NCS8353 ONSEMI [ON Semiconductor], NCS8353 Datasheet - Page 13

• Manufacturer Part Number: NCS8353
• Description: Stereo 20W/Ch Class D Audio Power Amplifier with Programmable Power Limit and Selectable Gain
• Manufacturer: ONSEMI [ON Semiconductor]

cases these pop and click phenomena occur during the
following power sequences:
•
•
•
momentary current will flow through the loudspeaker.
When current flows through the voice coil of a loudspeaker
it causes the diaphragm to move thus causing a popping and
clicking sound.
circuitry that creates a slow ramp to bias the amplifier during
Due to the voltage changes in the audio signal chain a
The NCS8353 includes pop and click suppression
Power supply power-up or power down (codec or amp).
Entering or releasing from shutdown/mute (codec or
amp).
State changes in the audio codec; e.g., switching
between audio sources.
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the previously mentioned power sequences. In order to
eliminate “pop and click” noises during transition, the
output power in the load must not be established or cutoff
suddenly. When logic high is applied to the shutdown pin,
the internal biasing voltage rises quickly and once the output
DC level is around the common mode voltage, the gain is
established slowly. This method to turn on the device is
optimized in terms of rejection of “pop and click” noises.
The device has the same behavior when it is turned-off by a
logic low on the shutdown pin. No power is delivered to the
load 150 ms after a falling edge on the shutdown pin. Due to
the fast turn on and off times, the shutdown signal can be
used as a mute signal as well.