WM8974GEFL/V Wolfson Microelectronics, WM8974GEFL/V Datasheet - Page 43

• Manufacturer Part Number: WM8974GEFL/V
• Description: Audio CODECs Mono Codec with Spkr
• Manufacturer: Wolfson Microelectronics

Specifications of WM8974GEFL/V

• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-24
• Minimum Operating Temperature: - 25 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Production Data
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Table 36 Output Boost Control
Table 37 Output Boost Stage Details
SPKOUTP/SPKOUTN OUTPUTS
Table 38 Speaker Mixer Control
The SPKOUT pins can drive a single bridge tied 8 Ω speaker or two headphone loads of 16Ω or 32Ω
or a line output (see Headphone Output and Line Output sections, respectively). The signal to be
output on SKPKOUT comes from the Speaker Mixer circuit and can be any combination of the DAC
output, the Bypass path (output of the boost stage) and the AUX input. The SPKOUTP/N volume is
controlled by the SPKVOL register bits. Note that gains over 0dB may cause clipping if the signal is
large. The SPKMUTE register bit causes the speaker outputs to be muted (the output DC level is
driven out). The output pins remains at the same DC level (VMIDOP), so that no click noise is
produced when muting or un-muting.
The SPKOUTN pin always drives out an inverted version of the SPKOUTP signal.
R49
Output control
R1
Power
management 1
0
1
R50
Speaker mixer
control
R40
Bypass path
attenuation control
MONOBOOST
SPKBOOST/
REGISTER
REGISTER
ADDRESS
ADDRESS
1x
1.5x
STAGE GAIN
2
3
8
0
1
5
1
BIT
BIT
OUTPUT
SPKBOOST
MONOBOOST
BUFDCOPEN
DAC2SPK
BYP2SPK
AUX2SPK
SPKATTN
LABEL
LABEL
AVDD/2
1.5xAVDD/2
OUTPUT DC
LEVEL
DEFAULT
0
0
0
DEFAULT
1
0
0
0
Inverting
Non-inverting
CONFIGURATION
OUTPUT STAGE
37 for details)
0=No boost (outputs are inverting buffers)
1 = 1.5x gain boost
for details)
0=No boost (output is inverting buffer)
1=1.5x gain boost
Dedicated buffer for DC level shifting output
stages when in 1.5x gain boost configuration.
0=Buffer disabled
1=Buffer enabled (required for 1.5x gain boost)
Speaker output boost stage control (see Table
Mono output boost stage control (see Table 37
Output of DAC to speaker mixer input
0 = not selected
1 = selected
Bypass path (output of input boost stage) to
speaker mixer input
0 = not selected
1 = selected
Output of auxiliary amplifier to speaker mixer
input
0 = not selected
1 = selected
Attenuation control for bypass path (output
of input boost stage) to speaker mixer input
0 = 0dB
1 = -10dB
PD, Rev 4.5, September 2008
DESCRIPTION
DESCRIPTION
WM8974
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