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7.9.3

Register – AutoMode AM/Pre-Scale/Bass Management Scale (Address 0Ch)

7.9.3.1AutoMode AM Switching Enable

Table 21. AutoMode AM Switching Frequency Selection

ically adjust the output PWM switching rate dependent upon the specific radio frequency that the tuner is

receiving. The values used in AMAM are also dependent upon the sample rate determined by the ADC

used.

7.9.3.2AutoMode Crossover Setting

The XO bits are used to either select one of the 15 preset crossover frequency settings or enable the user

to implement custom crossover filters. The preset crossover settings signify the crossover frequency se-

ferent crossover frequency, other than those available, is desired, then the user needs to set XO = 000

and design custom high-pass and low-pass filters. These filters should then be written to the device coef-

D7

D6

D5

D4

D3

D2

D1

D0

XO3

XO2

XO1

XO0

AMAM2

AMAM1

AMAM0

AMAME

00000000

BIT

R/W

RST

NAME

DESCRIPTION

0

R/W

0

AMAME

AutoMode AM Enable

0 – Switching Frequency Determined by PWMS Setting

1 – Switching Frequency Determined by AMAM Settings

3…1

R/W

000

AMAM (2…0)

AM Switching Frequency Setting

Default: 000

AMAM (2..0)

48kHz/96kHz Input Fs

44.1kHz/88.2kHz Input Fs

000

0.535MHz – 0.720MHz

0.535MHz – 0.670Mhz

001

0.721MHz – 0.900MHz

0.671MHz – 0.800MHz

010

0.901MHz – 1.100MHz

0.801MHz – 1.000MHz

011

1.101MHz – 1.300MHz

1.001MHz – 1.180MHz

100

1.301MHz – 1.480MHz

1.181MHz – 1.340Mhz

101

1.481MHz – 1.600MHz

1.341MHz – 1.500MHz

110

1.601MHz – 1.700MHz

1.501MHz – 1.700MHz

BIT

R/W

RST

NAME

DESCRIPTION

7…4

R/W

0

XO (3…0)

AutoMode Crossover Frequency Selection

000 – User Defined Crossover coefficients are used

Otherwise – Preset coefficients for the crossover setting desired

Table 22. Crossover Frequency Selection

XO (2..0)

Bass Management - Crossover Frequency

0000

User

0001

80 Hz

0010

100 Hz

0011

120 Hz

0100

140 Hz

0101

160 Hz

0110

180 Hz

0111

200 Hz