 128fs ...
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WM8740 1 0.8 0.6 0.4 0.2 0 -0.2 -0 Time (input samples) Figure 13 Impulse Response (Normal Roll-off, no De-emphasis) 0.0 -1.0 -2.0 -3.0 -4.0 -5.0 -6.0 -7.0 -8.0 -9.0 -10.0 0 2000 4000 6000 8000 ...
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WM8740 0.4 0.3 0.2 0.1 0.0 -0.1 -0.2 -0.3 -0.4 0 2000 4000 6000 8000 10000 Frequency (Fs) Figure 19 De-emphasis frequency response error (fs=44.1kHz) w 0.4 0.3 0.2 0.1 0.0 -0.1 -0.2 -0.3 -0.4 0 12000 14000 16000 18000 ...
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WM8740 RECOMMENDED EXTERNAL COMPONENTS DVDD + DGND Software I/F or Hardware Control Audio Serial Data I/F System Clock Input Notes: 1. AGND and DGND should be connected as close to the WM8740 as possible ...
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WM8740 SUGGESTED DIFFERENTIAL OUTPUT FILTER CIRCUIT Figure 22 Suggested Differential Output Filter Circuit RECOMMENDED DUAL DIFFERENTIAL HARDWARE SETUP Figure 23 Recommended Dual Differential Hardware Setup w Production Data PD Rev 4.0 April 2004 22 ...
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WM8740 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 10.20 ...
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