WM8986_07 WOLFSON [Wolfson Microelectronics plc], WM8986_07 Datasheet - Page 22

• Manufacturer Part Number: WM8986_07
• Description: Multimedia DAC With Class D Headphone and Line Out
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

WM8986
DEVICE DESCRIPTION
INTRODUCTION
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The WM8986 is a low power audio IC combining a high quality stereo audio DAC with flexible line
and microphone input and output processing.
FEATURES
The chip offers great flexibility in use, and so can support many different modes of operation as
follows:
HI-FI DAC
The hi-fi DAC provides high quality audio playback suitable for all portable audio hi-fi type
applications, including MP3 players and portable disc players of all types.
OUTPUT MIXERS
Flexible mixing is provided on the outputs of the device. A stereo mixer is provided for the stereo
headphone or line outputs, LOUT1/ROUT1, and additional summers on the OUT3/OUT4 outputs
allow for an optional differential or stereo line output on these pins. Gain adjustment PGAs are
provided for the LOUT1/ROUT1 and LOUT2/ROUT2 outputs, and signal switching is provided to
allow for all possible signal combinations.
OUT3 and OUT4 can be configured to provide an additional stereo or mono differential lineout from
the output of the DACs, the mixers or the input microphone boost stages. They can also provide a
midrail reference for pseudo differential inputs to external amplifiers.
LINE INPUTS (AUXL, AUXR)
The inputs, AUXL and AUXR, can be used as a stereo line input (e.g. melody chip or FM radio) or as
an input for warning tones (or ‘beeps’) etc. These inputs can be summed into the output paths, along
with the microphone preamp outputs.
MICROPHONE INPUTS
Two pairs of stereo microphone inputs are provided, allowing a pair of stereo microphones to be
pseudo-differentially connected, with user defined gain. The provision of the common mode input pin
for each stereo input allows for rejection of common mode noise on the microphone inputs (level
depends on gain setting chosen).
Total gain through the microphone paths of up to +55.25dB can be selected.
AUDIO INTERFACES
The WM8986 has a standard audio interface, to support the transmission of stereo data to and from
the chip. This interface is a 3 wire standard audio interface which supports a number of audio data
formats including:
The interface can operate in master or slave modes.
CONTROL INTERFACES
To allow full software control over all features, the WM8986 offers a choice of 2 or 3 wire control
interface. It is fully compatible and an ideal partner for a wide range of industry standard
microprocessors, controllers and DSPs.
Selection of the mode is via the MODE pin. In 2 wire mode, the address of the device is fixed as
0011010.
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DSP/PCM Mode (a burst mode in which LRC sync plus 2 data packed words are transmitted)
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PP, Rev 3.1, February 2007
Pre-Production
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