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TDA7419

5.2

AutoZero

The AutoZero allows a reduction of the number of pins as well as external components by canceling any

offset generated by or before the In-Gain-stage (Please notice that externally generated offsets, e.g. gen-

erated through the leakage current of the coupling capacitors, are not canceled).

The auto-zeroing is started every time the input source is changed and needs max. 0.3ms for the align-

ment. To avoid audible clicks the Audio processor is muted before the loudness stage during this time.

The AutoZero feature is only present in the main signal-path.

5.2.1 AutoZero-Remain

In some cases, for example if the P is executing a refresh cycle of the IIC-Bus-programming, it is not use-

ful to start a new AutoZero-action because no new source is selected and an undesired mute would ap-

pear at the outputs. For such applications, it can be switched in the AutoZero-Remain-Mode (Bit 6 of the

subaddress-byte). If this bit is set to high, the AutoZero will not be invoked and the old adjustment-value

remains.

5.3

Loudness

There are four parameters programmable in the loudness stage:

5.3.1 Attenuation

-20

-15

-10

-5

0

5

10

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