STV82X7 datasheet(55/156 Pages) STMICROELECTRONICS

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STV82x7

Note:

The unused bits (defined as ‘Reserved’) in the I²C registers must be kept to zero.

The system clock registers (from address 08h to 0Bh and from address 5Ah to 5Dh) do not need to

be modified if a standard 27 MHz quartz crystal oscillator is used.

The default values of the demodulator registers (from address 0Ch to 55h) are for optimum

performances and any change is not recommended, except for:

● AGC_GAIN (0Fh) to adjust AGC gain for AM carrier in L/L' standard (AGC used in open loop).

● CAROFFSET1 (22h) and CAROFFSET2 (3Ah) to compensate IF carrier frequency with an

out-of-standard offset.

● Soundlevel Prescaling PRESCALE_AM (94h), PRESCALE_FM (95h), PRESCALE_NICAM

(96h) and PRESCALE_SCART (97h) to equalize demodulated or external audio signal before

audio processing. Peak detector registers PEAK_DET_INPUT (9Dh), PEAK_DET_L (9Eh),

PEAK_DET_R (9Fh), PEAK_DET_L_R (A0h) can be used to measure internal sound level.

Sound source selection for each audio output channel Loudspeakers, Headphone and SCART to

be done using AUDIO_MATRIX_INPUT (A2h).

In Multi-lingual mode, AUDIO_MATRIX_LANGUAGE (A4h) selects separately the language for

each audio output channel.

can be discriminated automatically. To be used also to change maximum FM deviation (125 kHz, by

default) in case of wide overmodulation. AUTOSTD_STANDARD_DETECT (8Bh) and

AUTOSTD_STEREO_DETECT (8Ch) to define the list of mono and stereo standards to be

recognized automatically.

Note:

() used in reset value column means that the bit or the byte is read-only.

(S) symbol indicates that the field value is represented in signed binary format.

(*) The field AGC_ERR[4:0] (AGC_GAIN) can be written by user if the bit AGC_CMD (AGC_CTRL)

is set to one (by default controlled by Automatic Standard Recognition System). To be used to

adjust manually the input gain of analog AGC amplifier for AM carrier (L/L').

STV82X7 Datasheet(PDF) 55 Page - STMicroelectronics