wm8982gefl-v Wolfson Microelectronics plc, wm8982gefl-v Datasheet - Page 45

• Manufacturer Part Number: wm8982gefl-v
• Description: Mono Codec With Speaker Driver And Video Buffer
• Manufacturer: Wolfson Microelectronics plc

Pre-Production
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Figure 25 DAC Digital Limiter Operation
The limiter has a programmable upper threshold which is close to 0dB. Referring to Figure 25, in
normal operation (LIMBOOST=000 => limit only) signals below this threshold are unaffected by the
limiter.
LIMATK register bits) until the signal falls below the threshold. The limiter also has a lower threshold
1dB below the upper threshold.
amplified at a specific decay rate (controlled by LIMDCY register bits) until a gain of 0dB is reached.
Both threshold levels are controlled by the LIMLVL register bits. The upper threshold is 0.5dB above
the value programmed by LIMLVL and the lower threshold is 0.5dB below the LIMLVL value.
VOLUME BOOST
The limiter has programmable upper gain which boosts signals below the threshold to compress the
dynamic range of the signal and increase its perceived loudness. This operates as an ALC function
with limited boost capability. The volume boost is from 0dB to +12dB in 1dB steps, controlled by the
LIMBOOST register bits.
The output limiter volume boost can also be used as a stand alone digital gain boost when the limiter
is disabled.
Signals above the upper threshold are attenuated at a specific attack rate (set by the
When the signal falls below the lower threshold the signal is
PP, Rev 3.2, September 2008
WM8982
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