WM8725 Wolfson Microelectronics plc, WM8725 Datasheet
WM8725
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WM8725 Summary of contents
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... DESCRIPTION WM8725 is a high-performance stereo DAC designed for use in portable audio equipment, video CD players and similar applications. It comprises selectable normal or I compatible serial data interfaces for 16 to 24-bit digital inputs, high performance digital filters, and sigma-delta output DACs, achieving an excellent 99dB signal-to-noise performance ...
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... WM8725 DESCRIPTION ................................................................................................................1 FEATURES......................................................................................................................1 APPLICATIONS ..............................................................................................................1 BLOCK DIAGRAM ..........................................................................................................1 TABLE OF CONTENTS ..................................................................................................2 PIN CONFIGURATION....................................................................................................3 ORDERING INFORMATION ...........................................................................................3 ABSOLUTE MAXIMUM RATINGS..................................................................................4 RECOMMENDED OPERATING CONDITIONS ..............................................................4 ELECTRICAL CHARACTERISTICS ...............................................................................5 PIN DESCRIPTION .........................................................................................................6 INTERNAL POWER ON RESET .............................................................................................6 DEVICE DESCRIPTION..................................................................................................8 INTRODUCTION .....................................................................................................................8 DAC CIRCUITS .......................................................................................................................8 SERIAL DATA INTERFACE ....................................................................................................9 SYSTEM CLOCK ..................................................................................................................10 RECOMMENDED EXTERNAL COMPONENTS ...........................................................11 DETAIL OF RECOMMENDED EXTERNAL COMPONENTS SHOWING THE EXTERNAL LOW PASS FILTER ...
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... CAP 5 10 VOUTR 6 GND 7 ORDERING INFORMATION DEVICE TEMPERATURE RANGE +85 WM8725GED - +85 WM8725GED/RV Note: Reel quantity: 3,000 w SCKI FORMAT DEEMPH NC MUTE 9 VOUTL 8 VDD PACKAGE MOISTURE SENSITIVITY C 14-lead SOIC (lead free) C 14-lead SOIC (Pb-free, tape and reel) Production Data ...
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... WM8725 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 at the test conditions specified. ESD Sensitive Device. This device is manufactured on a CMOS process therefore generically susceptible to damage from excessive static voltages ...
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... WM8725 ELECTRICAL CHARACTERISTICS Test Conditions 5V, GND = 0V + 48kHz, SCKI = 256fs unless otherwise stated PARAMETER Digital Logic Levels Input LOW level Input HIGH level Analogue Output Levels Load Resistance Maximum capacitance load Output DC level Reference Levels Potential divider resistance ...
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... SCKI Digital input INTERNAL POWER ON RESET The WM8725 includes a n internal power-on reset circuit. This is shown in Figure 1.This reset circuit is used to reset the digital logic into a default state after power up. Figure 1 Internal Power on Reset Circuit The timing of the power on reset is shown in Figure 2 The circuit monitors VDD and VMID (CAP pin) and asserts PORB low when VMID is below the minimum threshold Vpor ...
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... Vpor_off Table 1 Power On/Off Reset Timing At power on, when VDD and VMID have been established, PORB is released and the WM8725 has been reset. At power down, PORB is asserted low whenever VMID drops below the minimum threshold of Vpor_off. If VDD is removed at any time, the internal power-on reset circuit is powered down and PORB will follow VDD ...
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... WM8725 attractive for many consumer type applications. DAC CIRCUITS The WM8725 DACs are designed to allow playback of 16-bit PCM audio or similar data with high resolution and low noise and distortion. Sample rates up to 96ks/s may be used, with much lower sample rates acceptable provided that the ratio of sample rate (LRCIN) to system clock is maintained at the required 256fs or 384fs times ...
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... SERIAL DATA INTERFACE WM8725 has serial interface formats that are fully compatible with both normal (MSB first, 16 bit right-justified) and I FORMAT is LOW, normal data format is selected. When the format is HIGH, I selected. It must be noted that in “ ...
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... SYSTEM CLOCK The system clock is used to operate the digital filters and the noise shaping circuits. The system clock input is at pin 14 (SCKI). The frequency of WM8725’s system clock should be set to 256fs or 384fs, (where fs is the audio sampling frequency). The sample rate is typically: 32 kHz, 44 ...
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... Analogue output signal tracks should be kept as short as possible and over the analogue ground plane reducing the possibility of losing signal quality LRCIN SCKI DIN 2 FORMAT BCKIN 3 DEEMPH WM8725 CAP 5 MUTE 6 VOUTR VOUTL GND 7 VDD - ...
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... WM8725 PACKAGE DIMENSIONS D: 14 PIN SOIC 3.9mm Wide Body 0.10 (0.004) Dimensions Symbols (MM) MIN A 1.35 A1 0.10 B 0.33 C 0.19 D 8.55 E 3.80 e 1.27 BSC H 5.80 h 0. REF: JEDEC.95, MS-012 NOTES: A. ALL LINEAR DIMENSIONS ARE IN MILLIMETERS (INCHES). B. THIS DRAWING IS SUBJECT TO CHANGE WITHOUT NOTICE. C. BODY DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSION, NOT TO EXCEED 0.25MM (0.010IN). ...
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... WM8725 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 ...