WM8945
Production Data
ANALOGUE OUTPUTS
The speaker outputs are highly configurable and may be used in many different ways. The output
mixers can be configured to generate mono or stereo, single-ended or differential outputs. The Class
AB Speaker output driver can deliver up to 400mW into an 8 speaker in BTL mode. Alternatively,
the Speaker outputs can deliver 40mW to a stereo 16 headphone load.
LINE OUTPUT
The line output LINEOUTL is the external connection to the MIXOUTL mixer. This is a single-ended
output driver.
Note that single-ended line output can also be provided on SPKOUTL and SPKOUTR.
SPEAKER OUTPUTS
The speaker outputs SPKOUTL and SPKOUTR are the external connections to the Speaker Output
mixers. These outputs are intended for a mono speaker or headphone in BTL configuration or for a
twin mono line load.
In a typical application, a BTL output from the DAC may be generated at the speaker outputs by
routing the inverted DAC signal to one output and the non-inverted DAC signal to the other.
The auxiliary inputs AUX1 or AUX2 may be routed to the mono speaker by enabling the respective
signal path in either the Left or Right speaker output mixer. (Note that these signals should not be
enabled in both mixers at once; this will lead to cancellation at the BTL output.)
EXTERNAL COMPONENTS FOR LINE OUTPUT
In single-ended output configurations, DC blocking capacitors are required at the output pins
(LINEOUTL, SPKOUTL and SPKOUTR). See “Applications Information” for details of these
components.
Note that these components are not required for differential (BTL) output modes.
PD, May 2011, Rev 4.1
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
