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STA326

7.5.2

De-Emphasis

By setting this bit to HIGH, or one (1), de-emphasis will implemented on all channels. DSPB (DSP Bypass,

Bit D2, CFA) bit must be set to 0 for De-emphasis to function.

7.5.3

DSP Bypass

Setting the DSPB bit bypasses all the EQ and Mixing functionality of the STA326 Core.

7.5.4

Post-Scale Link

Post-Scale functionality is an attenuation placed after the volume control and directly before the conver-

sion to PWM. Post-Scale can also be used to limit the maximum modulation index and therefore the peak

current. A setting of 1 in the PSL register will result in the use of the value stored in Channel 1 post-scale

for all three internal channels.

7.5.5

Biquad Coefficient Link

For ease of use, all channels can use the biquad coefficients loaded into the Channel 1 Coefficient RAM

space by setting the BQL bit to 1. Therefore, any EQ updates only have to be performed once.

7.5.6

Dynamic Range Compression/Anti-Clipping Bit

Both limiters can be used in one of two ways, anti-clipping or dynamic range compression. When used in

anti-clipping mode the limiter threshold values are constant and dependent on the limiter settings. In dy-

namic range compression mode the limiter threshold values vary with the volume settings allowing a night-

time listening mode that provides a reduction in the dynamic range regardless of the volume level.

7.5.7

Zero-Detect Mute Enable

Setting the ZDE bit enables the zero-detect automatic mute. When ZDE=1, the zero-detect circuit looks

BIT

R/W

RST

NAME

DESCRIPTION

1

R/W

0

DEMP

De-emphasis:

0 – No De-emphasis

1 – De-emphasis

BIT

R/W

RST

NAME

DESCRIPTION

2

R/W

0

DSPB

DSP Bypass Bit:

0 – Normal Operation

1 – Bypass of EQ and Mixing Functionality

BIT

R/W

RST

NAME

DESCRIPTION

3

R/W

0

PSL

Post-Scale Link:

0 – Each Channel uses individual Post-Scale value

1 – Each Channel uses Channel 1 Post-Scale value

BIT

R/W

RST

NAME

DESCRIPTION

4

R/W

0

BQL

Biquad Link:

0 – Each Channel uses coefficient values

1 – Each Channel uses Channel 1 coefficient values

BIT

R/W

RST

NAME

DESCRIPTION

5

R/W

0

DRC

Dynamic Range Compression/Anti-Clipping

0 – Limiters act in Anti-Clipping Mode

1 – Limiters act in Dynamic Range Compression Mode

BIT

R/W

RST

NAME

DESCRIPTION

6

R/W

1

ZDE

Zero-Detect Mute Enable: Setting of 1 enables the automatic zero-

detect mute