WM8985GEFL Wolfson Microelectronics, WM8985GEFL Datasheet - Page 34

• Manufacturer Part Number: WM8985GEFL
• Description: Audio CODECs Multimedia CODEC with Class D HP
• Manufacturer: Wolfson Microelectronics

Specifications of WM8985GEFL

• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-32
• Minimum Operating Temperature: - 25 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8985
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AUXILLIARY INPUTS
INPUT BOOST
Figure 17 Input Boost Stage
There are two auxiliary inputs, AUXL and AUXR which can be used for a variety of purposes such as
stereo line inputs or as a ‘beep’ input signal to be mixed with the outputs.
The AUXL/R inputs can be used as a line input to the input BOOST stage which has adjustable gain
of -12dB to +6dB in 3dB steps, with an additional "off" state (i.e. not connected to ADC input). See
the INPUT BOOST section for further details.
The AUXL/R inputs can also be mixed into the output channel mixers, with a gain of -15dB to +6dB
plus off.
Each of the stereo input PGA stages is followed by an input BOOST circuit. The input BOOST
circuit has 3 selectable inputs: the input microphone PGA output, the AUX amplifier output and the
L2/R2 input pin (can be used as a line input, bypassing the input PGA). These three inputs can be
mixed together and have individual gain boost/adjust as shown in Figure 17.
PD, Rev 4.6, July 2009
Production Data
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