WM8903 Datasheet, PDF (1/178 Pages) Wolfson Microelectronics plc – Ultra Low Power CODEC for Portable Audio Applications

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WM8903
Ultra Low Power CODEC for Portable Audio Applications
DESCRIPTION
The WM8903 is a high performance ultra-low power stereo
CODEC optimised for portable audio applications.
The device features stereo ground-referenced headphone
amplifiers using the Wolfson ‘Class W’ amplifier techniques -
incorporating an innovative dual-mode charge pump
architecture - to optimise efficiency and power consumption
during playback. The ground-referenced outputs eliminate
headphone coupling capacitors. Both headphone and line
outputs include common mode feedback paths to reject
ground noise.
Control sequences for audio path setup can be pre-loaded
and executed by an integrated sequencer to reduce
software driver development and eliminate pops and clicks
via Wolfson’s SilentSwitch™ technology.
The analogue input stage can be configured for single
ended or differential inputs. Up to 3 stereo microphone or
line inputs may be connected. The input impedance is
constant with PGA gain setting.
A stereo digital microphone interface is provided, which can
also be mixed with the mic/line signals at the output mixers.
A dynamic range controller provides compression and level
control to support a wide range of portable recording
applications. Anti-clip and quick release features offer good
performance in the presence of loud impulsive noises.
Common audio sampling frequencies are supported from a
range of external clocks, either directly or generated via the
Frequency Locked Loop (FLL).
The WM8903 can operate directly from a single 1.8V
switched supply. For optimal power consumption, the digital
core can be operated from a 1.0V supply.
FEATURES
 4.5mW power consumption for DAC to headphone
playback
 DAC SNR 96dB typical, THD -86dB typical
 ADC SNR 92dB typical, THD -80dB typical
 Control sequencer for pop minimised start-up and shut-
down
 Single register write for default start-up sequence
 Integrated FLL provides all necessary clocks
- Self-clocking modes allow processor to sleep
- All standard sample rates from 8kHz to 96kHz
 Stereo digital microphone input
 3 single ended inputs per stereo channel
 1 fully differential mic / line input per stereo channel
 Digital Dynamic Range Controller (compressor / limiter)
 Digital sidetone mixing
 Ground-referenced headphone driver
 Ground-referenced line outputs
 Stereo differential line driver for direct interface to WM9001
speaker driver
 40-pin QFN package (5x5mm)
APPLICATIONS
 Portable multimedia players
 Multimedia handsets
 Handheld gaming
WOLFSON MICROELECTRONICS plc
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Production Data, June 2012, Rev 4.5
Copyright 2012 Wolfson Microelectronics plc