STA326 datasheet(49/64 Pages) STMICROELECTRONICS

49 / 64 page

DocID11531 Rev 9

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STA326

User programmable processing

8.4

Mix/bass management

The STA326 provides a post EQ mixing block per channel. Each channel has 2 mixing

coefficients, which are each 24-bit signed fractional multipliers, that correspond to the 2

channels of input to the mixing block. These coefficients are accessible via the user

controlled coefficient RAM described below. The mix coefficients are expressed as 24-bit

signed; fractional numbers in the range +1.0 (8388607) to -1.0 (-8388608) are used to

provide three channels of output from two channels of filtered input.

Figure 20. Mix/bass management block diagram

After a mix is achieved, STA326 also provides the capability to implement crossover filters

on all channels corresponding to 2.1 bass management solution. Channels 1 and 2 use a

first-order high-pass filter and channel 3 uses a second-order low-pass filter corresponding

to the setting of the XO bits of I2C register 0x0C. If XO = 000, user specified crossover filters

are used.

By default these coefficients correspond to pass-through. However, the user can write these

coefficients in a similar way as the EQ biquads. When user-defined setting is selected, the

user can only write 2nd order crossover filters. This output is then passed on to the

volume/limiter block.

Obsolete

Product(s)

- Obsolete

Product(s)

STA326 Datasheet(PDF) 49 Page - STMicroelectronics